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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Simon Clark: The climate lies you'll hear this year

Bob Loblaw at 03:53 AM on 29 April, 2024

nigel:

Reading that quote from Jem Blendell in comment #1, I can't tell if the first paragraph represents an argument against standard climate science, or an argument against the contrarian/denial viewpoint. It's not very well worded. In the second paragraph, it seems more clear that he thinks the contrarian viewpoint is not well supported.

When he talks about "the elites" and people being in the Guardian/BBC/CNN "bubble" and "the whole agenda on climate change", it certainly looks like he accepted some rather bogus arguments against climate science. Personally, don't accept climate science because of what I read in newspapers, web pages, or media outlets - I accept climate science from having learned it in university classes, teaching it in university, and reading the scientific literature and reports summarizing that literature such as the IPCC.

That final sentence in paragraph one finally reassures me that Jem Blendell has not drunk the contrarian koolaid, so the second paragraph is more palatable.

The unfortunate reality is that expecting the general public to become more scientifically-literate is a tough row to hoe. The tier-1 contrarians, who know they are peddling lies, know that emotional and bogus rhetoric wll convince a lot of people. There is the old variant of the old saying:

You can fool some of the people all of the time, and all of the people some of the time...

...and that's enough.

There is also the old Christian Science Monitor cartoon:

Inconvenient Truth

SkS used to have a web page that highlighted contradictions in "contrarian" viewpoints. Things such as "the temperature record is unreliable" while using the same temperature record to claim "no warming since 1998 2016". (The SkS page was taken down because it was too much work to maintain. There is an archived version here.)

The contrarian "science" is full of such contradictions. The ability to believe multiple contradictory viewpoints at the same time is a feature of compartmentalization.

At a glance - Is the CO2 effect saturated?

John Mason at 16:53 PM on 23 April, 2024

re - # 4: I've just taken a look at that paper. The reason we didn't mention it was that it came out very recently.

This however is part of the conclusion:

"However, the intention of the authors of this article is not to encourage anyone to degrade the natural environment. Coal and petroleum are valuable chemical resources, and due to their finite reserves, they should be utilized sparingly to ensure they last for future generations. Furthermore, intensive coal mining directly contributes to environmental degradation (land drainage, landscape alteration, tectonic movements). It should also be considered that frequently used outdated heating systems burning coal and outdated internal combustion engines fueled by petroleum products emit many toxic substances (which have nothing to do with CO2). Therefore, it seems that efforts towards renewable energy sources should be intensified, but unsubstantiated arguments, especially those that hinder economic development, should not be used for this purpose."

In scientific literature, a conclusion should be about the work that was done, and not an arm-waving diatribe! The Introduction likewise gives its first 400 plus words over to arm-wavy waffle about the IPCC. I'm surprised it got beyond peer review on that basis. Indeed, its submission/acceptance dates (Received 4 December 2023, Accepted 11 December 2023) suggests it never was reviewed. In most cases a period of months divides those two dates because the peer review process is quite slow. These are all warning signs that 'something is up' with this item.

Welcome to Skeptical Science

cookclimate at 09:28 AM on 4 April, 2024

CO2 does not cause Earth’s climate change.

It is estimated that it will cost $62 trillion to eliminate fossil fuels, but eliminating fossil fuels will be a complete waste of our tax and corporate dollars, because it will not stop the warming. You can’t stop Mother Nature.

The IPCC (Intergovernmental Panel on Climate Change) frequently shows that temperature correlates with CO2 for the last 1,000 years as proof that CO2 is causing the warming. But if you extend that to the last 800,000 years, the temperature and CO2 lines do not correlate or fit (Figure 14 in Supplemental Data). If the lines don’t fit, then you must acquit CO2. CO2 is not guilty of causing climate change. CO2 does not control Earth’s temperature. The IPCC has not demonstrated any scientific evidence that CO2 controls Earth’s temperature (they only have unproven theories).

The facts:
• Earth is currently warming (it is still below the normal peak temperature).
• CO2 is increasing (it is above the normal CO2 peak).
• Earth’s current warming is being caused by a 1,470-year astronomical cycle.

The 1,470-year astronomical cycle warms the Earth for a couple of hundred years and melts ice sheets primarily in Greenland and the Arctic. It has repeated every 1,470-years for at least the last 50,000 years. It is normal that it would be happening again. It accelerates Earth’s rotation, stopping length of day increases (Figure 9). It warms the Earth. Based on historical data, the current warming should peak near the year 2060 and then it should start to cool.

For more information, see A 1,470-Year Astronomical Cycle and Its Effect on Earth’s Climate,

DOI: 10.33140/JMSRO.06.06.01

and Supplemental Data,
www.researchgate.net/publication/379431497_Supplemental_Data_for_A_1470-Year_Astronomical_Cycle_and_Its_Effect_on_Earth's_Climate#fullTextFileContent

A data scientist’s case for ‘cautious optimism’ about climate change

nigelj at 05:10 AM on 4 April, 2024

William @ 38

"At what point - would you start to not trust a climate alarmist - if deaths continue to fall or not rise for another 40 years - would you think maybe we should not trust those who make these predictions and fuel the narrative. Or do they just get a forever pass - and you will always accept more predictions - even though the people and movements who made them before have always been wrong."

Scientists are making the best predictions and projections they can. The best evidence they have says heatwaves have already become significantly more frequent and intense (refer last IPCC report), and that this situation will get worse over time particularly as warming gets above 2 degrees C. I see no reason to doubt them. The predictions are rational, logical and evidence based. I am a sceptical sort of person but Im not a fool who thinks all predictions should be ignored or that everything is fake or a conspiracy.

Scientists generally predict heatwave mortality will increase and be greater than reducing deaths in winter due to warmer winters, as per the reference I posted @34. What scientists cannot possibly predict is what advances there might be in healthcare and technology that might keep the mortality rate low. All we know is there will likely be further improvements in healthcare and technology, but quantifying them is impossible and it would be foolish to assume there will be massive improvements. We have to follow the precautionary principle that things could be quite bad.

If warming over the next 20 years causes less harm than predicted mitigation policies can be adjusted accordingly. This is far better than just making wild assumptions that global warming would be a fizzer.

Please appreciate that contrary to your comments elsewhere, multiple climate predictions have proven to be correct. Just a few examples:

theconversation.com/20-years-on-climate-change-projections-have-come-true-11245

www.politifact.com/factchecks/2022/oct/25/charlie-kirk/many-climate-predictions-do-come-true

"I think people just want to believe things will be terrible and there are primed believe end of days narratives."

Some people yes. Other people think things will always be fine. Both are delusional views. I would suggest the vast majority of people between those extremes have a more rational, nuanced view and that they look at the overall evidence. Polling by Pew Research does show the majority of people globally accept humans are warming the climate and we need to mitigate the problem.

"Yes - anything could happen in the future and deaths and damage levels could rise again- but it is nor healthy to ignore the present - or trust people that wilfully distort it."

I'm not ignoring the present or past. The mortality rate from disasters has mostly fallen over the last 100 years and that looks like robust data. I didn't dispute this above. I dont recal anyone disputing it. However you cant assume that trend will always be the case. The climate projections show deadly heatwaves are very likely to become very frequent and over widespread areas, and so obviously there is a significant risk the mortality rate will go up.

It's almost completely certain that at the very least considerably increased resources will have to go into healthcare, air conditioning, adaptation, etc,etc. This means fewer resources available for other things we want to achieve in life. Once again its not all about the mortality rate per se. So when I look at the big picture there is a strong case to stop greenhouse gas emissions and transition to a new zero carbon energy grid.

Climate - the Movie: a hot mess of (c)old myths!

scaddenp at 06:38 AM on 3 April, 2024

Two dog. The OHC content data in red comes from the Argo array. You can find reasonable description here. The old pentadecadal data is ship-based and has much bigger error bars. I cant immediately find the paper that determined the accuracy of the Argo data but if interested I am sure I dig it out.

On interannual and to some extent the decadal scales, variations in surface temperature are strongly influenced by ocean-atmosphere heat exchange, but I think you would agree that the increasing OHC rules that out as cause of global warming?

"I did also read that the warming effect of CO2 decreases as its concentration increases so the warming is expected to reduce over time. Is there any truth in that?"

Sort of - there is a square law. If radiation increase from 200-400 is say 4W/m2, then you have to increase from CO2 from 400 to 800ppm to get 8W/m2. However, that doesnt translate directly into "warming" because of feedbacks. Water vapour is powerful greenhouse gas and its concentration in the atmosphere is directly related to temperature. Also as temperature rises, albedo from ice decreases so less radiation is reflected back. Worse, over century level scales, all that ocean heat reduces the ability of the ocean to absorb CO2. From memory, half of emissions are currently being absorbed there. Hot enough and the oceans de-gas. These are the calculation which have to go into those climate models.

Which brings us to natural sources. Geothermal heat and waste heat are insignificant so would you agree that the only natural source of that extra heat would be the sun? Now impact of sun on temperature has multiple components that climate models take into account. These are:
1/ variations in energy emitted from the sun.
2/ screening by aerosols (natural or manmade). Important in 20th century variations you see.
3/ changes in albedo (especially ice and high cloud)
4/ The concentration of greenhouse gases in the atmosphere.

Now climate scientist would say that changes to all of those can account for all past natural climate change using known physics. They would also say very high confidence that 1/ to 3/ are not a significant part of current climate change (you can see the exact amount for each calculated in the IPCC report). Why are they confident? If you were climate scientist investigating those factors, what would you want to measure to investigate there effects? Seriously, think about that and how you might do such investigations.

Is it possible there is something we dont understand at play? Of course, but there is no evidence for other factors. You can explain past and present climate change with known figures so trying to invoke the unknown seems to be clutching at straws.

A data scientist’s case for ‘cautious optimism’ about climate change

Bob Loblaw at 04:41 AM on 3 April, 2024

William @ 30:

No, I do not agree that deaths are "the most important" thing. And I do not agree that past trends in deaths present evidence that there will not be many deaths in the future. If I had to be on future causes of deaths related to climate change, I'd put it on massive failures of agriculture (which we are already seeing the early signs of), massive migrations of people fleeing lands that can no longer support them (they are not going to just roll over and die - they'll be showing up in your back yard), and massive instability in our economies and society as people try to adapt to the new conditions.

...and before people start dying, there can be an awful lot of pain and suffering.

As for your questions about:

with disasters not increasing

You again equate disasters with death. There is lots of evidence that disaster costs are increasing.

deaths at an all-time low

You base this conclusion on a single newspaper report.

and fewer people dying from direct weather deaths and crop yields at their current improved rate.

Agriculture is already being affected negatively. And it will get worse.

Your idea that the IPCC doesn't think we have a problem is so far from what they say. (Unless, of course, your only metric is deaths so far.)

A data scientist’s case for ‘cautious optimism’ about climate change

michael sweet at 23:01 PM on 2 April, 2024

William,

Once you build the wind and solar generators you don't have to buy fuel to run them every day so they are cheaper than fossil fuels. You continue to only measure the cost of the renewable side. Who cares if it costs L1.4 trl to build out renewables if the cost of fuel is L3 trl? The article I linked included storage for enough power so that there would be no shortages, you just didn't read it. Fossil or nuclear backup are not necessary.

I remember 10 years ago the IPCC report suggested that Global Warming would eventually cause sea level rise that endangered houses near the sea, wildfires and droughts that caused massive relocations of people. I wondered if I would see these damages in my lifetime. I expected to live about 25 years.

We see all these things happening now, only 10 years later. They are no longer future projections. Wildfires are destroying entire towns and massive amounts of forrest. Unprecedented droughts and floods are making it harder for farmers to turn a profit. Millions of climate refugees are already trying to access the Global North because they can no longer make a living due to climate change. The damages we currently see are much, much higher than scientists projected only 10 years ago. 40 years ago they thought the great ice sheets would take thousands of years to melt as much as they have already melted now. No-one thought that all the coral reefs worldwide would be dying off as we see today.

We do not need to wait 40 years to see these problems. You are blind to what is happening before your eyes.

Climate - the Movie: a hot mess of (c)old myths!

Bob Loblaw at 05:50 AM on 29 March, 2024

Two Dog @ 32:

You seem to be under the impression that nobody has tried to explain the observed temperatures using anything other than CO2. This is patently false.

This SkS rebuttal looks at conclusions drawn by the IPCC in 2007, looking at a variety of possible explanations. The first figure from that post shows contributions to radiative forcing from several sources:

IPCC 2007 SPM figure 2

...and the second figure on that post shows modelling of temperatures over the last century with and without anthropogenic forcing:

IPCC 2007 SPM fig 4

So when you try to answer Eclectic's question, you'll need to come up with something that is not on that list.

If climate scientists have been "shutting down the debate", it's because they have looked at the proposed alternatives and found that the evidence is against them.

Climate - the Movie: a hot mess of (c)old myths!

One Planet Only Forever at 02:59 AM on 28 March, 2024

Two Dog @26,

The movie in question is still questionable and misleading even if it contains 'points that have merit'.

I am a structural engineer with an MBA. I present two examples for the merit of my opening point:

A structure design is unacceptable even if some parts of the design could be claimed to be 'perfect'. All it takes is one obvious error to justifiably declare the design to be unacceptable.

A business plan is unacceptable even if some parts of the plan could be claimed to be 'perfect'. All it takes is one obvious error to justifiably declare the plan to be unacceptable.

As for the ‘merit’ of things in the questionable misleading movie you perceive to have merit:

Climate Change can be understood to be the term applied to the vast body of science that has proven conclusively that human impacts, not just CO2 from fossil fuel use, have caused significant rapid changes to the climate conditions of regions on this planet. “Climate Change Denial” is a term referring to people who resist learning about the constantly improving understanding of Climate Change science.

The answer provided above questions the merit of your second ‘perceived point of merit’ about the significance of human impacts. There are many presentations of better understanding that shatter the ‘merit of what you perceive is a point of merit’. One example is SkS Myth/Argument 192 “The IPCC confidence in human-caused global warming is based on solid scientific research”. A related presentation is the Carbon Brief item form 2017 “Analysis: Why scientists think 100% of global warming is due to humans” (and more recent investigations have strengthened that understanding).

I will conclude with the following: “Resistance to learning”, not “shutting down debate”, is the real problem. Being ‘hard-of-learning’ (see my comment @18), can cause people to claim that justifiably criticizing their ‘questionable attempts to debate points they unjustifiably believe have merit’, and pointing out that ‘repetition of already well-debunked misunderstandings has no merit’, is “shutting down debate”.

Note: Regarding ‘covid’ you did not present an example of a ‘conspiracy theory’ you believe was proven to be correct. But I would suggest that for this topic on this website you should focus on presenting an example of what you believe is a ‘climate change conspiracy theory’ that has proven to be correct. One example I am aware of is the ‘conspiracy theory’ that undeserving wealthy powerful people have been deliberately misleading regarding Climate Change science resulting is massive amounts of unjustified “Climate Change Denial”.

Is Nuclear Energy the Answer?

michael sweet at 00:24 AM on 24 February, 2024

John ONeill:

You link to a Nuclear Energy Agency report, hardly an unbiased source, that contains no data or analysis. They link to an IPCC report where the summary for policy makers alone is 24 pages long. The report is hundreds of pages. You must provide a link to an evidence based report and give me the pages that relate to the topic we are discussing. Most proposed future energy systems have a little nuclear since plants currently under construction will presumably still be running in 26 years.

Your other link, which I have previously debunked upthread, is a web piece by a completely uninformed person who has no education or experience in nuclear energy and learned everyting they know about nuclear from the internet. (If you read the rest of this thread you would stop repeating the mistakes nuclear supporters have made upthread). He models the current electrical supply in the USA. Since all cars and all heating by heat pumps will be electrical it is expected that electrical consumption in the USA will at least double. His system is much too small. He uses fossil gas for storage since the required storage would be too expensive to build. I note that a system using fossil gas for storage does not stop emitting CO₂ as required. Duh! The cost is prohibitive, he assesses cost incorrectly. The ignorant errors in this analysis are too numerous to address. The fact that nuclear supporters cite this blog proves that nuclear is not economic.

Do you really want to run Afganistan and Yemen completely on nuclear? A solution that does not work for most of the world is hardly a reasonable proposal. There is only enough uranium in all known deposits to run the entire world for 5 years. (Abbott 2012). Read Abott 2012 (linked in the op).

Here is free link to the Jacobson et al 2022 paper titled "Low-cost solutions to global warming,air pollution, and energy insecurity for145 countries". Note that Jacobson describes a solution suitable for the entire world and not just the USA. Upthread I have provided at least a dozen links to free papers that describe completely renewable systems to generate all energy for the entire world. If you read Jacobson you will have more knowledge of what we are talking about. You currently are not very informed.

Here is a free link to a paper titled "On the History and Future of 100% Renewable Energy Systems Research", one of the 59 papers that have cited the Jacobson paper. If you read it you will be more informed about what energy researchers think about future energy systems and make fewer ignorant statements online.

If you have not put in the work to learn how to find papers that support your position it is not my problem. It is not my job to spoon feed you information that you cannot be bothered to read yourself. You have to do your homework if you want to tell other people what they should do. Uninformed proposals do not help advance the discussion.

The fact that you cannot find anything to support your position demonstrates that the nuclear discussion on line is completely fantasy based and not fact based. If documents supporting the nuclear position existed than nuclear supporters would cite them. Nuclear supporters cite industry propaganda as if it were fact based information.

Whenever I examine nuclear supporters claims closely I find that they are not supported by the data.

Nuclear is not economic, takes too long to build and there is not enough uranium.

Is Nuclear Energy the Answer?

John ONeill at 19:26 PM on 23 February, 2024

'Please provide one example of a peer reviewed proposed future world power system that uses more nuclear than the currently built reactors.'

'The IPCC found that, on average, the pathways for the 1.5°C scenario require nuclear energy to reach 1 160 gigawatts of electricity by 2050, up from 394 gigawatts in 2020. 1 160 GW by 2050 is an ambitious target for nuclear energy, but it is not beyond reach.' https://www.oecd-nea.org/upload/docs/application/pdf/2021-10/nuclear_energy_and_climate_change_-_cop26_flyer.pdf

Insisting on peer reviewed papers is a good way of ensuring that I can't read them. Here's a calculation on the cost of moving the United States to 100% nuclear electricity. As Joris van Dorp writes, it's a thought experiment on the cost of providing percentages of nuclear from 0 to 100, at various interest rates and build costs. '..It looks like solar and wind are today cheap enough to allow them to work economically as a fuel saving technology with natural gas. And if nuclear costs stay as high as they are today, it even looks as though a combination of storage, wind, solar, demand response and nuclear may be an optimal mix for a zero carbon energy system. However, this does not detract from the fact that nuclear power as a single technological concept is evidently sufficient to allow achieving a low-cost zero-carbon energy system, with no help needed at all from any wind power, solar power or anything else, which is the only thing this article was intended for.'

https://medium.com/generation-atomic/how-much-would-a-100-nuclear-energy-system-cost-3dd7703dd5d3

Increasing CO2 has little to no effect

Dominic68 at 00:09 AM on 3 February, 2024

I have had this publication and this one cited against me in argument. Has anyone come across them? Essentially they are being used to argue that C02 > 400ppm concentration will not trigger further heating.

It's only a few degrees

retiredguy at 23:02 PM on 18 January, 2024

I'm reading climate skeptic/deniers claim that because winter, nightime and high latitude temps have increased more than summer, daytime and lower latitudes, that the negative impacts of global warming are being exaggerated by climate 'alarmists', and that furthermore, the IPCC and climate scientists are intentionally not highlighting this. Can you comment ?

