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Comments 201 to 250:

  1. What role did climate change play in this winter’s US freezes, heat, and drought?

    Speaking of severe weather events in the US during the current Winter season...

    Once-in-a-generation flooding possible in Boston — for the second time this year by Matthew Cappucci, Capital Weather Gang, Washington Post, Mar 1, 2018

    'Bomb cyclone' forms as flood threat sparks 'LIFE & DEATH' warning by Faith Karimi & Joe Sterling, CNN, Mar 2, 2018

    Major Coastal Flooding, Hurricane-Force Wind Gusts Expected From Friday's Nor'easter by Jeff Masters, Category 6, Weather Underground, Mar 1, 2018

  2. michael sweet at 23:15 PM on 2 March 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5


    You object to my statement at 153 that "Your claim of 11 inches of sea level rise by 2100 is false." I am sorry.  In attempting to shorten my post I misspoke.  I intended to say that your claim at 152 suggesting that you supported the IPCC 1meter of rise was deliberately false and intended to short cut the discussion.  Your claim has consistently been 11 inches.  Please link to a statement where you supported a 1 meter claim.

    This entire discussion began with your claiming that mitagating AGW would provbide employment and was good.  You have not stated where you will put the millions of climate refugees that Canada will have to take in by 2100.  Please address where you will house all these people in your country.

    You have made the completely usupported claim that reducing CO2 emissions might harm the economy.  I have provided two technical reports that claim reducing CO2 will provide millions of jobs and reduce energy cost at no danger to other sections of the economy (except fossil fuels) and the Stern Report which documented years ago that reducing CO2 would provide much more benefits than harm.  Since then the cost of renewable energy has plummeted so the benefits would be much greater.  I will conceed that Stern has said they underestimated the damage from AGW and the benefit would be greater than they estimated.

    You must provide a reference to a peer reviewed economic report that claims reducing CO2 will harm the economy or withdraw your absurd claim.  

    You must say where you expect the 650 million refugeees from sea level rise to go and describe how Canada will house their share of these persons.  We will leave the refugees from drought unaccounted for.

    You must link a comment you made at SkS where  you support the IPCC median sea level rise as 1 meter and conceed the damage it would cause.  If you cannot you must withdraw your claim at 152 that you have supported that amount of damage.

    In previous comments you have dodged these questions and changed the topic of discussion.  We need to answer them so that the discussion can proceed on.  Please do not change the topic again.

  3. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @181.

    I will admit that it was not clear to me that the period for which you appled that 11" SLR was 2018-2100 (rather than 2000-2100) and that your 11" was therefore not outside the limit set out in the 2017 Climate Science Special Report. It does set a linear projection of  current rates to set that lower limit which is much the same method as you employed. I was wrong to state your 11" lay outside their lowest limit.

    Yet your talk of "casting aspersions on the intent" rather trumps any contrition on my part. You feel content to bandy a level of SLR for the century that sits at the lowest limit.

    If nothing else, this ignores all the places which, balanced by other places which will see less than the average SLR, those places which will see SLR above the global mean, places like Miami which has to contend with a sinking coast line. Note that up-thread @137 the talk that spawned your 11" was of Miami.

    But it is not "nothing else." You may feel your arguments hold water but your argument require the acceptance of unbelievable inconsistencies. You tell us you disgree with "proposals that could seriously harm many of the poor in this world" which sounds all very commendable. You would therefore be arguing that the impacts from AGW-mitigation under,say, RCP2.6 would harm "the poor in this world" far more than the AGW prevented by such mitigation.

    So where does your 11" SLR fit into all this? Doesn't that 2017 Report say that the 12" lower limit to 21st century SLR is very unlikely, and this even under the RPC2.6 scenario? Doesn't it say it is impossible under BAU? You are being insincere or silly with your magicing away multi-foot SLR. You argue that AGW mitigation measures are unnecessary but cite reduced AGW impacts that require those mitigation measures to have been enacted.

    Do you not then see why your arguments here attract the description "false"?

  4. What role did climate change play in this winter’s US freezes, heat, and drought?

    Sunspot cycles in recent decades barely cause a wobble in increasing global temperatures.They might affect winter weather, but aren't by definition the only factor.

    Temperatures in the artic are currently 35 degrees above historical averages, and are affecting fundamental circulation patterns. This seems far more likely to be the most important factor in europes current storms, especially given that a mechanism has been explained by the experts.

  5. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    OPOF @ 182

    I have just reread your comment at 98 and, again, there are so many "factual statements' in there that are unsupported that I do not know where to start.  I do admit that Africa is a problem all by itself. 

    I have zero data to support this but my suspicion is that the poor who have benefitted from fossil fuels are largely in China and India where there are political systems that are not so corrupt as to deny the poor any chance.  But we are a far way from talking climate change.

    When talking about the poor, my real thought is the farmer somewhere who uses some form of locomotion powered by fossil fuels to farm his land and who relies on trucking of some sort to deliver his product to other transmission points which then allow his product to be exported to other parts of the world again relying on fossil fuels.  Without fossil fuels, these tractors will sit in the fields.  They will not be powered by EV tractors and then transported by railroads powered by electricity simply because the cost per product produced will be too high.   The fields will return to nature.  At the same time, the diesel generators needed to provide the electricity for an emergency operation to save his daughter from some life threatening event will not be there.  Until we have a viable storage system for solar power we cannot rely on solar power in outlying areas.  We need diesel power as a backup. 

    You talk about the millions of people who will be displaced by climate change but ignore the millions of people who will die from being cut off from a cheap source of energy that has for the first time allowed them (like the farmer referenced above) to produce a product that is not only for their consumption but can be sold to provide them with the resources to have a better diet or to perhaps fund an education for their children. 

    I will limit my comments to the above because we could go on forever on this topic.  There are no "studies" that I know of that have examined how the poor of this world could survive if we cut off their access to cheap energy. 

    The underlying issue is that we as humans have leveraged energy beyond what our own bodies can produce to develop the society we presently live in.  For the last 200 years it has been fossil fuels that have propelled us to where we are so that you are able to use a computer and the internet to communicate your thoughts on this website. 

    We have realized that the use of fossil fuels is complicating our future because of what it is doing to the atmosphere, our land areas and to the oceans and the organisms that live in it.  So we have to do something about it.  But until we have developed viable ways to replace fossil fuels, we cannot just cut humanity off from this lifeblood of our civilization.  We will have to live and deal with the consequences of not being able to do so. 

    This website is devoted to convincing people that there is a problem.  I clearly accept that there is a problem.  I am not totally convinced as to how sensitive our climate is to the massive increases in CO2 but I agree that we should be "covering our bets".  The real issue is what can we and what should we do about it given the present state of knowledge.

    OPOF, perhaps this is why I have limited my responses to you!! You get into philosophy and that takes a lot of time and words which I am sure most do not want to read.

  6. Actions today will decide Antarctic ice sheet loss and sea level rise

    Antarctica is now discharging 1.93 trillion tons of ice each year, up from about 1.89 trillion tons per year in 2008

    When talking about SLR contribution, you should look at the ice mass balance, i.e. difference between accumulation and discharge. Accumulation number by itself is meaningless, esp. if warming sub-zeroC temperature results in higher snow precipitation. There is an abrupt tipping point though, when air temp reaches freezing point and snow turns to rain but Antarctica is far away from that point yet.

    The only sentence about the ice balance in the article

    When accounting for snow accumulation, the continent is losing about 183 billion tons of ice per year

    Doesn't say how much the balance has been changing in the last decade and if the loss's been accelerating. Hansen 2012, for example claims that the loos has been doubling every 7-10 years and that's the number we should concentrate on here as we talk about SLR prediction as antarctic IS loss wil be dominant contribution to future SLR. But the number's missing in the article.

    The interesting number to note though, is that ice mass exchange due to melting from below and accumulating from above is ATM 10 times bigger than the ice loss (simlarly to CO2 exchange with the ocean). I wonder if it's going to stay that way (i.e. snow precipitation steadily increases in the warming weather until an abrupt tipping point metionaed above) or we are going to see the ratio lowering as the gap in favour of melting inevitably increases. So far, the ratio is big enough so that, theoreticaly at least, we could slow down the melting by inducing more precipitation of we knew how (aerosol spraying?) before the radiation balance & climate is stabilised.

  7. What role did climate change play in this winter’s US freezes, heat, and drought?

    Alchemyst @17

    No offence taken. I realise comments get rushed sometimes, but I wanted it made clear I never made such a claim.

    Basicially you are not reading what I say and responding directly to it. Therefore you totally fail to convince me of anything. Instead you are just repeating yourself.

    You are also contradicting yourself. If you believe the sunspot thory is "just stochastic" ( I assume you meant just a random sort of correlation)  why do you keep repeating it? If you go on repeating it, I will interpret this as meaning you support it.

    The article I referenced took no liberties with the data. Climate scientists have apparently postulated that the current cold weather in Europe is related to current high arctic temperatures and jet stream changes thats all. Its quite a good theory. Are you saying they are not entitled to postulate a theory? Remember we have empirical evidence that the jet stream has changed.

    Nobody has claimed all storms in Europe are being caused  by recent climate change. The recent warming trend in the artic is probably just making them more frequent or longer lasting, as the changed jet stream lets more cold air move south than normal. This may also have happened in the 1940s and 1960's, but its pretty obvious that higher temperatures in recent decades can only make it happen more frequently now.

    The article I mentioned also references Europe and the arctic as a whole, not the UK and greenland. I mean, theres a pretty significant difference.

    And Dana is talking about artic warming is causing je stream changes that are affecting North Americas weather. It seems plausible that if this is the case in America, it could also be the case in Europe. Its stupid to dismiss this, just because we had one particularly cold year in 1962.

  8. One Planet Only Forever at 06:54 AM on 2 March 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5


    You claim "We all have the interests of humanity at heart. We just have different views on what is the best way to get there. When I see proposals that could seriously harm many of the poor in this world and I personally have some reluctance to some of these proposed changes and my perceived view of how these changes could impact them."