At a glance - Is the CO2 effect saturated?

nigelj at 06:49 AM on 11 January, 2024

The sceptics claim that the CO2 warming effect is already saturated or is close to being saturated is clearly false. It seems to originate with the assertion that the surface receives about 3.7 W/m2 more energy each time CO2 is doubled ie: a logarthmic curve. This means eventually it would take a huge volume of additional CO2 (presumably over a long time period) to add an extra 3.7W / m2. Which they suggest means the effect is essentially then saturated, but without specifying a precise number (how convenient of them).

I see that the article mentions that this assertion about a logarithmic relationship may have been proven false by He et al. 2023, (?) and it also depends on emissions trajectories and other factors, but assuming the logarithmic relationship is simplistically true a look at radiative forcing versus CO2 concentration below and a bit of maths and its obvious the warming effect is not saturated and we are not yet near saturation:

skepticalscience.com/why-global-warming-can-accelerate.html

My back of envelope maths: In 1960s CO2 was 320 ppm ppm so doubling would be 640 ppm at around roughly year 2100 assuming BAU emissions. This coincides with the IPCC warming projection of 3 - 5 degrees C by 2100.

The next doubling is from from 640 to 1280 is a larger volume of CO2 and would presumably take longer to around year 2300 assuming the same BAU CO2 growth trend and other things being equal. Projections of warming by the IPCC by 2300 are not surprisingly around 8 - 10 degress C for this further doubling of CO2. Such a quantity of CO2 is large but may possibly be feasible given reserves of fossil fuels and uncertainties arount that.

The next doubling from 1280 to 2560 would lead to something like 15 degrees C and is a huge volume of CO2 that would take many centuries and would almost certainly exhaust reserves of fossil fuels, and most probably well before 15 degrees is reached. We could say this is the point of saturation in a practical sense. Its of no comfort because we would have had at least 5 degrees of warming and probably more, and not even factoring in tipping points.

Someone check my maths its very rough, but the sceptics claims are clearly false and meaningless.

Scientific Consensus with Dr John Cook

Evan at 02:08 AM on 10 January, 2024

Ben@1 and nigelj@2, I tend to agree with both of you, but would defer to someone with deeper knowledge of the IPCC than I have.

My understanding is that Ben is correct in terms of historical IPCC predictions, but that Nigel is correct in terms of the latest report, which now does include more extreme predictions than previously included.

But the other message that I keep hearing in videos and reading in text is that the climate is responding/changing faster than many climate scientists expected, and by my reading, this sentiment is not refleccted in the IPCC reports.

Scientific Consensus with Dr John Cook

nigelj at 05:04 AM on 9 January, 2024

Ben Laycock @1

I disagree that the IPCC only include the most conservative estimates of warming and SLR. Firstly the most conservative estimates for warming are roughly 3.0 degrees C by 2100 at BAU (business as usual emissions) and on SLR are roughly 0.6 M this century. The IPCC sixth assesssment report also includes warming projections of up to 5 degrees C and and SLR projections of 1 - 2 metres this century ( which look very possible to me). So clearly the IPCC does not include only the "most conservative" estimates.

You can google the IPCC reports. They are free to download.

A small number of scientists like James Hansen have written studies with higher estimates of warming and SLR but they are not included as the IPCC presumably decided the science was not quite convincing enough. The IPCCs job is to review all the science and decide which is most credible. That also includes reviewing studies claiming the planet is about to enter a long cooling period. They dont include those because they lack any credibility.

However IMO the Summary for Policymakers could do a better job of highlighting the worst case scenarios and their implications.

Its true the IPCC do lean a little bit conservative on the science generally. However this is how science has worked for decades and its to help avoid mistakes and loss of credibility. It may be frustrating at times but the alternative sounds worse to me. Policy makers also presumably realise there is a certain conservative leaning or reticence and take that into account.

And remember there is nothing reassuring about SLR projections of up to 2 metres this century. This is obviously very serious and if anyone can't figure that out I doubt that a higher estimate of 3 metres would make much difference to them.

I agree that we have to be cautious interpreting the meaning of low possibility high impact events like 5 degrees warming this century or 2.0M SLR. Firstly as you say they can still happen. Secondly they are assigned a low possibility of occurence but that is probably a "conservative" leaning evaluation or probability. Thirdly the impacts are so incredibly serious that even although the possibility is low we need extreme caution and should therefore be mitigating the climate problem. There are many activities that have a low possibility of harm but very serious outcomes, that sensible people avoid like driving on worn tires that are just slightly below warrent of fitness standards.

Scientific Consensus with Dr John Cook

Ben Laycock at 07:12 AM on 7 January, 2024

Whilst it is reasurring that the information in the IPCC reports is reached ia consensus, it can gie us a false sense of security because only the most conservative estimates are included. The most alarming possibilities are left out because they are deemed unlikely. So the possibility of global temperatures reaching an insufferable 4 degrees higher is not something we should be concerned about because it is not very likely to happen.... until it does!

A New 66 Million-Year History of Carbon Dioxide Offers Little Comfort for Today

One Planet Only Forever at 04:12 AM on 14 December, 2023

MA Roger,

Thank you for pointing to alternative approaches to global warming scenario development. And thank you for pointing out those justified concerns about how the limited scope and method of presentation of an evaluation can be misleading.

In all honesty, I conceptually created the 3 situations to try to make the point that how we get to a global warming impact temperature value at 2100 and what is done after 2100 makes a difference. I hoped to present the understanding that there are a variety of ways of achieving a value of 2100 warming impact, with an ‘important differentiating consideration’ being what happens beyond 2100. And I simply chose to call the three created example situations ‘scenarios’.

I chose 1.7 C in an attempt to be brief but clear that I am not referring to any of the formally presented scenarios. I am pessimistic that the 2100 warming impact level of SSP1-1.9 is likely to be achieved. But I am hopeful that something better than SSP1-2.9 can be achieved. The important point is that there are many ways to conceptualize getting to the same 2100 impact result. And the variety of ways of getting that 2100 result, including what happens after 2100, are not ‘equivalent levels of harm reduction’.

I will add that my MBA included Organizational Behaviour and Design where I learned that it is incorrect to believe that a specific set of policy or operational rule changes can be certain to produce a desired ‘objective change’ (I believe this is part of the reason for the range of results for each IPCC scenario). New policies and rules may result in changes, or they may not, or they produce unanticipated changes.

When there is a need to change the collective behaviour of the members of any organization, including the organization of all of global humanity, a diversity of hoped to be helpful policy and rule changes can be conceptualized. And some of those changes would be based on improved understanding developed in the very hard to investigate fields of social, political, and economic behaviours where irrational behaviours can, and do, significantly occur. Irrational behaviour, including resistance to learning to be less harmful and more helpful to others, can especially occur due to the potential to benefit unjustifiably, especially from from secrecy (people less aware than they could be) or the popularity of misunderstanding (abusing the powerful science of marketing).

Therefore, when pursuing an objective correction of unsustainable or harmful developed behaviours by changes of policy or rules it is important to diligently monitor the changes that actually occur and revise the policy and rule changes as required to increase the chances of achieving the desired correction of collective behaviours. (hopefully accomplished by each COP session).

I have to add that when I got my MBA education in the 1980s it was rather rare to have the MBA program include ‘social and psychological’ considerations. Most MBA programs of the time, particularly the most prestigious programs, were focused exclusively on ‘maximizing making money matters most’, like Economics, Accounting, Finance, Efficiency of Operations and Material supply, Marketing, and Legalities related to financial activities and contracts.

A New 66 Million-Year History of Carbon Dioxide Offers Little Comfort for Today

MA Rodger at 19:46 PM on 13 December, 2023

One Planet Only Forever @3,

Where do you source your "set of scenarios with equal 2100 temperature values of 1.7 C" ?

I do note the use of IAMs to create scenarios & MAGICC to calculate the climatic outcomes does provide a route to developing such scenarios with a lot less effort than the SSP -> GCM approach. And I also note the rather worrying way such scenarios are presented simply as % cuts by 2050 along with a temperature rise. This is worrying as the cuts required over shorter and longer timescales are airbrushed away, this often along with the substitution of CO2 emissions timings for CO2(equivalent) emissions which can be very significant (as per AR6 WGIII Fig3.6 below). IPCC AR6 WGIII FIG3.6

A New 66 Million-Year History of Carbon Dioxide Offers Little Comfort for Today

nigelj at 05:38 AM on 13 December, 2023

The information on earth system sensitivity of 5 - 8 degrees C is very sobering. There are many accounts of what a 6 degree world is like easily googled and its very inhospitable for humans and other species. Because ESS develops on long time frames we might adapt to some extent, but that doesn't really make it any less inhospitable.

This is one authors depiction of a 6 degree world based on available research. The description is based on such a world developing over the next couple of centuries and a failure to curb emissions, but even if it takes thousands of years as a result of ESS, many of the outcomes would be similar.

"Special coverage is given to the positive feedback mechanisms that could dramatically accelerate climate change. The book explains how the release of methane hydrate and the release of methane from melting permafrost could unleash a major extinction event. Carbon cycle feedbacks, the demise of coral, the destruction of the Amazon rainforest, and extreme desertification are also described, with five or six degrees of warming potentially leading to the complete uninhabitability of the tropics and subtropics, as well as extreme water and food shortages, possibly leading to mass migration of billions of people."

LINK

The IPCC seems to have focused most attention on warming and sea level rise rates by 2100. We have projections of around 3 degrees C of warming and worst case about 5 degrees, and SLR around 1 metre with a worst case 2 metres. The details on longer term trends several centuries into the future, or millenia into the future like earth system sensitivity, are buried away in their reports or not given much attention.

The IPCC have a chart buried in their reports showing a worst case of about 10 degrees C by about 2300 if equilibrium climate sensitivity turns out to be high and we just go on burning fossil fuels. Likewise by 2300 SLR could be well over 2 metres. This may be somewhat attenuated by the impacts of renewable energy already reducing projected coal use, but it would still be a big number and theres a lot of SLR already baked in even if we stop warming right now.

I wonder if this focus on year 2100 is a deliberate psychological strategy to focus on our immediate future. If they focused on the longer term trends there might be a risk that people would say why worry that won't effect me or my children.

However warming of for example 3 degrees by 2100 and one metre or so of SLR doesnt sound very scary to some people, while numbers like 5- 8 degrees longer term and SLR of 10 - 20 metres are obviously intuitively far more scary and certainly get my attention. Clearly we do need a focus on year 2100, for obvious reasons, because its in our lifetimes and adaptation would be very costly, but I wonder if a bit more attention on longer term time frames would have really shown people the huge scale of change we are facing.

Skeptical Science New Research for Week #49 2023

nigelj at 04:35 AM on 10 December, 2023

MS Sweet. Good information to know.

"I note that Dr. Hansen has long held an Earth System Sensitivity of 6 C. The IPCC consensus has been 3C"

The IPCC number is "equilibrium climate sensitivity", a different thing from earth system sensativity as below. Making it hard to compare the two numbers.

"By definition, equilibrium climate sensitivity does not include feedbacks that take millennia to emerge, such as long-term changes in Earth's albedo because of changes in ice sheets and vegetation. It includes the slow response of the deep oceans' warming, which also takes millennia, and so ECS fails to reflect the actual future warming that would occur if CO2 is stabilized at double pre-industrial values.[38] Earth system sensitivity (ESS) incorporates the effects of these slower feedback loops, such as the change in Earth's albedo from the melting of large continental ice sheets, which covered much of the Northern Hemisphere during the Last Glacial Maximum and still cover Greenland and Antarctica)...."

(Climate sensitivity, wikipedia)

We will probably never know any of these numbers for sure because you can't put the planet in the laboratory. (Although I think paleo studies like the one you posted have a lot of credibility - because they are based on real world conditions). But IMHO that uncertainty is not necessarily a crucial problem. Current rates of warming are bad and are having very visible effects, and huge implicatrion in the short to medium term, and so whatever the level of climate sensitivity using whatever definition, we clearly have a huge problem.

Skeptical Science New Research for Week #49 2023

michael sweet at 01:16 AM on 10 December, 2023

This MSN article, Which is apparently a press release from the Columbia Climate school describes a paper in Science. The paper is a collaboration of many scientists summarizing knowledge of CO2 concentrations for the past 65 million years. The MSN article is easy to read. Since it is a press release it would be a good OP here at SkS. I have not yet read the paper.

Unfortunately, they conclude that Earth system sensitivity, the climate response when all slow feedbacks respond, is 5-8 C. The processes involved can take a long time to equilibrate (as much as thousands of years). Still, it is a very grim conclusion. I note that Dr. Hansen has long held an Earth System Sensitivity of 6 C. The IPCC consensus has been 3C. This is unlikely to affect anyone living but bodes very bad for 1000 years from now. The question of how long the slow processes take to equilibrate is left unanswered.

At a glance - Evidence for global warming

Paul Pukite at 07:31 AM on 7 December, 2023

You may be skeptical of the claims, but they're out there and after 5 years no-one has tried to refute, debunk, or falsify the claims. I submitted a presentation to next spring's US CliVar Workshop which they're calling "Confronting Earth System Model Trends with Observations: The Good, the Bad, and the Ugly".

Comparing historical trends in Earth system models with observations to identify and understand where models are performing well and poorly to focus the community on where more work is needed to ensure credible projections moving forward. What are we getting right? What are we getting wrong and why? What have we not yet paid enough attention to and where might surprises lie?

Objectives
For over 40 years, and through several rounds of IPCC reports, the climate science community has made projections of climate change under specific emissions scenarios. While assessments of the fidelity of Earth System Model simulations over the historical period have been performed for basic variables such as near surface air temperature, internal variability and a relatively small signal in a short observational record has made a comprehensive assessment challenging.

My submitted abstract addresses the internal variability part. I don't know yet whether it was accepted for presentation, but I'm confident that it won't be wasting anyone's time.

John F. Clauser: the latest climate science-denying physicist

John Mason at 22:34 PM on 29 November, 2023

Re #63: " I believe it's also true that in the last ice age the level of atmospheric CO2 was at least 10 times current levels - which according to IPCC thinking ought to have produced a blisteringly hot climate - yet there was an ice age. "

You believe incorrectly unless by "last ice age" you are referring to something hundreds of millions of years ago.

During the last glacial maximum of the Quaternary, ca. 23,000 years ago, CO2 was around 180 ppm.

John F. Clauser: the latest climate science-denying physicist

AB19 at 21:32 PM on 29 November, 2023

I quote from the article introduction:

"It’s a familiar story – the physicist who draws attention for declaring that climate scientists have got climate science all wrong. He (it’s always a ‘he’) was born before color television was invented, usually retired, perhaps having won a Nobel Prize, but with zero climate science research or expertise. William Happer."

I don't know if the writer of the article is a scientist or not but it starts with some rather unscientific viewpoints, namely by suggesting that male, retired physicists are not qualified to comment on climate matters. What does it matter what sex they are or how old they are? In relation to physicists, I don't know about the others in the list given, but William Happer would, I would have thought, certainly qualify to comment on the global warming debate given that if you have watched any of his presentations on this topic, you'll know that his field of research was the absorption of infra-red radiation by CO2 molecular stretches and bends - very apt in the climate debate I would have thought, given that it is precisely CO2 that is being posited as the culprit in current global warming trends. He also openly admits that he was once a climate alarmist until his work led him to believe he was wrong.
I am not a climate scientist- my background is chemistry- but there are certain apparent facts that appear to be ignored in the current debate, namely that we know the earth warmed before about 1000 years ago in the medieval warming period and again about 2000 years ago in the Roman period. These warmings cannot have been due to human activity given that there were no combustion engines or factories around and world population was vastly lower than today. I believe it's also true that in the last ice age the level of atmospheric CO2 was at least 10 times current levels - which according to IPCC thinking ought to have produced a blisteringly hot climate - yet there was an ice age. Whilst not denying that CO2 is x greenhouse gas, these facts do tend to cast doubt on just how potent a greenhouse gas CO2 really is. I believe Dr Roy Spencer, who is a meteorologist not a physicist and also not retired ( though he is male) has similar views to the listed physicists.

Disinformation campaigns are undermining democracy. Here’s how we can fight back

Nick Palmer at 12:23 PM on 26 November, 2023

What NigelJ said is very valid. My own perspective on such matters as percption of climate science is that probably most 'sides' - from doomist through alarmist to 'IPCC' accepting to 'sceptic' to denier - now currently distort the science and the varied consequences of assorted policies to suit their favoured take - often very strongly influenced by their personal politics. All sides use the very same techniques of cherry picking, quote mining, over-promoted 'experts', out-dated articles etc to make their cases. The actual peer reviewed science tends to get lost in the noise

Can we still avoid 1.5 degrees C of global warming?

Bob Loblaw at 04:50 AM on 15 November, 2023

kar @ 2:

Your answer to the question about pre-1990 data is not hard to find. The authors of the blog post kindly added a link to the image source in the caption.

If you follow that link, you can download the report. If you go to the original version of the figure in the report, it says:

Sources: Upper panel: Historical data from the IPCC for 1950–1989 and from the 2022 NDC synthesis report for 1990–2020; 2030 projections from NDCs; and the reduction scenarios from the AR6 Synthesis Report

I have no idea what you are trying to imply by the term "stipulated".

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

MA Rodger at 21:23 PM on 8 November, 2023

This Hansen et al (2023) paper was pre-published back in January and did result in a bit of discussion here at SkS. And there was supposed to be a second paper specifically on SLR.

Hansen et al rattle through a pile of stuff, some of which I would agree has merit and some which I find difficult to accept, some very difficult. The high ECS is one of the very difficult ones. (Perhaps the point that the big part of the difference between high ECS values and the IPCC's most likely value ECS=3ºC, [something the IPCC tend not to identify preferring a range of values as in AR6 Fig1.16]: the difference is due to warming that follows the forcing by a century or more. That time-lag is one of the reasons the ECS estimates are not better nailed down and still has its 'fat tail' . It also would give mankind a fighting chance of dodging it.)

SLR is certainly a big subject of concern. It is a long-term problem, multi-century. The equilibrium position for a +1.5ºC is perhaps 3m and the threat of setting Greenland into unstoppable meltdown at higher levels of warming would triple that. I do tend to get irked by the SLR by 2100 being the sole subject of discussion.

Of course, predictions of that 2100 SLR being massive (5m) is one of Hansen's foibles. The worry is, I think, specific to Antarctica and it is a genuine worry. But to achieve 5m by 2100 would need massive numbers of icebergs bobbing around in the southern oceans and result in global cooling. And there is also the awkward point for climatologists that increased snowfall over Greenland/Antarctica could provide a significant reversal of SLR.

The final issue raised by Hansen et al (2023) is the impact of the reduction of aerosols from our falling SO2 emissions. Quantifying the impact of SO2 emissions is not entirely global a thing, so emissions in, say, China may induce more cooling than, say, Europe. But that said, global SO2 emissions data I identify tends to be way out-of-date. The most recent is this one from a Green Peace publication. This shows the reduction in SO2 is well in hand over the last decade. And the CERES data showing EEI does show a drop in albedo (yellow trace in the 2nd graphic) through that period. My own view of these CERES numbers is that they include a lot of bog-standard AGW-feedback-at-work.

SO2 emissions 2005-19

CERES TOA fluxes

There is also the last 5 months of crazy global temperatures (so post-dating Hansen et al's pre-publication). I don't see these as being sign of things to come. I'd suggest it is casued by the January 2022 Hunga Tonga eruption which threw both SO2 and H2O into the stratosphere, the cooling SO2 dropping out leaving the warming H2O to do its thing before eventually it too dropping out.

And the in-the-pipeline thing. Climatology is/has-been saying we need to halve CO2 emissions b 2030, and following the point of net zero in mid century we enter a century-plus of net-negative CO2 emissions. That would see all emissions 2008 to year-of-net-zero removed by human hand and stored away safely. So that is on top of the natural draw-down of CO2 into the oceans. And if we don't do that, it will not be from ignorance of the situation.

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

michael sweet at 02:39 AM on 8 November, 2023

I don't think Hansen is worried about thousands of years in the future. He has been saying for decades that aerosols are reflecting a lot of energy back into space, cooling the planet. Reducing fossil fuel use reduces aerosols. The loss of aerosols causes rapid warming. Hansen projects that 1.5C will be exceeded by 2030 and 2.0 C will be exceeded by 2050. He is concerned about changes that will occur while people alive now are still around, about 100 years. He is concerned about multimeter sea level rise by 2100. If Hansen is correct about aerosols the next 30 years will have substantial extra heating.

I respect Zeke and Mann but their explainations for the extreme heat the past 6 months are pretty weak. While the current temperatures are inside the error bars for the models, the temperature this year is extraordianrily hot comnpared to all previous years. I note that the IPCC generally emphasizes what a consensus of scientists think is the minimum amount of change in the climate and temperature. That means that a majority of scientists think it will be worse than the IPCC projections.

The scientists who project damages substantially exceeding the IPCC reports are in the minority. It is very concerning to me that they exist at all. Especially since the last 6 months have been so hot and next year is projected to be even hotter. El Nino does not usually strongly affect temperature until the end of the year.

I agree that "it's important to communicate the incredible challenges we face but without instilling in people's minds the idea it's already a lost cause." But politicians still are not taking action seriously.

What is the IPCC defination of "consensus". It has to be a lot higher than 50%. Is it 80%, 90%? They must have it written down somewhere.

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

Evan at 23:59 PM on 6 November, 2023

Dean@4, When the IPCC was just being formed, it was Hansen in 1988 who was sounding the alarm. Hansen has always been at the forefront of climate predictions, preceding the IPCC in his assessment of how severe the climate crisis is and will likely become. The IPCC has always represented a baseline assessment of where we're heading, and not necessrily an accurate assessment of just how bad things could get.

But let's find common agreement, because I've read the paper by Hausfather (read here) where he shows that temperatures will be frozen if we reach Net 0 emissions. I understand the arguments you're making.; But with CO2 concentrations rising at 2.5 ppm/year, and the state of world affairs leaning ever more to the right, it will be a long long time before I hold any hope for reaching Net 0 emissions. I will continue to encourage others to view our warming commitment as corresponding to the current level of CO2 in the atmosphere. Anything beyond that is contingent on global actions that are still struggling in their infancy. Yes, we have lots of talk and agreements, yes wind power has been increasing, but with CO2 rising at 2.5 ppm/year, apparently we have yet to sufficiently impress the natural world that we're doing enough.

2023 SkS Weekly Climate Change & Global Warming News Roundup #44

Just Dean at 23:31 PM on 6 November, 2023

Evan, It is not just Mann that disagrees with Hansen. I believe that Hansen holds the minority position here. Both Zeke and Mann reference the IPCC special report on 1.5C that warming will cease when we get to net zero emissions. To me, the IPCC represents the consensus thinking. There is a recent paper by Dvorak and Armour that reaches bascially the same conclusion, Ref. , and adresses the aerosol effect.

If you follow Zeke at theclimatebrink.com and/or X, he has addressed directly Hansen's pipeline paper and his high estimate of climate sensitivity. Also, Zeke's latest analysis of record breaking temperatures relative to the multimodel averages can be found at theclimatebrink.com.

2023 SkS Weekly Climate Change & Global Warming News Roundup #42

One Planet Only Forever at 08:57 AM on 26 October, 2023

Wilddouglascounty @4,

Someone may be able to "... highlight a list of educational resources, incentives, and campaigns that put these recommendations front and center ..."

But, I will start my response with a minor, but important, clarification of your opening comment (edits in bold) “... and then some news media is beginning to focus on how devious the fossil fuel investors are in using misinformation, disinformation, and obfuscation along the lines of the tobacco mercenaries while some media players, especially the ‘social type’, continue to be part of the misinformation and disinformation efforts.”

As for the questions asked ... the answers involve the need for increased critical thinking in pursuit of increased awareness and improved understanding of how to be less harmful and more helpful to others and seeking understanding of the bias of any information source (note that SkS is an excellent resource for that).

Having a bias towards helpful well-reasoned understanding of ‘all of the relevant evidence’ will produce results that differ from other sources. Such presentations can still be ‘claimed to be biased’. But ‘evidence of bias’ does not make a source ‘unreliable and unhelpful’. It is undeniably more damaging to be biased against more fully informing how to be less harmful and more helpful to others. Examples of that are the ways that Fox News and WUWT have a history of being ‘more biased to be misleading’ than the diversity of sources pointed to by SkS (which also all have a bias).

The efforts you are asking for already exist. And they have existed for decades. Note that the report and its 80 recommendations are substantially based on the following sources of improved awareness and understanding: The UN Development Programme, the Sustainable Development Goals, and the IPCC Reports. Many political groups, other leadership contenders (business and political), and advocacy groups are aligned with the pursuit of that type of learning and participated in developing the improved understanding.

The problem is not a lack of effort to increase awareness and improve understanding of how to be less harmful and more helpful. The problem is the success of efforts by people who have interests that are contrary to that type of learning.

In addition to the many helpful actions of the SkS team, a broad spectrum of books help understand why learning to be less harmful and more helpful is not more popular. I am especially biased towards (fond of - like) “The 9.9 Percent” by Matthew Stewart. "The 9.9 Percent" is an evidence-based book (loads of references) that does of good job of explaining how the most powerful 0.1% win by getting unjustified support from the rest of the top 10% (the 9.9% who also want to maintain unjustified perceptions of status relative to Others). It includes understanding that the actions of the undeserving top 10% are excused by a portion of the remaining 90% because of divisive misunderstanding appealing to ‘personal biases’ that motivates them to try to be 'perceived to be higher-status' like the unjustified top 10%.

In a nut-shell the required solution involves compromising the ability of the undeserving among the top 0.1 Percent (in wealth and power) to get support from, or be excused by, the top 10% or any of the 90%. Note: 0.1% of the current global population is 8 million. And 10% is 800 million. So over-coming the power of the most unjustified 10 Percent is a massive challenge.

Things are improving in a sputtering way like: two steps up, three steps back, two more steps up, then another step up, then a step back. Undeniably faster improvement would be better (lots of damage to Others caused by delayed reduction of harm done by the Few). However, the tragically slow improvement, and resulting larger amount of damage done, is not the fault of, or due to, a lack of effort by the people pursuing being less harmful and more helpful to others.

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Rabelt at 16:42 PM on 18 October, 2023

Bob Loblaw,

I have no interest in losing time with people like you so I will imitate your infantile behaviour and just scream IPCC report, good luck with finding anything in those 2k pages reports

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Bob Loblaw at 07:21 AM on 18 October, 2023

Rabelt @ 40., 41.

All I see is your narrative. It does not resemble any scientific narrative. In comment 22, when you introduced "main narrative", you said:

...so I will continue using the main narrative (IPCC, NASA, CSIRO, etc) as the argument I am debating

Since you want to use the IPCC as a source, please show the sections of the IPCC reports that illustrate this "main narrative".

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Rabelt at 06:39 AM on 18 October, 2023

Bob Loblaw,

Now show me where does the IPCC address those changes in the trends, or where in this great library of knowledge there is an explanation fo them.

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Rabelt at 06:37 AM on 18 October, 2023

Bob Loblaw,

Already said what the main narrative had to say about C13, comment 34.

If you want the entire narrative, you have the reports of the IPCC.

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Bob Loblaw at 04:33 AM on 18 October, 2023

Rabelt @ 28: "quote which part I said anything dismissive about the carbon cycle."

The fact that you say virtually nothing coherent at all about it - when it is essential to understanding the graph/data you criticize - is all the evidence that is needed.

@ 29: "I love how the guy putting words in my mouth is acussing me of strawmaning his arguments,"

I am not accusing you of strawmanning my arguments - you have strawmanned "the main narrative" (in the context of what climate science - e.g., the IPCC - has said). If you want to provide a counter-argument, you need to give a thorough explanation of "the main narrative" (including the carbon cycle). Until you provide actual evidence that you have at least a basic level of understanding the carbon cycle (not just an assertion), then you're just blowing smoke.

Also @ 29: "Quote my comments and explain why they follow your supposed "logical consequences"

I did quote you, in my comment 19.

You finish with "I said Delta changes previous to human emissions following co2 concentration not FF emissions as there were none, and the ones that existed were accountable for insignificant amounts of co2." The way you have worded this suggests that you think that either CO2 concentration changes cause C13 changes ("delta changes ... following CO2 concentration"), or that C13 changes cause CO2 concentration changes ("delta ... accountable for ... CO2").

You have not responded directly to that, to provide any sort of clarification or indicate what you really meant. Yet you come back with "Again, never said co2 concentrations cause changes in Delta C13..." From this view, it looks as if you are just dodging the question.

And now you are stating "Differences in the carbon cycle are expected, yet only are accepted if they dont contradict the main narrative,"

Congratulations. You have now scored a third point on FLICC - the 5 techniques of science denial. - Conspiracy theories.

Since you clearly are unable to actual specify what "the main narrative" is, your speculation about what contradicts it is not worth the electrons used to transmit it.

And finally, @ 30 "I am talking about emissions not co2 concentrations"

Yet the graph that you began this whole flood of nonsense over is a graph that shows two things as a function of time: CO2 concentrations, and C13 isotope ratios. There is no coherence or consistency to what you say. Buy a clue please: CO2 concentrations, CO2 emissions, CO2 uptake - all are part of the carbon cycle that you keep dismissing. Oh,, sorry - not "dismissing" but just "ignoring".

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Rabelt at 18:30 PM on 17 October, 2023

Rob Honeycutt,

During the period 1750-1850, more specifically 1750-1860, there is the start of the industrial revolution as the IPCC says (1750) to 1860, an arbitrary point of time that I am using because the cumulative co2 emissions reach the 7.8 GT of co2 necessary to increase the co2 concentrations 1 ppm, also because its 100 years roughly; during this period there is a downward trend, yet the annual and cumulative emissions are too small to create any perceptible change, so it seems strange that we can see that trend and we can see that following periods, such as 1850-1900 and 1900-1950, show a very similar trend yet the annual and cumulative emissions are tens to hundreds of times bigger; I would expect a faster trend the bigger the emissions, not a 1 to 1, but there is no big change that correlates them.

From the eMail Bag: Carbon Isotopes, Part 2: The Delta Notation

Rabelt at 18:14 PM on 17 October, 2023

Bob Loblaw,

You dont have any authority to say what the main narrative says, so I will continue using the main narrative (IPCC, NASA, CSIRO, etc) as the argument I am debating, not your fantasy.

Delta C13 is a measure that follows the emissions spectrum from human activities, there is no exact correlation indeed, that is what I am arguing, that it doesnt even follow a trend, it follows the co2 concentrations, If we look at the period 1000-1750 (pre-industrial), we can see variations in co2 concentrations are followed by Delta changes, when we look at the other periods, that you are incapable of addressing, we see the same behaviour, Delta follows co2 concentrations not emissions; the narrative from IPCC and similar say that Delta should follow the trends in co2 emissions.

You continue to mention sources that respond and address nothing I say, they dont explain the difference in trends from Delta and co2 emissions, they are explaining the same things as this post (part 1 and 2); Part 1 is irrelevant to the trends in Delta and co2 emissions as it is a physics class, nothing else, maybe read the post and then comment, it would help.

Your interpretation of my statements is irrelevant to what was written in them; I never said the period 1000-1800 is related to post 1800 periods, I exclusively talked about the relation in co2 concentrations and Delta trends in that 800 years period, that you cant read or comprehend is not my problem. Quote the specific part where I said what you accuse me of saying.

The Carbon cycle can affect co2 concentrations and Delta C13, yet your narrative dismiss this and exclusively accuses the change to FF, from 1750-1860 the cumulative CO2 emissions are 8 GT, or the equivalent to 1 ppm, while the change in co2 concentrations was 9 ppm, that presents a mechanism that is not human action that can, and does, change the values and trends from Delta C13 and co2 concentrations.

Climate Confusion

Bob Loblaw at 23:08 PM on 30 September, 2023

Markp lost any remaining credibility when he started comment 51 with "IPCC apologists".

From wiktionary:

apologist(plural apologists)

1. One who makes an apology.
2. One who speaks or writes in defense of a faith, a cause, or an institution

Markp's choice of nouns leaves the impression that he thinks of people that disagree with him as defending a faith or a cause. He'll probably say that he meant the third version - defending an institution - but the dog-whistle of "apologist" (rather than other possible choices, such as "defender") tells us more about him than it tells us about his opponents in the discussion.

Climate Confusion

Rob Honeycutt at 03:40 AM on 30 September, 2023

Markp... Who do you think should be taking action on climate change and how do you think they should endeavor to do it?

I would note that, somehow, I guess inconceivably, government-led action is how we ultimately solved the crisis related to emissions of CFC's.

Mark, you might also want to note the IPCC doesn't have any power to regulate anything, nor can they implement any solutions. They are merely the intergovermental body that communicates the science, risks and impacts we face.

It's the UNFCCC at the COP conferences where goverments meet in attempts to create agreements that would address the problem. And those agreements are non-binding agreements between nations. The Paris Agreement was a product of the UNFCCC.

What is not clear in your post is, what do you think William Carton is saying?

Climate Confusion

Markp at 22:40 PM on 29 September, 2023

For all you IPCC apologists, I found a nice piece of research that will help those with their thinking caps on to better appreciate the problems with refusing to accept that this government-led body is not acting in our best interest the way you may think it is. This comes from Wim Carton of Lund University in Sweden. His article Carbon Unicorns and Fossil Futures; Whose Emission Reduction Pathways Is the IPCC Performing? appears in the book Has It Come To This? The Promises and Perils of Geoengineering on the Brink, (2021) Rutgers University Press

2nd law of thermodynamics contradicts greenhouse theory

Likeitwarm at 04:38 AM on 28 September, 2023

Sysop, Thank you for allowing this conversation with scaddenp and myself to continue.

1562 scaddenp
You said "What I am asking is whether you can remember what switched you into looking for sites like CO2Science or temperature.global? Was it just disbelief about trace gases or were there other considerations?"

I've been thinking about an answer for you.
I started looking into "global warming" back in the mid 2000s, 25 years ago,
I think with this site https://www.geocraft.com/WVFossils/ice_ages.html.
Many other places and books since then.
I find a lot, 1000s or more, of scientists that disagree with AGW.
One is Nasif Nahle who has calculated the emissivity of CO2 at less than .003 and and says that it doesn't absorb or emit much if any IR. You can see his calculations at https://jennifermarohasy.com/2011/03/total-emissivity-of-the-earth-and-atmospheric-carbon-dioxide/
Then there is the Club Of Rome, a bunch of rich elitists that think they know best for the rest of us. Back in 1968-1974 they decided they needed a scare tactic to get people to reduce births, thus reducing the population of the earth and the resources used by them. They settled on AGW because CO2 is emitted when fossil fuels are burned. Reduce the available energy and you will reduce the birth rate.
The U.N. IPCC was not charged with finding out what makes the climate change but rather how to pin it on human causes. See https://shalemag.com/manmade-global-warming-the-story-the-reality/ and https://principia-scientific.com/the-club-of-rome-and-rise-of-predictive-modelling-mafia/
UN’s Top Climate Official: Goal Is To ‘Intentionally Transform the Economic Development Model’
https://www.investors.com/politics/editorials/climate-change-scare-tool-to-destroy-capitalism/
You see, the goal was not to save us all from overheating the planet or acidifying the oceans. The goal was to scare everyone into giving up cheap fossil fuels.
I don't know what the goal of you and your colleagues at Skeptical Science is but I do know you can create logic and equations to describe anything, so I remain skeptical of your site.
Now you know where I'm coming from. See www.ourwoods.org.
Cheers

John F. Clauser: the latest climate science-denying physicist

sailingfree at 22:38 PM on 15 September, 2023

Good thoughts on the IPCC, but back on topic, Clauser:

The recent article in Epoch Times is at https://www.theepochtimes.com/us/nobel-winner-refutes-climate-change-narrative-points-out-ignored-factor-5486267?cmt=1&cmt_id=bc9ade40-335a-4574-b934-27a8bb64dd4b

It is depressing to me to see the spread of such blatant crap. To get really upset, see the comments there for a view into the minds of deniers.

I hope that readers of skeptical science can add comment and replies to that article to help balance the propaganda and even get some deniers thinking of the real science.

John F. Clauser: the latest climate science-denying physicist

Leonard Bachman at 21:54 PM on 11 September, 2023

Per the IPCC reports, dare I mention that review articles are often exceptional examples of research. Organizing, theming, and critiquing the body of current understanding does itself create new understanding and further direction... aka: research.

There is no consensus

Eclectic at 18:27 PM on 10 September, 2023

RicardoB @950 :

thank you for the link to Jordan Peterson's YouTube interview with Dr Judith Curry [made February 2023]. Thank you ~ sort of ~ but alas the video is one (1) hour plus 34 minutes long.

Warning. I didn't get much farther than 35 minutes into the video, before my patience ran out. Dr Curry seemed her usual rather vague & waffly self . . . a blend of half-truths & suggestive propaganda. [See my comments at post #949 , above.] If she or Dr Peterson have anything highly worthwhile to say in the remaining hour of the video ~ then please time-stamp it so I can go look at it.

Shortly before I gave up entirely, Curry at 38:40 said**: "at least over the next 3 decades, like the natural variability piece of this is pointing towards cooling ... [which] would tamp down the [CO2-caused warming]".

** My comment is that this is routine lawyer-advocate rhetoric coming from Curry ~ she has almost no evidence to support this "looming cooling" in the next 3 decades . . . but it sounds good to the gullible Denialist listener . . . and if real climate scientists challenged her, she would simply stand back and say (approx) "Oh I didn't say the world would cool, I just said the expected anthropogenic warming would/could/might be somewhat lower than the IPCC expects." [Which seems likely to be 0.5 degreesC hotter than 2023 ~ barring a sustained heavy asteroid bombardment.]

# At the start of his video : some minutes of Petersonian waffle ~ he may have (as a psychologist) some personal insight . . . but it seems to get overridden by his desire for limelight (such is his multi-year track record).

At 19:30 , Dr Jordan Peterson shows how little he knows about climate matters ~ fair enough ~ but why is he choosing to boost Dr Curry?

At 23:30 , Dr Curry makes vague & fluffy reference to cloud effects. And goes on to say: "we don't know how sensitive the climate is to increasing CO2"

At 24:35 , Curry goes on to suggest: "... the oceans and the sun that are the biggest sources of uncertainty in understanding what's going on ..."

RicardoB , you can see why I regard most of what comes out of Dr Curry's mouth as being very often slanted towards insinuations of a vague or semi-deniable type, well-suited as grist for Denialists.

But, if there's anything good in the last one (1) hour of the video . . . then let me know !

John F. Clauser: the latest climate science-denying physicist

nigelj at 07:56 AM on 10 September, 2023

Eclectic @14 some of these physicists come across as very arrogant and over confident, and seem to think that because physics is the most fundamental of the science it makes them experts at everything, without having to study the detals of other issues, like the climate issue. And with the climate issue the details are particularly important. I assume thats sort of what you mean by Happer-Giaever syndrome.