    That claim appears to be based on a perceived 'better understanding of what is going on' than I presented in my comment @98. Please explain in detail which specific parts of what I presented in my comment @98 you can 'correct for my benefit' to help me better understand how to best help sustainably improve the future for all of humanity, including genuinely sustainably helping the poorest to live a better life'.

  9. What role did climate change play in this winter’s US freezes, heat, and drought?


    Sorry if I caused offence, it was your reference that was taking liberties with the data. I think that the original article in this site is balanced. The problem starts when these papers are mis reported.  

  10. What role did climate change play in this winter’s US freezes, heat, and drought?


    now do you know the significance of 1962 weather in Britain? I find it exraordinary that 

    "Arctic warmer than much of Europe is a worrying sign of climate change"

    is the headline in the ref  niegelj posted.

    The headline of the newspaper article states that the reversal of temperature between W Europe
    is linked with climate change, yet this pattern of weather has been observed
    (or has got proxies worked out by Mann!) for 350 years.

    page 17 of the Burt report shows that in 1962. Greenland was significantly warmer than normal and Britain had an extremely anomalously low temperature.

     A pattern of weather that peridically hits europe and has been recorded in 26 winters in 350 years with very strong correlation with the low of sunspots activity

    I have never attribted a causal link, yet swampfoxh is strongly insinuating it.

    I think you should moderate others.

    Moderator Response:

    [PS] You appear to arguing a strawman. The "unprecedented" statement in the linked paper states

    "We further find an unprecedented increase in NAJ variance since the 1960s, which co-occurs with enhanced late twentieth century variance in the Central and North Pacific Basin."

    It does not state that jetstream events have not happened in past or that other cold/ warm events have not happened for other causes. Nothing presented so far by you contradicts the paper conclusion.

     Misunderstandings with other commentators would be less likely if you took the approach I suggested further down: State what you accept. State what you disagree with and why.

  11. What role did climate change play in this winter’s US freezes, heat, and drought?

    Alchemyst @8 - 10.

    I didn't personally call anything 'unprecedented'. The article I referenced described how this current stormy cold weather in Europe is well explained by changes to the polar vortex and jet stream and this in turn is caused by climate change. The theory does fit the evidence pretty well.

    I dont know whether the research paper linking cold weather in europe to sunspots has gained wide acceptance. However cold weather In Europe could be partly influenced by sunspot activity as well as changes to the jet stream. 

    The more important point is the arctic has been warming for decades here . There were some hot individual years back in the 1940s, however temperatures are clearly higher now "on average" than at any point in the last 100 years and this is the most important thing to understand. This can all potentially change weather systems a lot, because of how weather systems originate. And arctic temperaturtes are predicted to get a lot higher yet by 2100.

  12. What role did climate change play in this winter’s US freezes, heat, and drought?


    I have never stated that there is any causal link between cold winters in W europe and sunspots.

    here is the peer review report linking sunspot activity with cold weather in England,


    Please read the royal met office report warm air every so often slip up by Greenland, 1962 and 2017 and seemingly 2011(not checked).  These pulses in cold temperature have been going on for over 300 years and the last three have had warm temperature anomalies in Greenland.

      I think that the onus to link this effect to climate change is on the proponents at the moment sunspots has more credibility, but if you want my opinion it is probably stochastic. 

  13. What role did climate change play in this winter’s US freezes, heat, and drought?

    Swampfox, there is a reference to the royal metrological office, from the  Imperial College London the top science university in Britain (OK Cambs is pretty good to). Now you cannot get more authority than that. However if you wish to dispute the met office and Imperial college! The data from the met office report is all peer reviewed

    Seemingly 2011 had a warmer Greenland (7.8 C) than this year, it is only a blog but it refers to a danish met office document. that was the same winter as the last big freeze in europe.

    As to sunspots, there is a peer reiew out there that these events in western europe have a strong corrolation, that does not give any link though it is intriguing is it real effect or hocus pocus, I do not no, for me its a bit spooky, I do not want to believe it. but there it is

    I'm not really bothered if you do not give creedance to the fact that this weather pattern occurs regularly, it does. Warm air goes up Greenland cold air comes through Europe first law of thermodynamics.

    the pattern in the 1962-3 winter temperature anomalies in the imperial college match closely the current situation.  

  14. What role did climate change play in this winter’s US freezes, heat, and drought?

    alchemyst may not notice that he raises a common issue we layperson's often deal with on a science site.  Let me explain: A peer-reviewed "discovery" will present a set of facts (with or without causality).  The evidence support the facts, even though there is a slight chance that another set of evidence might support the facts.  To me the problem is connectivity.  Let me eplain this problem:  Your dog gets hit and killed by a car.  The "evidence and facts" that cause the death of your dog won't change the fact that your dog is dead, but oftentimes people go on and on about the efficacy of their given set of facts and argue their set of facts against your set of facts.  Meanwhile, the dog is still dead.  I think Alchemyst owes us a lot more corroboration (and proofs) that his "climate events" in the 1960s are of the same "pedigree" as the climate events described by the CCL people above or that his 1960s climate events make the 2018 climate events the result of sunspots (etc) rather than increases in average planetary temp (etc).