Yes the IPCC reports are a rich lode of information. I can see a great deal of work has gone into these and I get a bit defensive when they get criticised, and especially when the motives of the authors get criticised.

The IPCC scientists are volunteering their time, and yet they get slammed by paid professional deniers with their junk science, and also slammed by a few people at the extreme edges of the warmist group, who think the IPCC should immediately and uncritically embrace the latest and most doomy study. Makes me furious. And I say this as someone who has a doomy disposition or bias, but at least Im aware of the potential for that to sometimes get out of control.

John F. Clauser: the latest climate science-denying physicist

Eclectic at 08:37 AM on 9 September, 2023

Nigelj @12 ,

Agreed. Michaux seems determined to assert that "renewables" are an impossibility, or at least a cul-de-sac, on the path to electricity generation of the non-fossil-fuel type. But the adage is :- half a loaf is better than none . . . it would be foolish not to go the path of wind/solar, while we are gradually developing newer technologies.

@13 : Clauser appears to be a climate neophyte, suffering from the Happer-Giaever syndrome. One wonders at his choice of ignoring the rich lode of information available per the IPCC.

John F. Clauser: the latest climate science-denying physicist

nigelj at 06:46 AM on 9 September, 2023

The IPCC reports are clearly conservative leaning. However the latest IPCC report does project warming at around 4 - 5 degrees by end of this century at BAU (Business as usual emissions) and SLR (sea level rise) worst case up around 1 - 2M end of this century. And it will go on rising after that if we do nothing.

There are lower SLR projections out there and a small number of higher projections by people like Hansen at around 4M end of century, but his is very speculative. So Im not sure that the IPCC are being excessively conservative on the key numbers.

For me SLR projections of 1 - 2M end of this century look very worrying with the potential to cause massive problems. Even although 2M is worst case and low probbaility the impact is potentially huge so such a scenario should be guiding or mitigation response. If people cant see all this and feel motivated to take serious action, then I'm not sure they would change their attitude if the number was 4M anyway.

So obviously the IPCC should robustly communicate the climate problem, but I think we are at risk of scapegoating the IPCC for the lack of strong mitigation response, when the culprit is really peoples complacency, due presumably to numerous factors from vested interests, resistance to change, psychological barriers, ideological views, the denialist campaign etc,etc.

John F. Clauser: the latest climate science-denying physicist

MA Rodger at 21:25 PM on 7 September, 2023

Markp @1+,
I think it is wrong to say that the IPCC is not a scientific body. Certainly the SPMs are edited for the political purpose of obtaining unanimity, but the assessment reports do reflect the whole of the science and thus are scientific. If that science is not being done (and in the case of WG2 & WG3 I fear it probably isn't), it is a problem not of the IPCC's making.

The two examples you provide are worthy of discussion.
☻ Spatt & Dunlop (2018) 'What Lies Beneath; The Understatement of Existential Climate Risk' is a bit of a gallop through the subject and today a little dated. It is the product of a think-tank and, apparently, "is not intended as a 'scientific paper'." Perhaps study of missing threats should become a subject set up as a science; the studying of the cracks within AGW science.
Today the science (and thus the IPCC) is addressing tipping points and if the evidence suggests either of them are still underplaying them, then that should be put on record.
And the 'fat tail', our inability at nailing down ECS and partcularly the top end of possible ECSs; if that does continue to remain elusive, isn't that because the 'fat tail' acts so slowly? And if it is slow and also temperature induced, presumably we should be able to dodge it before it arrives.

☻ The second example you cite is a downloadable undergrad thesis and the climatology bit of it is about the rather dated 'Arctic melt-out' warnings of two-decades back. At the time the basis for these warnings was the period of increased melt 2000-07 which saw previous trends in annual Arctic minimum SIE rise from -0.06M sq km/y to -0.24M sq km/y. The idea that the thinning ice would disappear with a rush was at the time** not unfounded but it hasn't been borne out with 2007-on only showing a slow downward trend in the Arctic SIE minimums.
(** I remember at the time the widespread incredulity given to 'official' projections which were suggesting ice-free Arctic summers would arrive more slowly, sometime 2027-50. We are now not far off from the start of that period and no ice-free event yet.)

The other bit of criticism of in the undergrad thesis looks at economic forecasting. This is perhaps off-topic (the numpty Clauser is the topic here & he is a science guy) so I'll try not to wax too lyrically.

I don't think the thesis really scratches the surface in its descriptions of what I consider ligitmate criticism of the pretty awful work in this field. The idea that timely AGW mitigation would (according to denialists) crash the global economy and pauperise the less-developed world but AGW itself would do no more than slow economic growth marginally (global growth reduced by just a third under +4ºC AGW in the doomiest projection here) I find utterly unbelievable. (My usual example is to imagine Madagascar melted into the sea. The loss to global economy would be 0.014% but would the 30M souls who live there just go down with the ship?)
But with the numpty Clauser as the topic here & he a science guy, economic forecasting is not on-topic here.

John F. Clauser: the latest climate science-denying physicist

Doug Bostrom at 08:53 AM on 7 September, 2023

"Your logic would also have us stop trying to change flaws in our law courts and legal system, flaws in our election system, ad infinitum, because "what we have works and they are doing their best."

Mark, as you're upset about the direction this discussion has taken let's just note that you've invented a situation wherein we claim the IPCC is perfect and not subject to improvement.

I'm familiar with Spratt & Dunlop's brief. It's critiquing the IPCC process, methods and results against an imaginary purpose for the organization.

Spratt & Dunlop's conclusory remarks are notably lacking in any concrete prescription of actionable, practical advice for remedy. They are unhappy with what exists but apparently are not able to conjure a better substitute.

With critics failing to deliver a plan for how progress might appear, the reader is left with a false impression; no additional communications vehicle is suggested by the authors, so surely the solution lies in altering the subject of the critique so as to address the authors' untethered objections to the IPCC. If so, what happens?

As Schellnhuber points out, what's missing from the IPCC is reports is imagination divorced from a continuum of evidence (possibility vs. probability). There's a role for unsupported extrapolation, but that's an additional communications task that if commingled with strict evidentiary requirements will quite arguably leave the entire process of dealing with climate change even more amenable to misinformation and disinformation than it is today. Notably and despite such critiques as the one we're discussing here, the IPCC is the subject of concentrated, prolonged polemical attacks on its credibility from the side of the fossil fuel industry and other enthusiasts of unaccounted external costs. Arming such rhetoricians with valid grounds for their own purposes of critique wouldn't be a smart move.

It would be nonsensical to claim that no improvement is possible in the IPCC process and methods. Fortunately nobody here is making that claim. But improvement doesn't include introducing science fiction into the foundations of IPCC reports, and it's hard to see how bringing possibility divorced from probability into the IPCC's work would be other than exactly that. We're blessed with imagination and can and should exploit it, but here our imagination needs a solid tether— as a separate feature— because imagination comes with degrees of credibility and here credibility is mandatory.

John F. Clauser: the latest climate science-denying physicist

Markp at 02:30 AM on 7 September, 2023

Bob "Oh my" Loblaw

I don't need a lecture on how the IPCC works. Thanks. I did not say the IPCC provides analysis "in the sense of crunching data, etc," now did I? Read what I wrote, please.

As for "what information? What flaws?" maybe if you'd READ the papers I linked to, you would find out. I'm not inveting this. And please don't put words in my mouth, either: "some people say"?? Please see if you can find that in my text. Talk about "weak"!!!

I'm happy to check on this site for the new items it brings but I think I'm finished discussing the reality of how much we have not managed to do to stop climate change with people who have their heads in the sand.

John F. Clauser: the latest climate science-denying physicist

Markp at 02:17 AM on 7 September, 2023

Michael Sweet

"Doomers" is a word with little value or meaning and has become similar to "conspiracy theorist" where people apply it to those whose views they do not like.

I'll bet you haven't read, for example, What Lies Beneath, one of the papers I linked to. The foreward was written by Hans Joachim Schellnhuber, professor of theoretical physics specialising in complex systems and nonlinearity, founding director of the Potsdam Institute for Climate Impact Research, and former chair of the German Advisory Council on Global Change. He is not a doomer. People who want the IPCC to be improved are not necessarily "doomers" or cranks. It's really too bad you and others here seem unable to accept that this government organization is not perfect and could be made better.

You say "if all scientists take your attitude..." well guess what? My attitude is to do what I can to stop the warming, which is why I work for a climate science nonprofit to do just that, and not by handing out leaflets asking people to turn off the lights, but by helping an organization that is currently helping the poor in the Global South live more comfortably by converting their roofs into cool roofs, for free. And it's not just white paint. And that's not all. So please.

John F. Clauser: the latest climate science-denying physicist

Bob Loblaw at 22:26 PM on 6 September, 2023

Markp @ 3:

Oh, my. The IPCC does not provide analysis in the sense of crunching data, etc: it collects information from the published scientific literature, and provides a broad overview of the status of the science. It does not do any new research of its own. All the material it presents is based on other publications and research. The authors of the IPCC reports are a subset of the authors that work in climatology, but ultimately the science itself comes from the literature. If you don't like what the IPCC says, you can always go into the literature and see what it says for yourself.

The "Summary for Policymakers" documents are more subject to political pressures. That is where things will get watered down, spin applied, etc. If you disagree with them, look in the full reports for details. If you don't like the full reports, read the literature.

When you say things like "However, much of that information is deeply flawed, according to scientists both inside and outside the organization", expect to get challenged. Such a vague accusation is pretty much worthless in a serious discussion. What information? What flaws? What scientists? What positions do they hold? Most of the IPCC participants are not "members of the organization" - they do this work as part of their normal employment elsewhere. I have worked with people that were involved in the IPCC process. They did not get paychecks from the IPCC. They did not have IPCC membership cards.

"Some people say..." is such a weak, weak, weak argument. Some people say all of science is corrupt. Some people say evolution is wrong. Some people say the world is flat. Some people say the Easter Bunny is real.

To make this vaguely on-topic, John F Clauser says things that are simply way off. Just because he says it does not make it remotely true.

John F. Clauser: the latest climate science-denying physicist

michael sweet at 21:49 PM on 6 September, 2023

Markp,

Certainly there are scientists who are doomers like the ones you have linked. The IPCC reports give the low end of scientific thought on warming problems. This was a political compromise. You are correct that the majority of scientists think it will be worse than the IPCC says.

Everyone agrees that 3C warming will be much worse than 2C and 4C will be much worse again. We have to do everything we can to reduce CO2 pollution as much as possible. While we have missed the 1.5C target, we still benefit from the reductions that have taken place.

There are already many people who have given up on trying to solve the warming problem. They think it is too hard. If all scientists take your attitude then it is likely that most countries will give up and the problem will be worse. Scientists like Michael Mann and Gavin Schmidt know that the situation is very bad. They act to get as much response as possible from governments.

I saw this quote today in CNN:

"Samantha Burgess, deputy director of Copernicus, “The scientific evidence is overwhelming – we will continue to see more climate records and more intense and frequent extreme weather events impacting society and ecosystems, until we stop emitting greenhouse gases,”

How can she say anything stronger?

John F. Clauser: the latest climate science-denying physicist

Markp at 18:14 PM on 6 September, 2023

I'll admit that the IPCC is the largest organization producing climate analysis, and as such provides the overall best information we have. However, much of that information is deeply flawed, according to scientists both inside and outside the organization. Is it wrong to want that corrected? Because that's all anyone is saying.

Your logic would also have us stop trying to change flaws in our law courts and legal system, flaws in our election system, ad infinitum, because "what we have works and they are doing their best."

Have you read either of the papers I've provided links to? If you haven't, it's unlikely you know anything about the problems you are trying to close everyone's eyes to.

Once again, you do not do yourself favors by refusing to be realistic about the good efforts that have been made to fight climate change, and to pretend there is nothing wrong, or to hold that to say so is some kind of blasphemy, or is unfair or unkind, and to suggest that rather than try to shed light on things that need improving if we are to have a fighting chance here, that we should just keep our mouths shut, close our eyes and offer thanks and praise.

John F. Clauser: the latest climate science-denying physicist

Doug Bostrom at 03:04 AM on 6 September, 2023

"...one of the world’s greatest scientific bodies."

Name a functional equivalent that produces a more competently comprehensive synopsis of how Earth's climate functions and how we affect its functioning.

"It is composed of the world’s foremost climate scientists, who every 5 to 8 years devote tremendous amounts of time and effort to author reports summarizing the latest climate science research, without any remuneration whatsoever."

This is objectively correct.

"The IPCC reports are in fact the world’s best source of accurate and valuable climate science information."

Name reports on climate (or anything else) that are more comprehensive and also accurately reflect "here's the best we know at this point."

The IPCC exists, the first and most important virtue. It's a concrete feature, as opposed to wishful desire for a system for dealing with human nature that is divorced from human factors.

Meanwhile, haggling over the messaging, the messaging ending up acceptable to multiple countries with multiple often conflicting self-interests? Is this a defect? If one bothers to read its self-stated mission and purpose, one will learn that the IPCC specifically exists for the purpose of colliding geopolitics with science. To expect the IPCC to remain aloof from geopolitics is to doom it to have no connection with or influence over geopolitics and the behavior of individual states.

The IPCC has since its first report steadily produced warnings over our influence on climate that have over the course of the years increased in stridency and urgency, a surfeit of actionable advice. The parsimonious methods of the IPCC have yielded all the information we've needed to act on and attempt to check our climate disaster. But the IPCC does not operate governments, it informs them. There's plenty of information emerging from this sausage factory, only consumed very slowly because it's emerging into a world full of interactive, reverberating other problems of human nature.

There's a lot of inchoate frustration over human nature and Earth's climate floating about these days, looking for its proper home. Keep looking.

Meanwhile Skeptical Science will try to stay in the tank of reality, where feet wade through clay as best as they actually may.

John F. Clauser: the latest climate science-denying physicist

Markp at 20:47 PM on 5 September, 2023

Scientists are human beings like everyone else, and while that explains much of the disagreement one can find among scientists on all sorts of topics, when people like Clauser come along and speak outside of their area of expertise, flatly contradicting the work of the majority of those directly involved specifically in that field, as in this case climate science, it really makes you wonder what motivated them to do that.

Honesty is important for everyone involved on the subject of climate science and global warming, of course, including those in the mainstream. The characerization of the IPCC here, for example, is so glowing, one might think it was written by the IPCC itself "one of the world’s greatest scientific bodies. It is composed of the world’s foremost climate scientists, who every 5 to 8 years devote tremendous amounts of time and effort to author reports summarizing the latest climate science research, without any remuneration whatsoever. The IPCC reports are in fact the world’s best source of accurate and valuable climate science information."

In fact, the IPCC is arguably not a scientific body: the "Intergovernmental Panel on Climate Change" is, as the name implies, a governmental body, where scientists volunteer their work but must in a way "compete" with political appointees from 195 UN nations to haggle over messages delivered to policymakers. It is well known that those political agents have rejected and softened language in statements proposed by scientists numerous times, when that language was deemed problematic for their individual nations.

But it goes further than that. The IPCC in fact has been criticized, not only by cranks like Clauser, but by its own contributors as well as other, reputable scientists in the climate science field, for being far too cautious, particularly in their characterization of the speed and severity of the effects of climate change from global warming. Being on the "right" side of this debate between the mainstream climate science "community" and people who are clearly climate deniers, should not mean that those defending what scientists have discovered need be deniers themselves of the many errors and misinformation that has been produced by organizations like the IPCC.

Papers such as "What Lies Beneath; The Understatement of Existential Climate Risk" by David Spratt and Ian Dunlop, and "Faster Than Expected; The IPCC's Role In Exacerbating Climate Change" by Kyle Kimball, are a good start for those interested in examining clearly documented errors and pattern-forming cases of inaccuracy on the part of the public messages delivered by the IPCC.

It is one thing to be an outright climate denier. It is another to be one who so stridently opposes the outright frauds and fakes that one refuses to admit, and even attempts to hide or gloss over the real problems that do exist within what people call the climate science "community" and those various organizations responsible for gaining insight and finding solutions for humanity to fight what may someday soon be legally recognized as the ecocide perpetrated by numerous energy companies when they were warned numerous times by scientists of the need to swiftly switch to alternate fuels, and chose to bury, manipulate and deny that science in order to focus on business as usual and the maximization of shareholder value.

Climate Confusion

Rob Honeycutt at 04:19 AM on 5 September, 2023

Markp... When I say "new tech" what I'm alluding to is new materials. Replacements for cobalt. Potential for, say, solid state batteries. New methods and materials for the production of solar panels.

You can fall off your chair all day long, but people are continually working on better ways to generate energy. There is no lack of ingenuity being applied to these problems.

I think this illustrates the potential problem with your evaluation of the issue. If you look at any of this as steady state and extrapolated forward from there, you're inevitably going to end up with a doomsday scenario. But, as I've stated from the start, things are happening. Smart people have been working hard on these issues for decades and it's bearing fruit. The IPCC's work has been instrumental in keeping that ball moving forward though international agreements.

The task remains nothing less than Herculean, but it is wholly inaccurate to suggest that nothing has happened.

I tend to harp on this issue quite a lot because I believe rhetoric suggesting nothing has happened leads people to give up, right when we need people to understand that real progress is being made.

Climate Confusion

Markp at 00:47 AM on 5 September, 2023

Rob, thanks for the chart, but merely looking at a cost comparison between FF and renewables overlooks a lot. Have you seen Michaux's paper on this? You can find it here. It's a large report but worth looking at.

The report is called "Assessment of the Extra Capacity Required of Alternative Energy Electrical Power Systems to Completely Replace Fossil Fuels." One of his conclusions is that the amount of metals required far outstrips current reserves to build the needed infrastructure for the first generation of such a "transition" only (1st generation needs to be mined because until it's been built there is little to recycle). He writes: "Current expectations are that global industrial businesses will replace a complex industrial energy ecosystem that took more than a century to build. The current system was built with the support of the highest calorifically dense source of energy the world has ever known (oil), in cheap abundant quantities, with easily available credit, and seemingly unlimited mineral resources. The replacement needs to be done at a time when there is comparatively very expensive energy, a fragile finance system saturated in debt, not enough minerals, and an unprecedented world population, embedded in a deteriorating natural environment. Most challenging of all, this has to be done within a few decades. It is the author’s opinion, based on the new calculations presented here, that this will likely not go fully to as planned."

So even if wind and solar energy is cheaper than FF, we may not be able to replace FF with them, even if the IPCC says "we MUST."

Thanks also for the IEA link to "Net Zero Emissions by 2050" but this is a big paper. When I asked you how you thought this could be done, I asked for a few bullets. I will have a look at the paper, but my fear is that, as Simon Michaux's has pointed out, a lot of the "plans" for a better climate future have, amazingly, been made without consideration for the reality of time, energy, resources, etc. So they contain bold statements about what MUST be done, as if saying it is all that's needed. Like I said, I'll look at it but I'm not going to be surprised if I don't find a realistic assessment.

Climate Confusion

Rob Honeycutt at 04:09 AM on 4 September, 2023

Markp... The conversation gets unweildy when you do such long posts. Can you please try to engage in a bit more editing to get your comments better focused? I think it would improve the value of this exchange.

I'm only going to address your first observation here: "'A lot is happening towards decarbonization' is vague enough to require examples to qualify the statement."

I'm sure there is a better thread for this but, if the mods will allow, I'll just post a response here for now.

First is the mere fact that onshore wind and solar are now cheaper than FF sources. This is relatively recent yet is already starting to show benefits in the energy marketplace.

The result of this is now renewable energy is scaling exponentially.

Bear in mind, this is still the early phase of exponential growth, so the true effects of that growth are going to be realized out past 2030-2050.

In the latest EIA LCOE (levelized cost of energy) reports they're now including battery storage technologies because those costs are now falling in line with peaker plants.

So, to try to somewhat tether this to the topic at hand, these technologies are the product of decades of very hard, complex work done by a lot of very smart people. These are the fruits of those efforts. This is why I say, while there are still many large and looming challenges, there is a lot of positive change afoot that should not be ignored.

These advances are very likely a product of the sorts of communications and political engagement done over the years by the IPCC and various resulting international agreements. It would have been unlikely any of these advancements would have occurred with out the IPCC's work.

These are the kinds of advancements that have to occur in order to get to net zero and then eventually zero carbon emissions by 2050 and after.

Climate Confusion

Markp at 05:22 AM on 3 September, 2023

Hello

No, I'm not at all advocating that individuals adjusting their lifestyles are the answer, far from it (I'm surprised to hear this from you!), but it is something that must be done. Average people pushing the politicians and business leaders to act is necessary as well, because as we can see, without that they'll continue making targets and holding discussions that don't get us anywhere.

This is going to come down to us agreeing to disagree, I guess, for example regarding the IPCC and all the supposed "progress" we've made. I know that most people in climate science (scientists and others) think like you, that a lot has been done, etc. I just don't buy it. We've certainly managed to elevate the overall knowledge of GW among everyone - people from all walks of life (not with the honesty and clarity that is needed in my opinion, but...). But that has not translated into the kind of action we need by a LONG shot. It's politics and it's scientific reticence (i.e. David Spratt) and many other reasons, but it's there, staring us all in the face. Maybe I'm just speaking here to the optimists, 45-years of experience or not. I don't know. But if you think you shouldn't take me seriously because of my attitude towards models re "the end of temp rise" I'll just reiterate that it's not just me but people like James Hansen who have expressed those opinions. Just look at his latest tidbit: "Equilibrium Warming = Committed Warming?" where he writes in the 4th paragraph: "...climate science should be focused on data. That's the way science is supposed to work. However [the] IPCC is focused on models. Not just global climate models, but models that feed the models, eg. Integrated Assessment Models that provide scenarios for future GHG levels...sometimes the models contain hocus-pocus. As we mention in our current paper, they can assume, in effect, that 'a miracle will occur.'" And as you know, he's not the only one to criticise the overreliance on models. I'm assuming you are all familiar with Spratt and Dunlop's "What Lies Beneath."?

At the end of the day, scientists are no different from anyone else in this world where we all have to struggle for survival and protect our jobs and reputations and do things we have to do but may not believe in. Research isn't done for fun or for pure curiosity unless one bankrolls one's own laboratory, which few do. It's done to support the money, make a product, build a name for oneself, etc.

So people like (unnamed) set up for-profit companies as sidelines in addition to their responsibilities with their universities and, look what he just did: sold Carbon Engineering for over $1B. Nice. Ka-ching. You can't sell simple solutions for that kind of money, can you? And Climeworks, when are they going to have an IPO and cash-out, for worthless DAC? And this is all because the IPCC said "We MUST do this!"

An extremely important statement from the foreward of "What Lies Beneath" is from Hans Joachim Schellnhuber, professor of theoretical physics, etc., long list of credentials, when he said we are running out of time and so "...it is all the more important to listen to non-mainstream voices who do understand the issues and are less hesitant to cry wolf [than for example those scientists working with the IPCC]".

I work with those non-mainstream scientists because they are the ones who seem to be cutting through the BS towards real solutions that give us more than hopium.

Let me just ask you, and I am trying to be fair to the scientists in climate, generally speaking, because I imagine the vast majority are really doing their best. They aren't free to do what they might if they weren't trapped in the system we all are trapped in. (I know one who is a physicist but works with the IPCC on policy and he told me once "You have to trust your institutions, Mark"!!! Really. I trust the post office to deliver a letter. I don't trust politicians to solve global disasters that require those in power taking home less money.) But let me ask: if scientists really have been trying as hard as they could for decades now to come up with ways to stop rising heat and protect life on Earth as fast as possible, why has nobody else but a man who left his academic career at Harvard behind in order to found a nonprofit been able to come up with the solution staring us each in the face every morning when we brush our teeth, involving mirrors? Could it maybe have anything to do with the fact that it is just not very sexy? Honestly, I cannot understand or explain it any other way. And I've seen big-wig scientists in the climate sphere hear of this and say "where's your peer-reviewed research?" instead of just turning their brains on and thinking about the idea first. "Hey, makes sense, pretty obvious, actually...could be some complications, but overall, interesting idea..." (Kudos to Eclectic on this one) No, instead they just wanted research to back up the idea that ice will melt in a hot frying pan.

Well...would have been more fun over a beer. Take care.

Climate Confusion

Rob Honeycutt at 03:36 AM on 2 September, 2023

Markp... "We've had the IPCC for 35 years and not much to show for it..."

Again here, you're seemingly making the claim that nothing has happened when the opposite is true. A great deal has been accomplished. A great deal more must be accomplished. You can certainly make the claim that the changes aren't happening fast enough, but you can't rationally claim nothing has happened.

Climate Confusion

Markp at 03:04 AM on 2 September, 2023

I am not a scientist, but I've been working in climate science for a couple of years now.

I wouldn't say I dismiss models, I'm just careful with them. Perhaps "garbage in, garbage out" is more common an expression to describe models in the financial world than in the natural sciences, but even so, when it comes to climate modelers I'm merely echoing sentiments from those like James Hansen, who clearly value models but prefer using real data, real-world, whenever possible. I've spoken to established research scientists who laugh off the climate modelers who so cheerfully say "temperatures will just stop rising" if net zero is achieved. These are people I trust. They've had long careers doing real science, not short ones playing with computers.

And Rob, believe me, I do live a low-carbon life myself but I know very few others know or care about the need for that. The problem is, the accepted wisdom for many years now has been to not alarm people with GW talk, and churn out messages with hope and optimism, so what has happened is that people pretty much think "the experts" are taking care of things and there's nothing to really worry about. The person on the street has no clue how bad things are or how soon things will get very bad. No wonder they don't change their lifestyles further than maybe switching to a new sexy Tesla and eating vegan once a week.

I'm also involved in the renewable energy business and that's definitely been an excellent development but again, people are being misled into thinking that's all we need to do, but it's not going to happen. Have a look at Simon Michaux's work.

We've had the IPCC for 35 years and not much to show for it, and anyone who doesn't believe that is either simply ignorant or is fooling themselves. The IPCC plays politics with science. We need to take their estimates and double or triple them to achieve results close to reality.

All I can say regarding decarbonizing is that the money and the power is dead set against it because they're only concerned about today's profits, but as more and more of the world burns up, as food insecurity gets worse and water scarcity as well, their hands will be forced. The question is: will there be enough time then? Will the "laser focus" that might (might) be squeezed out of people when their backs are against the wall be too late? What is required, at the very least since people aren't acting like adults, are laws limiting waste in all industries, in all areas of government, and in our private lives, but is that coming? Are laws restricting unnecessary consumption coming? Laws banning the worst of the world's luxury goods would put a big dent in the fattest carbon emitters and send a message to all those people idolizing such frivolous living but is that coming? We could put tight curbs on new car sales and enforce drastic changes to allowable car specifications (reduction of size/weight/horsepower). We need governments to enforce "work at home" for all industries and jobs where that's feasible. We need public service messages telling people to stop trying to "live large," we need celebrities to publically downsize their lifestyles, television shows to stop glamorizing the selfish life... the list is very long. So much needs to be done and could be done, but is it? Scientists gluing themselves to bridges is what we need, it's just about the only sensible thing to do this late in the game to make people wake up, but instead of getting the message people scorn them and governments lock them up. We cannot blame these protesting scientists. They've been asked to do something they were never trained to do, and for which no infrastructure exists, and to make matters worse, they're being pushed into solving this emergency by adopting a profit-making model that flies in the face of the spirit of science.

The way I see it, we've got about one decade of "somewhat normal" life left before the food insecurity hits the privileged classes hard, and at that point, the societal collapse that has already begin is going to be much more life-threatening than heat. Net zero goals for 2050 may no longer matter when everything begins to fall apart.

As for the mirror concept, all the details are being researched but we're not talking about traditional glass mirrors but rather "specular reflectors" such as what you get combining PET with aluminum for a cheap, thin, durable, flexible mirror-like tool. These are already in use for local heat adaptation, but going from adaptation to global heat mitigation is just a matter of scaling up, and there are plenty of resources for it, unlike so much of the other ideas floating around. Plastics with no metal at all are also being developed that could be used. The whole concept is a simple evolution of white paint, which is not feasible for many reasons including the fact that it gets moldy and needs regular attention and re-surfacing.

ClimateAdam: The Vlog Brothers on geoengineering

nigelj at 07:06 AM on 25 August, 2023

Markp @2

The IPCC do indeed have this scientific reticence. Its like a sort of conservatism. But its not just the IPCC. Science has operated that way for centuries and for good reasons.Some initial scientific findings prove to be false so the conservatism is a form of quality control. If the scientific community was too quick to endorse every new scientific finding then all its credibility would have been gone long ago, and everyone would have stopped listening long ago.

We have problems with a public backlash even now, when a theory proves to be incorrect (fortunately its very uncommon) so imagine if the scientific community was less conservative that it is. So although I'm not a conservative sort of person as such, and dislike playing down of risk assessments, I respect that its probably better that organisations like the IPCC are a little bit conservative.

That said how conservative are they? If you read their reports there are charts showing warming could reach 5 degrees this century and 10 degrees by 2300. And charts now upgraded to show that 2 M SLR is possible this century as low probability but high impact event.This does not look excessively reticent or conservative.

And do you think that adding a degree or two to those scary looking numbers would change the public perception much, and lead to stronger mitigation? I'm not seeing it. If the public cant work out that 5 degrees of warming this century under BAU is serious I doubt that saying its 7 degrees would make much difference. All we can do is repeat the implications for the planet of the official projections, explain them as well as we can, and point out the serious climate changes and the increased preponderance of heatwaves and flooding we are already seeing, and as loudly as we can.

Fossil fuel exporting countries do indeed have a malign influence on the Summary for Policy makers. Can't find the reference now but apparently some terms on levels of risk have been weakened and references to fossil fuels minimised. This is a very real concern and does mean we need to understand things are worse than the SFPM suggests. If you read beyond the SFPM and to the fine details, and the actual charts, things are not watered down in the same way. The trouble is who reads that?

Regarding your complaint that billionaires profit out of climate solutions and might have other ulterior motives, and countering this with the suggested alternative of placing solar reflectors on the ground. Its a possible climate solution, but billionaires will still make money out of this one way or the other. Its hard to escape the private sector making money out of climate solutions, given the structure of our economy. I don't care as long as the job gets done, and they are not breaking laws or profiterring as such. It would be good if they reduced their personal climate footprint, and showed some meaningful climate leadership and helped those less fortunate than themselves.

ClimateAdam: The Vlog Brothers on geoengineering

One Planet Only Forever at 02:54 AM on 25 August, 2023

Markp,

I agree that the IPCC presentation of understanding regarding 'the problem and the solutions' has been harmfully compromised by 'interests that conflict with the development of sustainable improvements for humanity, regionally or globally'.

However, IPCC is not responsible for 'promoting increased awareness and improved understanding' regarding the understanding that is compiled by the IPCC. The leaders (in political and business, globally and regionally) need to be 'held responsible' for the promotion of increased awareness and improved understanding.

The IPCC report presentation must be consistent with the available evidence. That requirement has resulted in the progressive strengthening of IPCC statements contrary to the desires and interests of the undeserving portion of leadership competitors around the planet. And the latest IPCC statement concludes that, based on the evidence, the lack of leadership action through the past 30 years has created a situation where it is almost certain that 'reasonably limiting the harm done to the future of humanity' will 'now' require dramatic reductions and limits of harmful consumption, especially energy over-consumption (desired but 'unnecessary' consumption), as well as removal of CO2 from the atmosphere - even if those actions reduce the status of people who unjustifiably developed perceptions of higher status (permitting those developing to be like the higher status people to become more harmful while requiring the higher status people to set less harmful examples for everyone else to aspire to).

The awareness and understanding that now undeniably needs to be promoted is that many of the current leaders (winners) are undeserving of their status. They have proven to be unworthy of their wealth and influence through their efforts to weaken the presentation of understanding by the IPCC which made it easier for them to actively promote 'doubt regarding the fundamental understanding of the required corrections and requirement to make amends for harm done' that is presented by the IPCC.

The current situation can be understood to be the result of a history of harmful irresponsible actions by undeserving wealthy powerful people. Arguing for 'significant climate geoengineering actions', rather than promoting the fundamental 'need to end harmful human geoengineering impacts that incorrectly developed popularity and profitability' and 'reducing the harmfully over-developed GHG levels', will not address the real problem ... it will not result in sustainable solutions.

ClimateAdam: The Vlog Brothers on geoengineering

Markp at 22:49 PM on 24 August, 2023

This is a reasonably well-done video by Adam, but there are some points that need to be made.

As many people have learned, the IPCC has done a pretty lousy job of informing the public, and the scientific views it presents have been warped both by the scientists themselves (the dreaded "scientific reticence" effect) as well as the politicians from 195 member countries that have veto power on much of the content released to the public which can be generally characterized as very, very conservative. In other words, it's way worse than they tell us, and their "solutions" not nearly as effective as they tell us. Adam and his friend Miriam are both, from what I can tell, very much cheerleaders for the IPCC. Not surprising: they are fresh out of university and so in that sense have not spent much (any?) time in the real world of working scientists, so their current YouTube careers aside, they may not want to annoy the IPCC-dominated narrative on all things climate.

Two big issues: 1) we need geoengineering more than they tell us, and 2) there is more to geoengineering than SAI.

1) Like so many climate scientists under the spell of the IPCC, (for many reasons which take too long to unpack here) Adam and Miriam accept the logic that the only necessary thing to do in order to reverse GW is to reverse GHGs, in other words, get rid of them. That's a little bit like having your doctor tell you that in order to cure your tobacco-caused cancer, you just need to stop smoking. Fighting the cause isn't always guaranteed to bring about a result in a timely manner. Reducing GHGs, yes, but who is doing that? Miriam said something like international agreements like Paris have "already reduced warming by 1C" and I say huh? All the talk of international agreements sounds good but isn't our reality, as anyone looking at our world's biggest problems today knows in an instant. Our "efforts" to reduce emissions are nowhere. It's not happening. Targets and discussions aren't enough. The point that people behind geoengineering make is: emissions reduction is not and WILL NOT happen fast enough to stop our ecosystem from collapsing. Additionally, carbon removal methods, whether nature-based or mechanical, have huge scaling problems. Yes, nature has dealt with CO2 in the past, but not like what we have now. They are very slow, are not always even feasible (tree-planting a perfect example, look at the studies) and have other issues such as water constraints making them impossible at scale. And mechanical CO2 removal is even worse. When it works, it's fast, but unscalable, with DAC being the most obvious case. So after the IPCC cheerleading stops, we have to face the music. We don't have time to rely only on the method of "turn off the tap and clean up the mess."

2) Geoengineering (you heard Adam slip in "SRM" as well, Solar Radiation Management, a type of geoengineering) is almost always equated with just ONE currently discussed method, which is Stratospheric Aerosol Injection, or SAI. That's because it's got a lot of billionaire-potential!

SAI is NOT more than a theory at this point, however. But you won't find that mentioned by many of its proponents. It is not the only way to go, is not loved by many (unbiased) climate scientists, has oodles of scientific problems to overcome if it would even work, and so is NOT the end of the geoengineering or SRM story. So Nigelj's characterization above, which makes it seem that SAI is ready-for-take-off, is wrong.

I will admit that, like the VAST majority of actual movement on climate we have seen, geoengineering efforts have a lot in common with disaster capitalism, and so should be checked out very thoroughly. Making money off of GW is the most effective thing we humans have done to date, which is a crime against humanity. Period. Governments now throwing large sums of money out for grants only on very narrowly-defined work chokes real progress. What we forget is that scientists have to get paid. Who pays them? Why? Most scientific research is arguably being funded by those who are expecting a product to patent and sell if things go well. Scientists are NOT always out there trying to find the fastest most practical fix here. The more tech that goes into it, the better. The more career-building we can get out of it, the better. That's why we see people talking about, of all things, space mirrors, as if simply putting them on the ground here to do what clouds and snow do is out of the question. There are people promoting that very idea and it has vastly more promise than any other geoengineering solution but is largely ignored (but that's changing) because it doesn't create billionaires and cannot be weaponized.

Like many things, this discussion has so much more to it than meets the eye. We need to think, REALLY think, and be realistic, and stop listening so much to government institutions (or their cheerleaders) that have almost never served anyone other than the powerful very well.

Climate Confusion

Markp at 20:25 PM on 23 August, 2023

I'm still not sold on the idea that zero or net-zero emissions implies no future warming, as Evan says "A world where the best we do is to stabilize CO2 has, for all intents and purposes, "warming in the pipeline", something that does not occur if and when we reach net-zero emissions."

First of all, it is not ultimately GHGs that determine warming, it is the EEI that does that. In other words, as I understand it, if the EEI is positive, but GHG emissions are zero, Earth still warms.

I also find it problematic that the idea of "zero emissions" or "net-zero" seems to imply to most people that all we are talking about are human emissions, when the possibility of an end to human emissions could exist while (significant) non-human emissions (for example permafrost melt) could still create warming, so that we are actually not at zero or even net-zero emissions regardless of source.

I have long searched for a really solid scientific explanation of the concept of baked-in or committed warming that carefully tries to help people understand why some scientists say it exists and some say it doesn't. But the Zeke piece (and I don't trust for-profit scientists on this) is not convincing and neither is the Scientific American piece.

Neither is the MacDougall 2022 ZECMIP study paper which clearly states "The most policy relevant question related to this research is: will global temperatures continue to increase following complete cessation of greenhouse gas and aerosol emissions? The present iteration of the study aims to answer part of this question by examining the temperature response in idealized CO2-only climate model experiments. To answer the question in full, the behaviour of non-CO2 greenhouse gases, aerosols, and land-use-change must be accounted for in a consistent way," which is another way of admitting that ZECMIP at this point is still "garbage in, garbage out."

In fact, the pieces I have found seem to rely purely on models which are always incomplete, as is ZECMIP.

And neither is this piece by Evan able to clarify this for me. Evan simply says it does not happen, as if that's been settled. He does not mention the warming, for example, that would come from the (potentially sudden? would it even matter?) end of reflective fossil fuel aerosols.

The amazing lack of clarity on this subject, which is absolutely crucial to the discussion of any need to lower emissions, is astonishing, and leads cynical people like me to assume that it is a result of the IPCC-induced obfuscation and the complete ineptitude on the part of scientists to recognize that this issue is important and to do something about providing clarity.

A Frank Discussion About the Propagation of Measurement Uncertainty

nigelj at 06:21 AM on 13 August, 2023

Eclectic @11.

I agree the cranks are a small subset of denilaists and that many of the denialists are fundamentally driven by selfish and economic motives. However you should add political motives to the list, being an ideologically motivated dislike of government rules and regulations. Of course these things are interrelated.

I have a bit of trouble identifying one single underlying cause of the climate denialism issue. It seems to be different denialists have different motives to an extent, randging from vested interests, to political and ideological axes to grind, to selfishness, to just a dislike of change to plain old contrariness. Or some combination. But if anyone thinks there is one key underling motive for the denialim I would be interested in your reasoning.

The cranks are not all deniers as such. Some believe burning fossil fuels is causing warming but some of them think other factors play a very large part like the water cycle or deforestation. A larger part than the IPCC have documented. They unwittingly serve the hard core denialists cause. They are like Lenin and Stalins "useful idiots."