    Am I "all wet" about this point of view?

  15. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    MA Rodger @ 180

    Am I missing something here on simple math (not regression analysis)?  If the lower limit predicted by the Climate Report is 12" for the period 2000 -2100, then that means, based upon simple math, that we have about 10" of sea level rise to go from 2020 to 2100 (you will see I am rounding).  So how is my 11" SLR even outside the range?

    But my basic point, which I have made in other comments on this website (that referenced Steve Koonin) is that the use of the word "false" (by michael sweet) rather than the word "incorrect" as used by you above, is inappropriate unless you truly believe that the person making that statement has some ill intent. 

    We all have the interests of humanity at heart.  We just have different views on what is the best way to get there.  When I see proposals that could seriously harm many of the poor in this world and I personally have some reluctance to some of these proposed changes and my perceived view of how these changes could impact them. This is not ill intent.  We just disagree on things but our disagreement is based upon a different view of the facts utilizing our powers of reason. There is no problem with this.  It is casting aspersions on the intent of people that I have a problem with.

  16. What role did climate change play in this winter’s US freezes, heat, and drought?

    A slew of high-quality articles about the recent heat wave in the Arctic and its impact on weather in the Northern Hemisphere have been published around the world over the past few days. I have posted links to some of them on the SkS Facebook page. Here's listing of the links I have posted to date.

    Has the Arctic Finally Reached a Tipping Point? by Brian Kahn, Science, Earther, Feb 23, 2018

    Really extreme' global weather event leaves scientists aghast by Peter Hannam, Sydney Morning Herald, Feb 26, 2018

    North Pole surges above freezing in the dead of winter, stunning scientists by Jason Samenow, Capital Weather Gang, Washington Post, Feb 26, 2018

    Arctic warmer than much of Europe is a worrying sign of climate change by Stuart Braun, Deutsche Welle (DW), Feb 27, 2018

    Arctic heat spasm caused by stratosphere warming has a southern cousin by Peter Hannam, Sydney Morning Herald, Feb 28, 2018

  17. What role did climate change play in this winter’s US freezes, heat, and drought?

    Nijelj  I believe you live in the southern hemisphere. This unprescedented weather is well known here and yes I remember 2011 where it was some 20 C below normal temperatures, and yes the sunspots were low that winter.

    I read your newspaper report now have a read of mine. 

    "So cold the SEA froze: Current cold snap is nothing compared to -22C winter of 1963",

    In 1962-63 sea ports were frozen. This has certainly not happened this year

    The daily mirror

    This type of weather is well known in Europe and is not unprescedented as your report says. Please look at the weather map from the Royal Met office and yes it does seem that the arctic get the atlantic weather and western europe gets frozen. other similar instances are documentad in the report. please note the comment, that the meteorologist expects these events to become rarer with climate change. somehow you just can't win.

    “The winter of 2010/11 was a rare weather event, even in the context of the 352 years of the Central England temperature record. Yet while the odds of such an event have lengthened as a result of human influence on climate, such unlikely events can still happen, as the winter of 2010/11 demonstrated.” – Nikolaos Christidis and Peter Stott, Bulletin of the American Meteorological Society , July 2012

  18. What role did climate change play in this winter’s US freezes, heat, and drought?


    Moderator Response:

    [DB] Image resized to 450 width.  Please limit all further images to that or less.

  19. What role did climate change play in this winter’s US freezes, heat, and drought?

    People are commenting (comment 1 and 2)that this weird warming of the pole is unprescedented, Yet 1962 we had the same pattern and this minor cold wave bit of cold weather in western europe is nothing as to what happened in 1962 to 63. It was for more than 3 months. I thought it was common knowledge what had happened in Britain in 1962, indeed 1948, and 1933 also had severe weather in Britain. for whatever the reason it seems to be corrolated with low sun spot activity, but it is certainly has prescedent.

  20. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @178.

    The US Global Change Research Program Fourth National Climate Assessment - Volume I sets out the 2000-2100 GMSL rise in its Executive Summary as:-

    "1.0–4.3 feet (30–130 cm) by 2100 (very high confidence in lower bounds;  ...  low confidence in upper bounds for 2100)."

    Your 11" SLR by 2100 (+27.94cm) lies outside the range 30-130cm with its "very high confidence in lower bounds". To suggest your 11" is "just about "dead on" the lower limit" is incorrect. It is outside the limits. And (rounding errors aside) it also sits outside the limits set out in IPCC AR5 Chapter 13 Table 13.5, an assessment which is often criticised for having under-evaluated SLR.

    So do you consider an apology is truly in order? And when will you make it?

  21. One Planet Only Forever at 14:36 PM on 1 March 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5

    “I just have to admit that your comments are so long and have so much in them that I honestly give up”

    Really? I felt that my first comment to you @15 was fairly concise. So were my comments @32 and @44.