I do visit WUWT sometimes, and I know what you are saying.

"To very broadly paraphrase Voltaire : It is horrifying to see how even intelligent minds can believe absurdities."

Voltaire is right. Its presumably a lot to do with cognitive dissonance. Intelligent minds are not immunue from strong emotively or ideologically driven beliefs and resolving conflicts between those and reality might lead to deliberate ignorance. Reference on cognitive dissonance:

www.medicalnewstoday.com/articles/326738#signs

This does suggests cranks might be driven by underlying belief systems not just craziness.

A Frank Discussion About the Propagation of Measurement Uncertainty

nigelj at 07:37 AM on 11 August, 2023

I enjoyed Bob Loblows article because it did a thorough debunking and I learned some things about statistics.

Some of the errors look like almost basic arithmetic and I thought a key purpose of peer review was to identify those things? They did an awful job. It looks like they didnt even bother to try.

Regarding whether such papers should be debunked or not. I've often wondered about this. Given the purpose of this website is to debunk the climate myths it seems appropriate to debunk bad papers like this, or some of them. It would not be possible to address all of them because its too time consuming.

There is a school of thought that says ignore the denialists because "repeating a lie spreads the lie" and engaging with them gives them oxygen. There is some research on this as well. There has to be some truth in the claim that responding to them will spread the lies. It's virtually self evident.

Now the climate science community seems to have taken this advice, and has by my observation mostly ignored the denialists. For example there is nothing in the IPCC reports listing the main sceptical arguments and why they are wrong, like is done on this website (unless Ive missed it). I have never come across any articles in our media by climate scientists or experts addressing the climate denialists myths. The debunking seems to be confined to a few websites like this one and realclimate.org or Taminos open mind.

And how has this strategy of (mostly) giving denialists the silent treatment worked out? Many people are still sceptical about climate change, and progress has been slow dealing with it which suggests that giving the denialists the silent treatment may have been a flawed strategy. I suspect debunking the nonsense, and educating people on the climate myths is more important than being afraid that it would cause lies to spread. Lies will spread anyway.

A clever denialist paper probably potentially has some influence on governments and if its not rebutted this creates a suspicion it might be valid.

However I think that actually debating with denialists can be risky, and getting into actual formal televised debates with denialists would be naieve and best avoided. And fortunately it seems to have been avoided. Denialists frequently resort to misleading but powerful rhetorical techniques (Donald Trump is a master of this) that is hard to counter without getting down into the rhetorical gutter and then this risks making climate scientists look bad and dishonest. All their credibility could be blown with the decision makers.

A Frank Discussion About the Propagation of Measurement Uncertainty

Eclectic at 10:44 AM on 9 August, 2023

There is a 2017 YouTube presentation by by Dr Patrick T. Brown (climatologist) which is highly critical of Dr Patrick Frank's ideas. The video title is:- "Do 'propagation of error' calculations invalidate climate model projections of global warming?" [length ~38 minutes]

This video currently shows 7235 views and 98 comments ~ many of which are rather prickly comments by Patrick Frank . . . who at one point says "see my post on the foremost climate blog Watts Up With That" [a post in 2015?] # Frank also states: "There's no doubt that the climate models cannot predict future air temperatures. There is also no doubt that the IPCC does not know what it's talking about."

Frank has also made many prickly comments on WUWT at various other times. And he has an acolyte or two on WUWT who will always denounce any critics as not understanding that uncertainty and error are not the same. [And yet the acolytes also fail to address the underlying physical events in global climate.]

In a nutshell : Dr Patrick Frank's workings have a modicum of internal validity mathematically, but ultimately are unphysical.

Wildfires are not caused by global warming

Scott at 02:48 AM on 31 July, 2023

Eclectic @14 /Bob Loblaw @13 You are correct, I assumed the diagram was from the IPCC, it isn't, and the increase it shows has very little to do with global warming. In that respect it is extremely misleading. The area burnt by wild fires has been decreasing not increasing. You criticised this conclusion as being from 2016 - yet in a 2020 blog post by the Royal Society the authors of the paper were interviewed again to find out whether things have changed since its publication. The answer was basically no. "... when considering the total area burned at the global level, we are still not seeing an overall increase, but rather a decline over the last decades. This has been confirmed in a series of subsequent studies, using data up to 2017 or 2018."
royalsociety.org/blog/2020/10/global-trends-wildfire/

From: 'Large Variations in Southern Hemisphere Biomass Burning During the Last 650 Years' Z. Wang,1 J. Chappellaz,2 K. Park,1 J. E. Mak1 (Science Vol 330 17 December 2010)

"These observations and isotope mass balance model results imply that large variations in the degree of biomass burning in the Southern Hemisphere occurred during the last 650 years, with a decrease by about 50% in the 1600s, an increase of about 100% by the late 1800s, and another decrease by about 70% from the late 1800s to present day."
Southern hemisphere biomass burning

[For some reason images are not showing in the preview but the source is correct]

The same picture is repeated globally. In 'Climate and human influences on global biomass burning over the past two millennia' by J. R. MARLON et al. (Nature Geoscience 1, 697–702; published online: 21 September 2008), they measure sedimentary charcoal records spanning six continents to document trends in both natural and anthropogenic biomass burning for the past two millennia. From this they obtain the following graph - again showing a very clear 20th century decline.

GlobalBiomassBurning

All this begs the question of why there has been such an increase in fires in California.
"Autumn and winter Santa Ana wind (SAW)–driven wildfires play a substantial role in area burned and societal losses in southern California. Temperature during the event and antecedent precipitation in the week or month prior play a minor role in determining area burned. "

"Models explained 40 to 50% of area burned, with number of ignitions being the strongest variable. One hundred percent of SAW fires were human caused, and in the past decade, powerline failures have been the dominant cause. Future fire losses can be reduced by greater emphasis on maintenance of utility lines and attention to planning urban growth in ways that reduce the potential for powerline ignitions."

See 'Ignitions explain more than temperature or precipitation in driving Santa Ana wind fires' by Jon E. Keeley et al. Science Advances 21 Jul 2021 Vol 7, Issue 30

In 'Nexus between wildfire, climate change and population growth in California' by Jon E. Keeley and Alexandra D. Syphard (Fremontia vol 47 Issue 2 2020) is a detailed analysis of wildfires in California. A distinction is drawn between fuel dominated and wind dominated fires.
FireCause

Population increase leading to urban expansion, accompanied by expansion of the electric power grid, increasing the chances of a powerline failure was a significant cause of wildfire. (The 2021 Dixie fire at 389,837 hectares was caused by a tree falling onto a powerline and could have been prevented had the power company acted promptly - see California Department of Forestry and Fire Protection, Investigation Report Case Number: 21CABTU009205-58). General poor maintenance by utilities has caused many wind dominated wildfires.

Fuel-dominated fires are mostly forest fires in lightly populated regions and so tend to result in less property damage. A century of fire suppression has led to a huge accumulation of fuel at ground level. As a result a low intensity surface fire can easily become a high intensity crown fire.

How 100 years of a misguided policy outlawing controlled burns has left California vulnerable to wild fires
www.theguardian.com/us-news/2019/nov/21/wildfire-prescribed-burns-california-native-americans

www.reuters.com/world/us/california-is-meant-burn-experts-teach-landowners-art-prescribed-burns-2023-06-01/

In conclusion, the total area burnt has been decreasing globally and in California where it has increased this is largely due to misguided policies of forest management and poorly maintained, overloaded power infrastructure. (Urban planning which doesn't adequately address fire hazard doesn't help either). I think linking wildfires to global warming is misguided and likely to backfire when it is revealled to be the least important factor.

2023 SkS Weekly Climate Change & Global Warming News Roundup #29

nigelj at 07:17 AM on 29 July, 2023

wilddouglascounty

"When the severity and frequency of extreme weather increases, the sea level rises and gets more acidic, wildlife populations move and wildfires abound, it is not because of Climate Change. It's because fossil fuel use that has changed the atmospheric and oceanic chemistry, allowing it to store more heat, changing the climate. Everyone who watches the weather needs to be reminded of that, too."

I'm sympathetic to what WDS wrote and what OPOF says. One reason. Apparently the link between fossil fuels and climate change is not mentioned in the IPCC summary for policy makers (or rarely mentioned I just forget which), because the oil exporting companies lobbied vigorously to keep it out. And in hindsight I've noticed our news media doesn't explicilty mention the link very often.

The counter argument is that almost everyone on the planet must know by now that fossil fuels are the main cause of climate change in recent decades. You would have to live a very isolated existence not to have heard by now.

But I think the link should always be mentioned more often and when appropriate. ( I hear what BL is saying) Reinforing the facts is arguably a good idea and cannot be a bad idea.

Wildfires are not caused by global warming

Eclectic at 05:57 AM on 26 July, 2023

Scott @12 , thank you for the link to the Royal Society research article (by Doerr & Santin) published in 2016. This was somewhat earlier than the disastrous wildfires recently in Australia and in California ~ disastrous not so much in their extent as in their effect on human lives & livelihoods.

Also earlier than the more recent ( non-Mediterranean ! ) wildfires in Canada that were "smoking out" regions of New England, into the bargain.

Also earlier than the [current] disastrous wildfires in southern Greece and Rhodes. (Difficult to picture a more Mediterranean scenario than southern Greece and Rhodes.) Human impact is a large factor in assessing the significance of fires ~ but I am sure the inhabitants & tourists in Rhodes are at present comforted by by the knowledge that the island of Rhodes is small in area, in global terms.

[IPCC] was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988 ... to provide policymakers with regular assessments on the current state of knowledge about climate change. [And was endorsed by the UN General Assembly in 1988.] So I suppose we can say that the IPCC is a political body in a sense . . . perhaps rivalling the well-known political nature of the WMO. Scott , you need to explain what you mean by the "political agenda" being "pushed" by all these international bodies. Are they in any way partisan or nefarious?

2023 SkS Weekly Climate Change & Global Warming News Roundup #29

Bob Loblaw at 05:10 AM on 26 July, 2023

Wild and One:

I'm going to have to express some disagreement. Although in public discourse and discussion there may be reasons to keep emphasizing the links between human activities, fossil fuels, and changing climates, in the scientific discussion (which Skeptical Science tries to focus on), the terms such as "climate change" have specific scientific meaning.

Not all climate change is induced by burning fossil fuels or other recent human activities. Using vocabulary that fails to recognize that will lead to a risk of losing credibility. Number 1 on the SkS "Most used climate myths" is "Climate's changed before". Number 89 is "They changed the name from 'global warming' to 'climate change'." Number 209 is "IPCC edited out natural causes of climate change".

It's unfortunate, but you need to be careful on how contrarians will twist your words.

Wildfires are not caused by global warming

Bob Loblaw at 04:55 AM on 26 July, 2023

Scott @ 12:

Frankly, you appear to be having some difficulty in reading comprehension. You make the serous accusation that "the IPCC is a political body with a political agenda to push", but you have very little in the way of logic or data to support that claim. Such an accusation flirts with the Comments Policy here, but let's entertain your case for a bit.

So,, you reference in your very first paragraph "the diagram from the IPCC". Can you be specific as to which diagram you are referring to? The original post references the IPCC just once, near the end, where is says:

...the latest IPCC report found in 2014 that “fire weather is projected to increase in most of southern Australia,” with days experiencing very high and extreme fire danger increasing 5–100% by 2050.

The first diagram in the post, in the tweet from Robert Rhode, has no citation, but states that the data are from the Australian Bureau of Meteorology. The graph is for Australia.

The second diagram is for California data. Again, the diagram is not attributed to a reference, but states "Data from Cal Fire", and is titled "California Wildfire Acres Burned".

The third diagram looks at the forest area burned in the western US. It is sourced from page 1105 in the referenced Fourth National Climate Assessment. The "national" part of that report title relates to its origin: the US Global Chance Research Program.

..and that is the last diagram in the post. So where is this "diagram from the IPCC"???

The original post also makes specific reference to Australia and California in its opening paragraph (the green box at the top). Under "heat worsens wildfires", the post specifically says (emphasis added):

In simple terms, vegetation and soil dry out, creating more fuel for fires to expand further and faster. This is particularly a problem in Mediterranean climates that are prone to drought, like in California and Australia.

So, the post is specifically looking at certain regions. What about the paper you link to? You make the claim:

Yet research published by the Royal Society shows the opposite...

Now, you do add "(globally)" after that. But why are you presenting this as if it evidence that goes again the evidence provided for Australia, California, and the western US? If we dig into that reference (which is now 7 years old), what we find is statements like the following, in their Synthesis and Conclusion:

We do not question that fire season length and area burned has increased in some regions over past decades, as documented for parts of North America, or that climate and land use change could lead to major shifts in future fire consequences, with potential increases in area burned, severity and impacts over large regions

That reference discusses many of the factors affected fire statistics, and make frequent reference to regional variations. (It also provides no new research - it is a review of existing research and expresses an opinion.)

And the figure you provide - which you introduce with "In particular in Europe..." is, as it says in the caption (which you included), for the European Mediterranean region.

So, your case seems to boil down to "but if we average out the areas where burning is less with the areas where burning is more, then the areas where burning is more won't be affected"??? Add in a bit of "but if there is not a trend in current data, there won't be a problem in the future", and you have someone that simply does not like the science. The OP and the references all indicate that increased risk of fire is something that is worth worrying about.

Wildfires are not caused by global warming

Scott at 00:16 AM on 26 July, 2023

Something is not adding up here. The diagram from the IPCC shows the area of wild fires increasing (for the Western US). Yet research published by the Royal Society shows the opposite (globally) and I give a link to the article:

doi.org/10.1098/rstb.2015.0345

"Analysis of charcoal records in sediments [31] and isotope-ratio records in ice cores [32] suggest that global biomass burning during the past century has been lower than at any time in the past 2000 years."

"The availability of satellite data now allows a more consistent evaluation of temporal patterns in area burned. Thus, from an analysis based on MODIS burned area maps between 1996 and 2012, Giglio et al. [35] present some rather notable outcomes. In contrast to what is widely perceived, the detected global area burned has actually decreased slightly over this period (by 1% yr−1). A more recent global analysis by van Lierop et al. [36], based primarily on nationally reported fire data supplemented by burned area estimates from satellite observations, shows an overall decline in global area burned of 2% yr−1 for the period 2003–2012."

In particular in Europe there has been a gradual declining trend in area burnt since 1980: Wildfire occurrence (a) and corresponding area burnt (b) in the European Mediterranean region for the period 1980–2010. Source: San-Miguel-Ayanz et al. [37].

Wildfire occurrence (a) and corresponding area burnt (b) in the European Mediterranean region for the period 1980–2010. Source: San-Miguel-Ayanz et al. [37].

Given that the concern should be for GLOBAL CO2 why is the emphasis on wild fires in the Western US? I'm beginning to suspect that the IPCC is a political body with a political agenda to push.

2023 SkS Weekly Climate Change & Global Warming News Roundup #29

wilddouglascounty at 15:01 PM on 24 July, 2023

The term "climate change" has buried the lead for too long, so it's time to correct this. When Sammy Sosa, Barry Bonds and Mark McGuire were not voted into the Baseball Hall of Fame, it was not because of Home Run Change, it was because of Performance Enhancing Drugs. And everyone who watches baseball knows that.

When the severity and frequency of extreme weather increases, the sea level rises and gets more acidic, wildlife populations move and wildfires abound, it is not because of Climate Change. It's because fossil fuel use that has changed the atmospheric and oceanic chemistry, allowing it to store more heat, changing the climate. Everyone who watches the weather needs to be reminded of that, too.

It's time to stop using euphemisms that don't explicitly connect the changing climate to fossil fuel use so that folks understand in the same way that folks understand the role of performance enhancing drugs in sports. Everyone needs to be reminded of the role fossil fuels has in climate change, just as they know about the role of performance enhancing drugs in turbocharging the natural talents of the users. Whenever discussing any of the things related to Climate Change we should make that link explicit by using phrases like:

- Fossil fuel induced Climate Change

- Increased greenhouse gases from Fossil Fuel use

- Climate Change caused by Fossil Fuel use

- Changed atmospheric chemistry through the widespread use of fossil fuels

and the like. And if someone says that you're politicizing the weather, tell them that this isn't just political; it's based on overwhelming scientific evidence. Refer them to the IPCC or skepticalscience websites if they are still deniers, and change the focus to how to become more energy efficient first, replace fossil fuel use with renewables second, and nurture local ecosystems third. We don't have a choice but to make things super-clear if we are to have a chance to turn the ship away from almost unimaginable disasters for future generations.

How big is the “carbon fertilization effect”?

daveburton at 01:45 AM on 14 July, 2023

Eclectic wrote, "Daveburton @22 ~ Please explain more of your first chart [ IPCC's decadal Carbon Flux Comparison 1980-2019 ]. The natural sink flux figures… show a rather steady proportionality to the total carbon emissions."

Glad to. Any two things which steadily increase are thereby correlated. There's only a possibility that the relationship might be causal if there's a possible mechanism for such causality.

There's no possible mechanism by which the rate at which CO2 emerges from chimneys could govern the rate at which CO2 is taken up by trees & absorbed by the oceans, or vice-versa, so the relationship cannot be causal — just as this famous relationship is not causal:

does cheese consumption cause death by bedsheet entanglement?

Eclectic wrote, "The land sink shows about 30-35% of total emissions, while the sum of land & ocean remains around 55-60%."

Yes, I usually say "about half," as in, "If our CO2 emissions were cut by more than about half then the atmospheric CO2 level would be falling, rather than rising."

It is important to recognize that the relationship is merely coincidental, not causal.

Eclectic wrote, "as the decades progress, the natural carbon sink flux in absolute terms rises with the rising emissions ~ but does not show a proportional increase."

The rate at which natural processes, such as ocean uptake, uptake by trees and soil ("greening"), and rock weathering, remove CO2 from the air, is affected in minor ways by many factors, but in a major way by only one: the current amount of CO2 in the air.

Our CO2 emission rate does not and cannot affect the natural removal rate, except indirectly, in the long term, by being one of the most important factors which affect the amount of CO2 in the air.

Eclectic wrote, "looking back in time ~ as the atmospheric CO2 level decreases, the size of the natural sink flux decreases also."

That is correct. It will also be correct looking forward in time, when CO2 levels are falling, someday.

Eclectic wrote, "this directly contradicts your hypothesis of 'if emissions were halved ... atmospheric CO2 level would plateau.'"

If you'll allow me to use "halved" as a shorthand for "reduced to the point at which emissions merely equal current natural removals, rather than exceed them," then those two statements are both correct, and perfectly consistent. It's pCO2 (level), not the rate of CO2 emissions, which (mostly) governs the rates of all the natural CO2 removal from the atmosphere.

Of course there are also minor factors which affect the removal rates. For instance, as we've already discussed, a 1°C rise in water temperature slows ocean uptake of CO2 by roughly 3%. Conversely, a rise in air temperature accelerates CO2 removal by rock weathering. (Sorry, I don't have a quantification of that.) But the main factor which controls the rate of CO2 removals is pCO2.

Eclectic wrote, "While the nutritive components of some food crops may reduce slightly as CO2 rises…"

Oh boy, another rabbit hole! That's the Loladze/Myers "nutrition scare."

It is of little consequence. That should be obvious if you consider that crops grown in commercial greenhouses with CO2 levels as high as 1500 ppmv are as nutritious as crops grown outdoors with only 30% as much CO2.