    My comment @46 was also rather clearly to the point and founded on the content of my previous comments, and the comments of others. It included:

    “I have to ask if you understand, accept and support the need for the global impacts of human activity to be limited to a level that climate science indicates has a good chance of less than 2.0C increase of global average surface temperature above pre-industrial levels.

    "If you disagree with that understanding, that all of the global leaders agreed was the proper understanding of what was needed to responsibly limit the harm done to future generations, please provide the 'substantial new climate science evidence' that was not part of the basis for the understanding and acceptance of the Paris Agreement. 'Substantial new climate science evidence' is the only thing that would justify changing such a decision (not the election of a different leader in the USA).”

    My comment@53 was lengthier to try to make the understanding clearer to you. And the lack of any response from you to my earlier comments led to the even longer @62, but mainly because I included the large quote from the UN Report.

    My comment @63 was another attempt to help you more correctly understand this issue. And my comment @70 was a further attempt to get a reasoned and justified answer in response to your first suggestion that you would respond to my comments (your comment @69).

    My comment @98 was a more expansive attempt to present information that would help clarify understanding of issues you seemed to struggle to grasp the correct understanding of.

    My reply @133 and @136 to your comment @132 were added attempts to help you correctly understand what I was presenting, as was my comment @139. And my comment @143 elaborated on the sea level rise matter to help you correctly understand my points. As were my comment @146, @148 and @170.

    Then comes your comment@173 with the opening para leading me to provide the above summary and explanation.

    Your second paragraph is full of misunderstandings or incorrect assumptions about me, and an apparent wish to not admit that my MBA may give me a better understanding of the Present Value of money and its correct use.

    And your last para is full of gross misunderstandings or deliberate misrepresentations of my awareness and understanding of what is going on, other than 'our different philosophies'. Your 'philosophy' appears to be to try to excuse understandably unacceptable things that have developed. My 'philosophy' is to try to help people better understand what is really going on and the 'changes of understanding required regarding what has developed' (what you call - "... convincing our governments (and the populace) that certain actions should be taken.").

    The political realities of the 'Real World' admittedly delay correcting understandingly unacceptable developments. But when the corrections occur they can be very rapid. History is full of dramatic rapid corrections of things that had unacceptably over-developed in a harmful unsustainable way. The correction of the burning of fossil fuels is unlikely to be an exception.

    I have tried to help you be more aware of and correctly understanding of my understanding of what is going on. But you do not appear to be interested in correctly understanding what I present.

    Thank you for presenting case study examples of the type of thinking and claim-making that I understand needs to be corrected. Even if you choose not to better understand the many aspects of this issue, others may learn from your example. And I am more certain that I have a Good understanding of what is going on, the motivations of those who try to deny (or delay, or diminish) the corrections of what has developed that climate science has identified are required for the benefit of the future of humanity (there I go - that idealism that people can learn to change their minds and help improve the future for humanity, that you appear to disagree with).

  22. What role did climate change play in this winter’s US freezes, heat, and drought?

    Sorry for appearing to be repeating stuff,  but the moderators message wasn't there when I pressed submit.

  23. What role did climate change play in this winter’s US freezes, heat, and drought?

    Alchemyst @5

    "Please could somone tell me how do we know what the jet stream was like 290 years ago when it was only discovered in the mid 20th centurey?"

    I didn't know either, but If you actually read the research link "2018 study in nature communications" in the article you find they used tree rings.  The research is outside my knowledge, however this media article describes it in plain language.

    "The rings of trees from Britain and the northeastern Mediterranean region tell a long history of the jet stream. That's allowed a team of scientists to piece together 300 years of the flow of the North Atlantic jet stream in summer."

    "So we used the wood density, and that's been found to be very sensitive to temperature conditions. So in cold summers you'll have less dense wood, and in hot summers you'll have more dense wood," said Valerie Trouet, an assistant professor of tree-ring research at the UA."

    "Trouet said since the 1960s there have been more instances of the jet stream moving off its average position. When the North Atlantic jet stream is more north, Britain is much warmer than normal. In Italy and the Balkans, there are floods and colder conditions. That's reversed when the jet stream has a more southerly track."

  24. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    michael sweet @ 177

    I see what you are saying about the Climate Report upper estimate but I will reserve comment on how much weight the Climate Report places on the 8 ft number until I have read the chapter on sea level rise.  From the summary you cannot get any sense of what risk they assign to this.  It obviously has to do with "what if" issues relating either to the Greenland ice sheet or the West Antarctic glaciers. 

    But you have ignored my request to withdraw your following statement made at 153:

    "Your claim of 11 inches of sea level rise by 2100 is false.

    At the time you made this statement you were fully aware that I was using this figure as a measurement from today to 2100 and not from 1880. 

    Given that this 11 inch "linear guesstimate by me is just about "dead on" the lower limit given by the Climate Report, I would ask you why you would use such a pejorative term as "false" when in fact it is the actual figure (one inch off) used by the Climate Report.

    Was my statement false? I think I am owed an apology. 

    I am a little disappointed that the Moderator has not weighed in on my behalf.  I am sure he or she well knew that my use of 11" was not off the mark.  It was very clear that I was referencing 2018 to 2100.  For that matter the Climate Report is using 12" from 2000 if I am not mistaken.  So if anything I am higher than the lower limit.  

  25. What role did climate change play in this winter’s US freezes, heat, and drought?

    that the jet stream has become increasingly wavy over the past 50 years, to a degree unprecedented in the past 290 years,

    Please could somone tell me how do we know what the jet stream was like 290 years ago when it was only discovered in the mid 20th centurey?

    Moderator Response:

    [PS] If you had bothered to read the linked paper in the article, it would tell you. This is a site for the discussion of science of global warming. Please dont try to substitute in rhetoric instead.

    Perhaps this would be a useful guideline to create a sensible discussion since you clearly dont like the result. Which of factors here are you disputing and why.

    1/ That deep waves in the jetstream cause extreme weather (heat wave, heavy snow)?

    2/ That jetstream is currently weakening and becoming more wavy?

    3/ That climate change is causing the changes to the jetstream?


  26. What role did climate change play in this winter’s US freezes, heat, and drought?


    I'm afraid some brits tell me that this cold spell is nothing like what happened in 1962

    Moderator Response:

    [PS] and have they data to back that up? Where does "1962" come from anyway. I dont it in nigelj comment nor linked reference.

  27. David Kirtley at 10:48 AM on 1 March 2018
    What role did climate change play in this winter’s US freezes, heat, and drought?

    David Roberts has a few good quotes on this topic of how "climate change" is related to extreme weather. This one is from when he wrote for Grist:

    There is no division, in the physical world, between “climate change storms” and “non-climate change storms.” Climate change is not an exogenous force acting on the atmosphere. There is only the atmosphere, changing. Everything that happens in a changed atmosphere is “caused” by the atmosphere, even if it’s within the range of historical variability. Climate change is just the term we use to describe those changes.

    And more recently, writing for Vox on last year's hurricanes:

    “Did climate change cause this hurricane?” is a malformed question.

    Climate change does not cause things, because climate change is not a causal agent. “Climate change” is a descriptive term — it describes the fact that the climate is changing. What’s causing the changes is an increase in heat energy trapped in the atmosphere, due to greenhouse gases.

  28. What role did climate change play in this winter’s US freezes, heat, and drought?

    A similar thing is happening now with  Europes unusually cold weather and very high arctic temperatures. This article discusses the events and the possible mechanism.

  29. Philippe Chantreau at 04:49 AM on 1 March 2018
    What role did climate change play in this winter’s US freezes, heat, and drought?

    It would be good also to mention more specifically the extraordinary Arctic winter event that has unfolded this year, with temperatures above freezing at extreme lattitudes in the dead of the polar night and the lowest sea ice extent recorded for January.

    WaPo article previously referenced by OPOF on another thread. Links to the Danish Meteorological Institute. Arctic Temperatures as high as 20 deg C above normal.

    Sea ice is not tracking any better now, NSIDC shows that we are fast approcahing the max extent time and have barely made it above 14 millions square kilometers. Of all the features of climate change, I find the loss of Arctic sea ice to be one of the most worrisome; it is truly a geological scale event that we are witnessing in a blink of an eye.

  30. michael sweet at 03:53 AM on 1 March 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5


    From paragraph 6 of the executive summary of the US Climate Report 2017 which I have copied for you before here at SkS:

    "Global average sea levels are expected to continue to rise—by at least several inches in the next 15 years and by 1–4 feet by 2100. A rise of as much as 8 feet by 2100 cannot be ruled out." my emphasis

    They put this number at the top so everyone would see it.

    When they say they have "low confidence" in their upper bounds that means they think they may have underestimated the high end and that it is possible for it to be much higher.  That is no reason to be confident about your low ball number, it is a reason to be less confident in low numbers.  They are very confident that sea level rise will be higher than their low estimate.

    Apparently they are estimating rise from today so you have to add 9 inches to obtain total rise.

    As I have quoted to you before and above, 8 feet is what they think is a possible maximum before adding the acceleration from Nerem and the recently documented destabilization of the West Antarctic ice sheet. Engineers are generally required to design public works so that they survive the worst case ie 8 feet of sea level rise. 

    "Plan for the worst and hope for the best" is appropriate.  Planning for the best and hoping that it works out is a receipt for disaster

  31. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    michael sweet @ 153

    I have now read the Executive Summary of the US Climate Report 2017 and look forward to reading Ch 14 on sea level rise.  In the above post you state that my claim of 11" from now to 2100 "is false" and you exhort me to consider a possible sea level rise of 8 feet by 2100.

    But here is what the Executive Summary has to say about sea level rises for the period up to 2100:

    "Relative to the year 2000, GMSL is very likely to rise by 0.3–0.6 feet (9–18 cm) by 2030, 0.5–1.2 feet (15–38 cm) by 2050, and 1.0–4.3 feet (30–130 cm) by 2100 (very high confidence in lower bounds; medium confidence in upper bounds for 2030 and 2050; low confidence in upper bounds for 2100). Future emissions pathways have little effect on projected GMSL rise in the first half of the century, but significantly affect projections for the second half of the century (high confidence)."