≥1500 ppmv CO2 is optimal for most crops. That's why commercial greenhouses typically use CO2 generators to raise daytime CO2 concentration to well above 1000 ppmv. It is expensive, but they go to that expense because elevated CO2 (eCO2) makes crops much healthier and more productive. (They don't typically supplement CO2 at night unless using grow-lamps, because plants can't use the extra CO2 without light.)

If elevating CO2 by >1000 ppmv doesn't cause crops to be less nutritious, then elevating CO2 by only 140 ppmv obviously doesn't, either.

Better crops yields, due to eCO2 or any other reason, can cause lower levels (but not lower total amounts) of nutrients which are in short supply in the soil. But that doesn't happen to a significant extent when agricultural best practices are employed.

I had an impromptu online debate about the nutrition scare with its most prominent promoter, mathematician Irakli Loladze, in the comments on a Quora answer. If you're not a Quora member you can't read it there, so I saved a copy here. He acknowledged to me that food grown in greenhouses at elevated CO2 levels is as nutritious as food grown outdoors.

Faster-growing, more productive crops require more nutrients per acre, but not more nutrients per unit of production.

Inadequate nitrogen fertilization reduces protein production relative to carbohydrate production, because proteins contain nitrogen, but carbohydrates don't. Likewise, low levels of iron or zinc in soils cause lower levels of those minerals in some crops. So, it is possible, by flouting well-established best agricultural practices, to contrive circumstances under which eCO2, or anything else which improves crop yields, causes reduced levels of protein or micronutrients in crops.

But farmers know that the more productive crops are, the more nutrients they need, per acre. Competent farmers fertilize accordingly.

Or, for nitrogen, they may plant nitrogen-fixing legumes — which benefit greatly from extra CO2.

If you don’t fertilize according to the needs of your crops, negative consequences may include reductions in protein and/or micronutrient levels in the resulting crops. The cause of such reductions isn't eCO2s, it's poor agricultural practices.

The nutrient scare is an attempt to put a negative "spin" on the most important benefit of eCO2: that it improves crop yields.

Eclectic wrote, "it is (as you state) beyond argument that higher CO2 benefits overall crop yield & plant mass."

That's correct. Moreover, agronomy studies show that for most crops the effect is highly linear as CO2 levels rise, until above about 1000 ppmv (which is far higher than we could ever hope to drive outdoor CO2 levels by burning fossil fuels). That linearity is obvious in the green (C3) trace, here:

CO2 vs plant growth, C3 & C4

That improvement is one of several major reasons that catastropic famines are fading from living memory.

If you're too young to remember huge, catastrophic famines, count yourself blessed. Through all of human history, until very recently, famine was one of the great scourges of mankind, the "Third Horseman of the Apocalypse." But no more. This is a miracle!

https://ourworldindata.org/famines

Ending famine is a VERY Big Deal, comparable to ending war and disease. Compare:

● Covid-19 killed 0.1% of world population.
● 1918 flu pandemic killed about 2%.
● WWII killed 2.7%.
● The near-global drought and famine of 1876-78 killed about 3.7% of the world population.

Eclectic wrote, "other CO2/AGW concomitant effects of increased droughts /floods /heat-waves can be harmful to crop yields in open-field agriculture. [And especially so for the staple crop of maize.]"

Well, let's examine those one at a time.

Heat-waves. Overall, temperature extremes are not worsened by the warming trend. Heat waves are slightly worsened, but by less than cold snaps are mitigated. That's because, thanks to "Arctic amplification," warming is disproportionately at chilly high latitudes, and it is greatest at night and in winter. The tropics warm less, which is nice, because they're warm enough already.

1°C is about the temperature change you get from a 500 foot elevation change. (That's calculated from an average lapse rate of 6.5 °C/km.)

On average, 1°C is similar in effect to a latitude change of about sixty miles, as you can see by looking at an agricultural growing zone map. Here's one, from the Arbor Day Foundation:

From eyeballing the map, you can see that 1°C (1.8°F) = about 50-70 miles latitude change.

James Hansen and his colleagues reported a similar figure: "A warming of 0.5°C... implies typically a poleward shift of isotherms by 50 to 75 km..."

1°C is less than the hysteresis ("dead zone") in your home thermostat, which is the amount that your indoor temperatures go up and down, all day long, without you even noticing.

In the American Midwest, farmers can fully compensate for 1°C of climate change by adjusting planting dates by about six days.
Des Moines temperature by month

Floods. Theoretically, by accelerating the water cycle, climate change could increase the frequency or severity of floods. But the effect is too slight to be noticeable. AR6 says no change in global flood frequency is detectable:

AR6 on floods

Droughts. Droughts have not worsened. In fact, the global drought trend is slightly down. Here's a study:

Hao et al. (2014). Global integrated drought monitoring and prediction system. Sci Data 1(140001). doi:10.1038/sdata.2014.1

Here's the U.S. drought trend (the bottom/orange side of the graph):
https://www.ncei.noaa.gov/access/monitoring/uspa/wet-dry/0

U.S. very wet and very dry

Not only does climate change not worsen droughts, it has long been settled science that eCO2 improves plants' water use efficiency (WUE) and drought resilience, by improving CO2 stomatal conductance relative to transpiration. So eCO2 is especially beneficial in arid regions, and for crops which are under drought stress.

Maize (corn) has been very heavily studied. Even though it is a C4 grass, it benefits greatly from elevated CO2, especially under drought stress. Here's a study (one of many):

Chun et al. (2011). Effect of elevated carbon dioxide and water stress on gas exchange and water use efficiency in corn. Agric For Meteorol 151(3), pp 378-384, ISSN 0168-1923. doi:10.1016/j.agrformet.2010.11.015.

EXCERPT:
"There have been many studies on the interaction of CO2 and water on plant growth. Under elevated CO2, less water is used to produce each unit of dry matter by reducing stomatal conductance."

Here's a similar study about wheat:

Fitzgerald GJ, et al. (2016) Elevated atmospheric [CO2] can dramatically increase wheat yields in semi-arid environments and buffer against heat waves. Glob Chang Biol. 22(6):2269-84. doi:10.1111/gcb.13263.

However, I agree with you that putting a monetary value on the benefits of CO2 for crops is difficult. In part that's because the price of food soars when it's in short supply, and plummets when it's plentiful. So, for example, if we were to attribute, say, 15% of current crop yields to CO2 fertilization & CO2 drought mitigation, and value that 15% using current crop prices, we would be underestimating the true value, because absent that 15% boost the prices would have been much higher.

How big is the “carbon fertilization effect”?

Eclectic at 21:26 PM on 13 July, 2023

Daveburton @22 ~ Please explain more of your first chart [ IPCC's decadal Carbon Flux Comparison 1980-2019 ].

The natural sink flux figures there are indeed broad brush, to be sure ~ but they show a rather steady proportionality to the total carbon emissions. # The land sink shows about 30-35% of total emissions, while the sum of land & ocean remains around 55-60% . It may not be statistically significant ~ but the proportion actually reduces as the emissions increase over the last 3 decades.

In other words, as the decades progress, the natural carbon sink flux in absolute terms rises with the rising emissions ~ but does not show a proportional increase.

The corollary of that is: looking back in time ~ as the atmospheric CO2 level decreases, the size of the natural sink flux decreases also. Daveburton, this directly contradicts your hypothesis of "if emissions were halved ... atmospheric CO2 level would plateau."

[B] Papers such as Zhu et al. 2016 [Nature Climate Change] and the Charles Taylor & Wolfram Schlenker one (not peer-reviewed) you mention above . . . point out the multifactorial complexities in assessing the relevance of greening & browning (of vegetated land) where measured by Leaf Area Index (seen per satellite). Very difficult to come to a substantive conclusion of value ! While the nutritive components of some food crops may reduce slightly as CO2 rises . . . nevertheless, it is (as you state) beyond argument that higher CO2 benefits overall crop yield & plant mass.

However, Daveburton ~ and I presume that this has been pointed out to you many times before ~ the other CO2/AGW concomitant effects of increased droughts /floods /heat-waves can be harmful to crop yields in open-field agriculture. [And especially so for the staple crop of maize.]

How big is the “carbon fertilization effect”?

daveburton at 15:36 PM on 13 July, 2023

Rob wrote elsewhere, "greening is now turning into 'browning.' ... fertilization [has now been] overwhelmed by other effects... In other words, the greening has now stopped," and here, "You were making the claim that natural sinks were removing more of our emissions, and that is not the case by any stretch of the imagination.""

Here's AR6 WG1 Table 5.1, which shows how natural CO2 removals are accelerating:
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter_05.pdf#page=48

Here it is with the relevant bits highlighted:
https://sealevel.info/AR6_WG1_Table_5.1.png
Or, more concisely:
https://sealevel.info/AR6_WG1_Table_5.1_annot1_partial_carbon_flux_comparison_760x398.png
Excerpt from AR6 WG1 Table 5.1, showing how natural removals of carbon from the atmosphere are accelerating
(Note: 1 PgC = 0.46962 ppmv = 3.66419 Gt CO2.)

As you can see, as atmospheric CO2 levels have risen, the natural CO2 removal rate has sharply accelerated. (That's a strong negative/stabilizing climate feedback.)

AR6 FAQ 5.1 also shows how both terrestrial and marine carbon sinks have accelerated, here:
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter05.pdf#page=99

Here's the key graph; I added the orange box, to highlight the (small) portion of the graph which supports your contention that, "greening is now turning into 'browning.' ... fertilization [has now been] overwhelmed by other effects... In other words, the greening has now stopped."

https://sealevel.info/AR6_FAQ_5p1_Fig_1b_final2.png

Here's the caption, explicitly saying that natural removal of carbon from the atmosphere is NOT weakening:

The authors did PREDICT a "decline" in the FUTURE, "if" emissions "continue to increase." But it hasn't happened yet.

What's more, the "decline" which they predicted was NOT for the rate of natural CO2 removals by greening and marine sinks, anyhow. Rather, if you read it carefully, you'll see that that hypothetical decline was predicted for the ratio of natural removals to emissions.

What's more, their prediction is conditional, depending on what happens with future emissions ("if CO2 emissions continue to increase").

Well, predictions are cheap. My prediction is that natural removals of CO2 from the atmosphere will continue to accelerate, for as long as CO2 levels rise.

The "fraction" which they predict might decline, someday, doesn't represent anything physical, anyhow. (It is one minus the equally unphysical "airborne fraction.") Our emission rate is currently about twice the natural removal rate, so if emissions were halved, the removal "fraction" would be 100%, and the atmospheric CO2 level would plateau. If emissions were cut by more than half then the removal "fraction" would be more than 100%, and the CO2 level would be falling.

I wrote elsewhere, "This recent study quantifies the effect for several major crops. Their results are toward the high end, but their qualitative conclusion is consistent with many, many other studies. They reported, "We consistently find a large CO2 fertilization effect: a 1 ppm increase in CO2 equates to a 0.4%, 0.6%, 1% yield increase for corn, soybeans, and wheat, respectively.""

If you recall that mankind has raised the average atmospheric CO2 level by 140 ppmv, you'll recognize that those crop yield improvements are enormous!

Rob replied, "If you actually read more than just the abstract of that study you find this on page 3: 'Complicating matters further, a decline in the global carbon fertilization effect over time has been documented, likely attributable to changes in nutrient and water availability (Wang et al. 2020).'"

Rob, I already addressed Wang et al (2020), but you might not have seen it, because the mods deemed it off-topic and deleted it. Here's what I wrote:

Rob, it's possible that your confusion on the greening/browning point was due to a widely publicized paper, with an unfortunately misleading title:

Wang et al (2020), "Recent global decline of CO2 fertilization effects on vegetation photosynthesis." Science, 11 Dec 2020, Vol 370, Issue 6522, pp. 1295-1300, doi:10.1126/science.abb7772

Many people were misled by it. You can be forgiven for thinking, based on that title, that greening due to CO2 fertilization had peaked, and is now declining.

But that's not what it meant. What it actually meant was that the rate at which plants remove CO2 from the atmosphere has continued to accelerate, but that its recent acceleration was less than expected. (You can't glean that fact from the abstract; would you like me to email you a copy of the paper?)

What's more, if you read the "Comment on" papers responding to Wang, you'll learn that even that conclusion was dubious:

Sang et al (2021), "Comment on 'Recent global decline of CO2 fertilization effects on vegetation photosynthesis'." Science 373, eabg4420. doi:10.1126/science.abg4420

Frankenberg et al (2021), "Comment on 'Recent global decline of CO2 fertilization effects on vegetation photosynthesis'." Science 373, eabg2947. doi:10.1126/science.abg2947

Agronomists have studied every important crop, and they all benefit from elevated CO2, and experiments show that the benefits continue to increase as CO2 levels rise to far above what we could ever hope to reach outdoors. Perhaps surprisingly, even the most important C4 crops, corn (maize) and sugarcane, benefit dramatically from additional CO2. C3 plants (including most crops, and all carbon-sequestering trees) benefit even more.

Rob also quoted the study saying, "While CO2 enrichment experiments have generated important insights into the physiological channels of the fertilization effect and its environmental interactions, they are limited in the extent to which they reflect real-world growing conditions in commercial farms across a large geographic scale."

That's a reference to the well-known fact that Free Air Carbon Enrichment (FACE) studies are less accurate than greenhouse and OTC (open top container) studies, because in FACE studies wind fluctuations unavoidably cause unnaturally rapid variations in CO2 levels. So FACE studies consistently underestimate the benefits of elevated CO2. Here's a paper about that:

Bunce, J.A. (2012). Responses of cotton and wheat photosynthesis and growth to cyclic variation in carbon dioxide concentration. Photosynthetica 50, 395–400. doi:10.1007/s11099-012-0041-7

The issue is also explained by Prof. George Hendrey, here:

"Plant responses to CO2 enrichment: Much of what is known about global ecosystem responses to future increases in atmospheric CO2 has been gained through Free-Air CO2 Enrichment (FACE) experiments of my design. All FACE experiments exhibit rapid variations in CO2 concentrations on the order of seconds to minutes. I have shown that long-term photosynthesis can be reduced as a consequence of this variability. Because of this, all FACE experiments tend to underestimate ecosystem net primary production (NPP) associated with a presumed increased concentration of CO2."

Rob wrote, "It does seem that you're claiming CO2 uptake falls with increasing temperature.""

That is correct for uptake by water. Or, rather, it would be correct, were it not for the fact that the small reduction in CO2 uptake due to the temperature dependence of Henry's Law is dwarfed by the large increase in CO2 uptake due to the increase in pCO2.

Rob wrote, "But it's unclear to me how you think this plays into the conclusion that CO2 levels would 'quickly normalize' over the course of 35 years" and also, "You also claimed CO2 concentrations would quickly come down (normalize) once we stop emitting it. This is also not correct unless you're using 'normalize' to mean 'stabilize at a new higher level'."

Perhaps you've confused me with someone else. I said nothing about CO2 levels "normalizing."

I did point out that the effective half-life for additional CO2 which we add to the atmosphere is only about 35 years. I wrote:

The commonly heard claim that "the change in CO2 concentration will persist for centuries and millennia to come" is based on the "long tail" of a hypothetical CO2 concentration decay curve, for a scenario in which anthropogenic CO2 emissions go to zero, CO2 level drops toward 300 ppmv, and carbon begins slowly migrating back out of the deep oceans and terrestrial biosphere into the atmosphere. It's true in the sense that if CO2 emissions were to cease, it would be millennia before the CO2 level would drop below 300 ppmv. But the first half-life for the modeled CO2 level decay curve is only about 35 years, corresponding to an e-folding "adjustment time" of about fifty years. That's the "effective atmospheric lifetime" of our current CO2 emissions.

Rob wrote, "Dave... The fundamental fact that you disputed is that oceans take up about half of our emissions."

That reflects two points of confusion, Rob.

In the first place, our emissions are currently around 11 PgC/year (per the GCP). The oceans remove CO2 from the atmosphere at a current rate of a little over 2.5 PgC/year. That's only about 1/4 of the rate of our emissions, not half.

More fundamentally, the oceans are not removing some fixed fraction of our emissions. None of the natural CO2 removal processes do. All of them remove CO2 from the bulk atmosphere, at rates which largely depend on the atmospheric CO2 concentration, not on our emission rate. If we halved our CO2 emission rate, natural CO2 removals would continue at their current rate.

Because human CO2 emissions are currently faster than natural CO2 removals, we've increased the atmospheric CO2 level by about 50% (140 ppmv), but we've increased the amount of carbon in the oceans by less than 0.5%, as you can see in AR5 WG1 Fig. 6-1.

Sorry, this got kind of long. I hope I addressed all your concerns.

How big is the “carbon fertilization effect”?

Rob Honeycutt at 11:17 AM on 11 July, 2023

Dave... Your reference to the inset on FAQ 5.1 is comical at best.

It states exactly what I'm telling you, as did the other bits I posted.

FAQ 5.1: Is natural removal of carbon
from the atmosphere weakening?
No, natural carbon sinks have taken up a near constant fraction of our carbon dioxide (CO2) emissions over the last six decades.

You were making the claim that natural sinks were removing more of our emissions, and that is not the case by any stretch of the imagination. And the caption you posted goes on to say...

However, this fraction is expected to decline in the future if CO2 emissions continue to increase.

How can you not understand this? Take note that AR6, though it's the most current IPCC report, came out nearly two years ago, and the report is relying on data and research that was completed well before even that.

The most recent papers are saying that, yes, that CO2 fertilization effect is now waning.

High economic costs of reduced carbon sinks and declining biome stability in Central American forests

Rising Temperatures Can Negate CO2 Fertilization Effects on Global Staple Crop Yields: A Meta-Regression Analysis

Tropical Forests’ Carbon Sink Is Rapidly Weakening – Crucial for Stabilizing Earth’s Climate

Once again, in your own citation the language is clear.

FAQ 5.1 | Is the Natural Removal of Carbon From the Atmosphere Weakening?
For decades, about half of the carbon dioxide (CO2) that human activities have emitted to the atmosphere has been taken up by natural carbon sinks in vegetation, soils and oceans. These natural sinks of CO2 have thus roughly halved the rate at which atmospheric CO2 concentrations have increased, and therefore slowed down global warming. However, observations show that the processes underlying this uptake are beginning to respond to increasing CO2 in the atmosphere and climate change in a way that will weaken nature’s capacity to take up CO2 in the future. Understanding of the magnitude of this change is essential for projecting how the climate system will respond to future emissions and emissions reduction efforts.

The "observations show" means they are already seeing this happening, and that is based on research that's at least half a decade old.

Hansen predicted the West Side Highway would be underwater

daveburton at 06:58 AM on 11 July, 2023

Philippe Chantreau wrote, "I will respond to Dave Burton on the CO2 fertilization thread on the part of this latest post regarding that subject."

Will you please provide a link to your comment to me, Philippe?

[Major snip]

Rob Honeycutt wrote, "1) That is not an image that appears in AR6, not with the added orange box. Thus you're co-opting their work to infer conclusions they do not make."

That's incorrect.

Since we're onto the next page of comments now, here's the image again:
https://sealevel.info/AR6_FAQ_5p1_Fig_1b_final2.png

If you enlarge it you can see, in fine print, the URL that will take you to where you can find it in chapter 5 of AR6:
https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter05.pdf#page=99

I added the orange box to highlight the (small) part of the image which supports your contention that, "greening is now turning into 'browning.' ... fertilization [has now been] overwhelmed by other effects... In other words, the greening has now stopped."

AR6 directly contradicts your contention, Rob. In fact, it does so in the caption on that very figure:

They could not have been clearer in stating that natural removal of carbon from the atmosphere is NOT weakening.