    So my suggestion of 11" is pretty close to the low range prediction of the Climate Report of 1.0 ft.  Is it not a little extreme to call my "linear" estimate of 11" "false"?

    And as for your 8 ft number, I know somewhere else in the Report this "outside" number is used (I think based upon the unrealistic RCP 8.5) but as to its upper bound estimate of 4.3 ft the Climate Report states that it has "low confidence" in this estimate.  So if the Report has "low confidence" in 4.3 ft then what reliance should be place on 8 ft? 

  32. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    What MA Rdger said times two.

    "You fail to differentiate between a bunch of AGW deniers and a grown-up call for more action to mitigate AGW" describes NorrisM perfectly.

    Lomborg has no expertise in environmental matters.  He has a degree in Political Science, not science.  He has never published a peer reveiwed paper on an environmental issue.   He has gained fame for claiming expertise he does not have and writing OP-ED pieces that support raping the planet.

    It is typical for deniers to cite an industry shill as an environmental expert.

  33. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @173,

    You clearly continue to have "it wrong."

    The Copenhagen Consensus on Climate argues for nothing in common with that called for by the  Global Apollo Programme. You will note that the Copenhagen Consensus On Climate considers amongst other apparent options action to mitigate AGW, mitigation being predicated with the following assertion:-

    "Humankind is changing the earth’s energy balance. It is doing so by releasing large amounts of greenhouse gas (GHGs) emissions into the atmosphere. While it is still a matter of scientific debate how much the build-up will alter our climate, there is little doubt that at least some change will occur, with potentially serious ecological, social and economic implications."

    So there is even remaining doubt attached to there view that 'potentially' there will eventually be serious implications from AGW.

    This is a different ballpark from the Global Apollo Programme who express no doubt and bucket-loads of urgency for a big increase in mitigation measures.

    "By 2035 the concentration of carbon dioxide in the atmosphere will exceed the critical level for a 2 ̊C rise in temperature and on current policies the temperature will eventually reach 4 ̊C above the pre-industrial level. This is the central forecast, implying a 50% chance of still higher temperatures. We must take action to prevent this, by radically cutting the world’s output of carbon dioxide (see Figure). We must reduce the use of energy and we must make the energy we use clean i.e. free of carbon-dioxide emissions. This Report is about how to make energy clean."

    You fail to differentiate between a bunch of AGW deniers and a grown-up call for more action to mitigate AGW.

  34. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    OPOF @ 170

    Let me apologize for often not replying to you when I have made replies to others at the same time.  I just have to admit that your comments are so long and have so much in them that I honestly give up.

    I fully respect your qualifications as an engineer who even worked in the Canadian oil and gas sector before moving out of Alberta.  I am sure that one of your reasons for moving out of Alberta was the attitude of Albertans to anything that could impact their welfare which is clearly tied to the production of oil and gas.  I have to admit that when I am in Calgary on business I tend not to get into discussions of climate change because it does not go over well.  With my good friends I can have some discussion but even then I watch what I say.  Somewhat like suggesting to  Republicans while in the US that there were some good things about Obama.  

    But there is another reason why I often do not respond which relates to our different philosophies and what I consider to be your somewhat unrealistic view of the political systems under which we operate, at least in the Western World.  The key word is "democracy".  There is no world government and everything we do has to be based upon convincing our governments (and the populace) that certain actions should be taken.  I often see (perhaps wrongly) a desire in you that we had some rational benevolent world dictator who could wave a magic wand and make everything right.  Because of that there is much we disagree on even if we agreed in principle on many things if there were such a benevolent dictator in charge.  I just think it is wasted time not taking into account the political realities which exist in the world.

  35. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    michael sweet @ 169

    I clearly had it wrong. 

    First of all, the "Council of Scientists" as I called it is the "Copenhagen Consensus" which is a collection of scientists who do believe that the best expenditure of funds to battle climate change is to invest significant capital into research into green technologies rather than cutting off the public's present use of fossil fuels without viable alternatives for major sectors of the economy and world (read storage for one example).

    But here is the connection to Lord Stern. 

    On Lomborg's website referencing the Paris Agreement and what it does or does not achieve here was a reference to the Apollo Program which has the same aims:

    "Copenhagen Consensus has consistently argued for a R&D-driven approach. Fortunately, more people are recognizing that this approach is cheaper and much more likely to succeed –including the Global Apollo Program which includes Sir David King, Lord Nicholas Stern, Lord Adair Turner and Lord John Browne."

    So Lord Stern is not part of Bjorn Lomborg's Copenhagen Consensus but is part of a group which seems to have the same objectives.

  36. 2018 SkS Weekly Climate Change & Global Warming Digest #5


    By all means enjoy your vacation, and cut back on what my wife calls "climate blogging". There will still be issues to discuss when you get home - we won't have solved them all by then.