The authors did PREDICT a "decline" in the FUTURE, "if" emissions "continue to increase." But that hasn't happened yet, and the "decline" which they predicted was NOT for the rate of natural CO2 removals by greening and marine sinks, anyhow. Rather, that hypothetical decline was predicted for the ratio of natural removals to emissions, and their prediction is conditional, depending on what happens with future emissions ("if CO2 emissions continue to increase").

Well, predictions are cheap. My prediction is that natural removals of CO2 from the atmosphere will continue to accelerate, for as long as CO2 levels rise.

Rob, it's possible that your confusion on the greening/browning point was due to a widely publicized paper, with an unfortunately misleading title:

Wang et al (2020), "Recent global decline of CO2 fertilization effects on vegetation photosynthesis." Science, 11 Dec 2020, Vol 370, Issue 6522, pp. 1295-1300, doi:10.1126/science.abb7772

Many people were misled by it. You can be forgiven for thinking, based on that title, that greening due to CO2 fertilization had peaked, and is now declining.

What's more, if you read the "Comment on" papers responding to Wang, you'll learn that even that conclusion was very dubious:

Sang et al (2021), "Comment on 'Recent global decline of CO2 fertilization effects on vegetation photosynthesis'." Science 373, eabg4420. doi:10.1126/science.abg4420

Frankenberg et al (2021), "Comment on 'Recent global decline of CO2 fertilization effects on vegetation photosynthesis'." Science 373, eabg2947. doi:10.1126/science.abg2947

Bob Loblaw wrote, "...I have no way of knowing whether our daveburton is the same Dave Burton seen in the discussions at Tamino's... The other Dave Burton's name shows up quite a few times, although he does not comment."

Yes, I'm the Dave Burton who Tamino intermittently criticizes. Unfortunately, when I try to comment on his blog, he nearly always deletes my comments, so I stopped trying. Suffice to say, if you like being misled, you should enjoy his blog. (Example.)

Hansen predicted the West Side Highway would be underwater

daveburton at 03:51 AM on 6 July, 2023

Thanks for fixing those links, Rob. We were obviously typing simultaneously; you beat me to it by 7 minutes.

However, nothing I wrote was misleading. If you "follow the link to the actual IPCC page to read the full" table, you'll see that it shows exactly what I said it shows: as atmospheric CO2 levels have risen, the natural CO2 removal rate has sharply accelerated. (That's a strong negative/stabilizing climate feedback.)

The commonly heard claim that "the change in CO2 concentration will persist for centuries and millennia to come" is based on the "long tail" of a hypothetical CO2 concentration decay curve, for a scenario in which anthropogenic CO2 emissions go to zero, CO2 level drops toward 300 ppmv, and carbon begins slowly migrating back out of the deep oceans and terrestrial biosphere into the atmosphere. It's true in the sense that if CO2 emissions were to cease, it would be millenia before the CO2 level would drop below 300 ppmv. But the first half-life for the modeled CO2 level decay curve is only about 35 years, corresponding to an e-folding "adjustment time" of about fifty years. That's the "effective atmospheric lifetime" of our current CO2 emissions.

Moreover, it is not correct to say that "the ocean takes up about half of our emissions." Our emissions are currently around 11 PgC/year (per the GCP). The oceans remove CO2 from the atmosphere at a current rate of a little over 2.5 PgC/year, but they are not removing some fixed fraction of our emissions. If we halved our emission rate, natural CO2 removals would continue at their current rate.

In the oceans, biology generally trumps chemistry, and that is certainly true for CO2 uptake. Some people think that the capacity of the oceans to take up CO2 is limited to surface water by ocean stratification. But that's incorrect, beause the "biological carbon pump" rapidly moves CO2 from surface waters into the ocean depths, in the form of "marine snow."

The higher CO2 levels go, the faster that "pump" works. Here's a paper about it:
https://www.science.org/doi/reader/10.1126/science.aaa8026

Once carbon has migrated from the ocean surface to the depths, most of it remains sequestered for a very long time. Some of it settles on the ocean floor, but even dissolved carbon is sequestered for a long time. For instance, it is estimated that the AMOC takes about 1000 years to move carbon-rich water from high latitudes to the tropics, where it can reemerge. That is obviously far longer than the anthropogenic CO2 emission spike will last.

Hansen predicted the West Side Highway would be underwater

daveburton at 01:37 AM on 6 July, 2023

Sorry, I didn't realize that bare URLs don't automatically get recognized and turned into links.

Here's AR6 WG1 Table 5.1, which shows how natural CO2 removals are accelerating:
LINK

Here it is with the relevant bits highlighted:
https://sealevel.info/AR6_WG1_Table_5.1.png
Or, more concisely:
LINK
Excerpt from AR6 WG1 Table 5.1, showing how natural removals of carbon from the atmosphere are accelerating
(Note: 1 PgC = 0.46962 ppmv = 3.66419 Gt CO2.)

Here are the best long U.S. Atlantic and Pacific sea-level measurement records, respectively, with linear and quadratic regressions calculated for the last 100 years (based on monthly mean sea level data from 1923/6 through 2023/5):

https://sealevel.info/MSL_graph.php?id=Battery&c_date=1923/6-2023/5
Sea-level vs CO2 at the Battery, NYC, last 100 years
linear trend = 3.293 ±0.163 mm/yr
acceleration = 0.00641 ±0.01258 mm/yr²

https://sealevel.info/MSL_graph.php?id=Honolulu&c_date=1923/6-2023/5
Sea-level vs CO2 at Honolulu, last 100 years
linear trend = 1.534 ±0.236 mm/yr
acceleration = 0.00568 ±0.01825 mm/yr²

Hansen predicted the West Side Highway would be underwater

Rob Honeycutt at 01:30 AM on 6 July, 2023

Dave... So much is wrong in that post. Let's just start with atmospheric CO2 perturbation. No one claims it stays up there forever. But the change in CO2 concentration will persist for centuries and millennia to come.

https://climatehomes.unibe.ch/~joos/papers/joos97eps.pdf

Your sealevel.info snippet is misleading, and I assume you understand that virtually no one is going to follow the link to the actual IPCC page to read the full passage, because it will directly contradict what you're saying.

What you're looking at in those changes is a function of partial pressure. The ocean takes up about half of our emissions (lucky for those of us who live in the atmosphere, not so lucky for sea dwelling creatures). The increases you're demonstrating are merely a function of increased atmospheric concentrations. The oceans, in particular, are not going to continue to take up CO2 beyond what it's capable of doing due to partial pressure.

https://www.pmel.noaa.gov/co2/story/Ocean+Carbon+Uptake

97% consensus on human-caused global warming has been disproven

michael sweet at 11:47 AM on 5 July, 2023

Duran3d:

As has been pointed out, a consensus is a supermajority of those consulted. For IPCC reports they usually state what the consensus is for the least amount of harm from the discussed issue. For example, the IPCC sea level rise projections are set at what a consensus thinks are the minimum rise expected. That means that a large majority of scientists who study sea level rise think sea level rise will be greater than the IPCC consensus. Trying to minimize something that has already been minimized is not a consistant argument.

Claiming that it must be a unanimous consensus will not get you any traction here at Skeptical Science.

Wildfires are not caused by global warming

One Planet Only Forever at 07:46 AM on 2 July, 2023

PollutionMonster @9,

Regarding 'attribution of Canada's current wildfires to human caused climate change', the following Carbon Brief article may help you: "Media reaction: Canada’s wildfires in 2023 and the role of climate change"

The article states that:

"No attribution studies have so far made a climate connection with the ongoing wildfires in Canada.

But previous studies have looked at the link between climate change and other extreme weather events. One study found that climate change made a 2020 Siberian heatwave at least 600 times more likely. This heat broke temperature records and led to wildfires.

Additionally, the IPCC said that wildland fire has been “identified as a top climate-change risk facing Canada”.

The interactive map below displays a 2020 review of scientific studies finding that climate change is increasing the risk of wildfires globally."

The bolded words in the quote are links to additional information in the article. Read the article to access those links. And read the entire article. It includes additional information you may find helpful in your attempts to help others learn to better understand this issue.

Greenhouse effect has been falsified

EddieEvans at 23:53 PM on 26 June, 2023

Has the greenhouse effect been falsified?

Robotic Reading: Has the greenhouse effect been falsified?

While Earth’s climate has changed throughout its history, the current warming is happening at a rate not seen in the past 10,000 years.

According to the Intergovernmental Panel on Climate Change (IPCC), "Since systematic scientific assessments began in the 1970s, the influence of human activity on the warming of the climate system has evolved from theory to established fact."1

Scientific information taken from natural sources (such as ice cores, rocks, and tree rings) and from modern equipment (like satellites and instruments) all show the signs of a changing climate.

From global temperature rise to melting ice sheets, the evidence of a warming planet abounds.

Greenhouse effect has been falsified

EddieEvans at 23:50 PM on 26 June, 2023

"Has the greenhouse effect been falsified?" with current NASA evidence for anthropogenic greenhouse gas warmoing.

EVIDENCE

How Do We Know Climate Change Is Real?

There is unequivocal evidence that Earth is warming at an unprecedented rate. Human activity is the principal cause.

While Earth’s climate has changed throughout its history, the current warming is happening at a rate not seen in the past 10,000 years.

Scientific information taken from natural sources (such as ice cores, rocks, and tree rings) and from modern equipment (like satellites and instruments) all show the signs of a changing climate.

From global temperature rise to melting ice sheets, the evidence of a warming planet abounds.

2nd law of thermodynamics contradicts greenhouse theory

scaddenp at 11:28 AM on 13 June, 2023

RH - well CO2"Science" have long history in misrepresenting what science papers actually say, secure in the knowledge that their intended audience won't read them to check. LikeitWarm, I agree that the Idso's are intelligent and smart - just not in a good way.

Likeitwarm - I appreciate that it is very difficult to evaluate material that you dont know very well. However, a common strategy for the deniers is the"strawman fallacy". Ie they claim that "science says X", which means that it follows that Y should be observed. If Y is not observed, then clearly X is wrong. (eg Idso is effectively claiming "Science says CO2 is only thing that effects temperature, therefore past temperatures must reflect CO2 concentration" ). If you discover that science says no such thing (eg check with what the IPCC reports claim instead) and that your source would likely be aware of that, (eg quoting or misquoting IPCC) then you have reasonable grounds for assuming that the source is bad actor, and not to be compared with what peer-reviewed science is saying (no matter how appealing their presentation is).

At a glance - How reliable are climate models?

nigelj at 17:19 PM on 31 May, 2023

Gordon @10

The IPCC WR5 projection in your comments includes observational data from 1970 - 2012 only. Its old data possibly from an older IPCC report. The observational data is quite close to the modelling for much of that period but the years 2005 - 2012 (approx) in that graph clearly fall significantly below the modelling mid line prediction. But this is a relatively short time frame, and it represents short term natural variation that models can't fully predict in terms of timing. This is the alleged pause in surface temperatures, which amounted to a flat period in the warming trend of about 7 years and was due to the influence of natural variation ( in simple terms)

The graph posted by Bob Loblow @ 8 includes observational data from 1970 - 2022 and so its much wider and more recent data, and its obvious that the warming trend from 2012 - 2022 has swung back to near the model mid line prediction, and that the observational trend is tracking quite close to the modelling overall for the full period 1920 - 2022. The modelling is obviously not running significantly hot.

I'm surprsied you didn't notice any of this.

At a glance - How reliable are climate models?

Gordon at 14:45 PM on 31 May, 2023

Bob @ 6

Why does the IPCC run a similar chart in AR5 ?

10 year anniversary of 97% consensus study

michael sweet at 02:54 AM on 26 May, 2023

John Kerry was quoted addressing the British Parliment as saying:

"“If you have five tipping points, and two of them involve the potential of metres, literally multiple metres, double digits of sea level rise, that’s as good a definition of catastrophe as you can achieve.

“And the reality is that that is where we are headed unless we do more about it. Now, why do I have this measure of optimism and of our capacity? Because it is within our capacity."

I thnk in addition to multiple meters of sea level rise there are other potential consequences of climate chnge that would qualify as "catastrophic". Perhaps we could make a list.

I saw a projection of a billion climate refugees or more under some conditions. For me that is way past catastrophic.

How many human deaths in one year , or cumulative, before it counts as catastrophic? Only one if it is a close friend or relative.

What conditions do others here think would count as catastrophic. Perhaps we could find a consensus, Undoubtedly we all have different conditions that have to be met for the problem to be catastrophic.

I remember when the IPCC AR5 came out in 2014 with a list of severe consequences. I wondered at the time if I would live to see sea level rise causing damage, widespread fire storms, heat conditions killing millions etc. I was 56 at the time and thought I would live another 30 years. Now, only 8 years later, we see these problems already happening around the world. I can only imagine what it would be like in 2100 if we do not take as strong action as possible immediately.

In my experience, persons who ask for definations of catastrophic want to minimize the actions we take to try to avoid the already begun catastrophic climate change.

10 year anniversary of 97% consensus study

Gordon at 09:01 AM on 17 May, 2023

Bob @12 & 13,

I would prefer to refer to the Skeptical Science definition of catastrophic, that being a the environmental effect of a greater than 4°C temperature rise. We could also ask Dana Nuccitelli (a regular cotributor here) what his definition was when he wrote:

Climate contrarians will often mock 'CAGW' (catastrophic anthropogenic global warming), but the sad reality is that CAGW is looking more and more likely every day.

(Eclectic, is Dana just shouting a slogan here ?)

My original question was what percentage of climate scientists today believe that global warming will be catastrophic ? Given that the IPCC now believes that RCP8.5 has a low likelyhood of occuring, the chances of a greater than 4°C warming along with the prophesied catastrophic effects seem unsupported.

CO2 is not the only driver of climate

Bob Loblaw at 08:12 AM on 9 May, 2023

Another source of temperature reconstructions is the IPCC sixth assessment report. The following figure is from the Summary For Policy Makers. Full scale image is available at this link. The grey shading represents the uncertainty. Nothing even comes close to piotr's claim of a "decrease up to 1.5°C".

Temperature reconstructions

At a glance - The greenhouse effect and the 2nd law of thermodynamics

Bob Loblaw at 04:14 AM on 6 May, 2023

There is a huuuge number of comments on the main post, so that's one tough slog you've made for yourself, Charlie!

My apologies to anyone that followed the link to Eli's Green Plate Effect post, read the comments, and had their head explode. I re-read them this morning, and boy do you need a head vice for the weapons-grade idiocy from a few of the determined commenters. Same goes for the comments Charlie is reading on the main article here at SkS. Take your head vice, don't drink coffee while reading...

I've referred to the Manabe and Wetherald paper a number of times over the years. There is a reason it's a classic. I sometimes find these older papers do a better job of covering some of the basics - stuff that won't be included in later papers because it's all old and well-established.

The same can be said for the IPCC reports - start with number 1, if your climatology background is limited. It could be used as the basic text for an undergraduate climatology course. The newer reports leave so much of that "old ground" out, because they assume that the reader has taken (and passed) the prerequisites.

EGU2023 - Upcoming presentations in Vienna

prove we are smart at 20:06 PM on 21 April, 2023

Thanks for your thoughtful reply, it isn't often ( well in my information world) I hear even a little of good about Davos and the WEF. You know I believe in the inherent good in people and people can change.

But I feel like I am constantly on a seesaw-occassionally balancing evenly-a little down and losing some hope to a little up and we'll muddle through. But the last few years have seem me sink way down and no corresponding way up to match.

Yes I agree with your statement "(SkS can be understood to have been formed in response to the successful misleading marketing by conservative populists trying to preserve and grow their undeserved perceptions of status and superiority)."

As Prof Anderson asks " Will it be a velvet revolution or a violent revolution?" I believe that is coming, it was coming anyway with the widening inequality, climate disruption has sped it up and will spread it more.

Perhaps the harmful media ( sometimes contolled by or controlling those populists) can be called out. Then the majority may be ruled by politicians that believe "life is about planting trees under whose shade you will never get to sit" My seesaw may swing up, perhaps my lucky Australia will go with the former then-i think the larger the percentage of homeless and less resilient citizens, the more the latter will dominate-spilling over to their neighbouring countries.

In this age of misinformation and forgotten morality, we NEED this to happen, from our IPCC- "Targeting a climate resilient, sustainable world involves fundamental changes to how society functions, including changes to underlying values,worldviews, ideologies,social structures,political and economic systems and power relationships."

That is a revolution in every way possible-bring on the leaders and media that can wake us up to a velvet one..

EGU2023 - Upcoming presentations in Vienna

One Planet Only Forever at 07:40 AM on 21 April, 2023

prove we are smart,

I agree in general with your comment and the presentation by Prof. Kevin Anderson, University of Manchester you linked to. The following is in response to the question you ended your comment with.

I would caution against simplistically claiming that ‘the 1%’ or ‘the Davos WEF group’ are ‘the problem’. The fundamental problem is the success of more harmful Populist political game players (Note: Populism is fundamentally misleading, but some of the misleading political players are less harmful regarding climate change). Refer to the SkS re-posting of the Thinking is Power item “Science and its Pretenders: Pseudoscience and Science Denial” and my comment @6 on that posting. (SkS can be understood to have been formed in response to the successful misleading marketing by conservative populists trying to preserve and grow their undeserved perceptions of status and superiority).

Not all of the wealthiest 1% are the problem. The problem is the harmful populist portion of the wealthy and the supporters they have gathered by being misleading about climate science and the required rapid changes of what has developed (note that the harmful populists are harmfully misleading about many matters, not just climate change). And harmful populist people can be found to different degrees in almost every nation, not just the richest and highest climate change impacting nations.

It does appear that the Davos WEF group are doing less than they could to reduce the climate change harm done (they harmfully compromise what could be done). So it is fair to point that out. But I have noticed that the harmful populists currently claim that the Davos WEF group are a threat because of the climate impact restrictions that are being discussed by that group. The conservative populists want more freedom, especially more sovereignty for regions they control to be as harmful as they please. They oppose the ‘globalist progressive improving understanding’ that has been developed collaboratively and collectively globally (like the IPCC results, the Sustainable Development Goals, or the Universal declaration of human rights). Their opposition is due to the reality that the understood actions required to develop sustainable improvements for humanity, to be less harmful and more helpful, require significant changes of their developed preferred beliefs and ways of living.

In closing and responding to: “Is dangerous climate change not really dangerous for the 1%?”

People focused on the pursuit of status relative to others can indeed not consider harmful consequences to be dangerous ‘for them’, especially if they believe those harmed have little ability to ‘do significant harm in return’. And that attitude can exist at all levels of wealth and status. And it is especially true regarding ‘future harmful consequences’ like the type created by accumulating climate change impacts. And those future consequences can be less of a concern if there is ‘doubt about the harm being caused’. Hence the harmful success of populist political players promoting ‘Big Lies’ and ‘Alternative Facts’.

EGU2023 - Upcoming presentations in Vienna

prove we are smart at 15:47 PM on 19 April, 2023

We are putting 40,thousand,million tons of co2 into the tiny 10km space above our heads. As much as scientists explain and educate it's not changing this figure- oh yes, it's slowing down a little-apparantly!

The powerful elite-the billionairs,financiers,ceo's,politicians et all, love the staus quo.

As much as I trust peer reviewed science and this yearly conference will be enlightening for many- the fouty thousand,million tons of co2 is still increasing.

The thirty years of IPCC and its 6 yearly reports, aimed directly at govts worldwide has not been listened to-thousands of peer reviewed science FACTS are ignored.

This wonderful blog site educated me on climate science and was part of the catalyst to develop a big picture view on so much. My opinions can change but for a few years now they haven't. This British climate scientist seems to be saying the right things for me.

Is dangerous climate change not really dangerous for the 1% ?

www.youtube.com/watch?v=VpSWwTjYSj8&t=620s

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