    What OPOF describes as "the impacts they impose on those others are less than the benefit they get for themselves," fall into what economists call "externalities": I get personal benefit while someone else bears the costs. Great for me in teh short term if I'm selfish; not so good for society (and maybe me) when the poor suffering peasants get uppity and find weapons to fight with.

    As for the IPCC reports: keep in mind that the three working groups have completely different areas of study. WG I is climate science. The other two deal with economic and social issues. Also keep in mind that there is a hierachy of information here:

    1. Summaries provide, well, summaries of the main reports.
    2. The main reports go into much more detail.
    3. Ultimately, even the main reports refer to the scientific literature. It's in the scientific literature that you will find the greatest level of detail.
  37. One Planet Only Forever at 10:12 AM on 28 February 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5


    I hope that your understanding of present value of money and the related assumptions is consistent with my reply to scaddenp@165.

    I have an MBA and decades of observation and consideration of what is going on as the basis for that understanding. But it does not even require a business class in economics to understand that any evaluation that combines/compares future benefit/cost is only legitimate if the same people experience all the benefits and costs now and into the future of what is evaluated.

    Any other evaluation would be like a person justifying doing something that causes costs/problems/harm for other people by declaring that the impacts they impose on those others are less than the benefit they get for themselves, with the comparison done as 'they (not the harmed person) sees it'.

    Properly understood, there is no need for complicated assessments to understand what is acceptable and what needs to change regarding climate change. Any negative impact on future generations is unacceptable. And the politics of popularity in pursuit of bargaining to get away with creating more future harm, delaying the correction of the incorrect things hat have developed, can be seen clearly as being grossly unacceptable.

    As for International Leadership, the UN led the development of the IPCC, Kyoto, the 2015 Sustainable Development Goals, and the Paris Agreement (along with many other international leadership actions that are contrary to the damaging unsustainable developed desires among humanity).

    I am glad you appear to appreciate the unacceptability of what has developed and have the abiliity to recognise the specific players in humanity who deserve penalties for their behaviours. But I have yet to see you bluntly admit that recognition of reality. Your presentations tend towards excusing the bad behavers among us, and tend towards finding and arguing for excuses for their understandably unacceptable harmful unsustainable behaviour.

  38. Scientists have detected an acceleration in sea level rise

    I thought much the same as Riduna. It's human nature to try to reach personal conclusions on what it all means, even if the data is not 100% conclusive. I think a smart assessment would be definitely one metre by end of century, with a very distinct possibility of more. 

  39. 2018 SkS Weekly Climate Change & Global Warming Digest #5


     I get nothing from GOOGLEing Lomborg Stern "Council of Scientists" and also nothing from Lomborg "council of Scientists".  Can you provide a link supporting your unbelievable claim that Lord Stern would work with Lomborg.

    It is easy to make false claims.  Please support your claims.

  40. Scientists have detected an acceleration in sea level rise

    As pointed out by Dr Abraham, sea level rise is primarily caused by loss of polar ice and, to a lesser extent, thermal expansion of water. The prediction of a 65 cm. rise in sea level by 2100 appears to be based on the assumption that loss of polar ice does not change over the next 82 years.

    Is this true – or is the rate of polar ice loss likely to accelerate? The latter seems certain, a view supported by eminent specialist climate scientists, including Drs. Rignot, Velicogna and Hansen, who point to on-going acceleration in the rate of ice loss from the three polar ice sheets.

    They point to Arctic amplification which is accelerating both surface melt and glacier discharge from the Greenland Ice Sheet and to the effects of formation of warming bottom water on the West Antarctic Ice sheet grounded on the seabed. These developments can only result in much more rapid acceleration of mean global sea level rise.

    How much will sea level rise by 2100? At present, this can not be accurately determined but a multi-metre rise by 2100 is certainly possible and is becoming increasingly likely with accelerating polar ice mass loss.

  41. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @ 160 & 164 is a website dedicated to just this particular and worrying issue. It has lots of graphics and articles to explore.

  42. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    scaddenp @ 162

    About the only two things I took away from my undergraduate economics degree was the present value of money and the importance of assumptions in any analysis (ie my joke about the economist's contribution to opening the can of beans on the desert island).

    The arguments of what discount rates to use render any discussion about future costs of climate change very problematic.  The assumptions used again make the discussion very difficult.

    Again, my point is that governments have a lot more resources than we do to come up with some estimates of the costs but we once again meet up with the problem that there is no world body that has any power to do anything about it.

    The information that China's population is more at risk than any other nation state is somewhat interesting.  If there is one thing the oligarchy in China is concerned about is staying in power and keeping its nation united.  This should be a strong incentive for China to come up with innovative ways to deal with climate change knowing that they have 50 million people to protect. 

    I hate to say it but I look at Florida with some amusement.  Did they only discover yesterday that some areas are only 12" above sea level? Or was it not a problem when it was 15" perhaps 10 years ago?  I have no idea what the annual rate of sea level change is in this area. 

    As for Lomborg, I have read his book and I recall the reception I received on this website bt making reference to him.

    I might be mistaken but I believe that Stern has joined Lomborg's "council of scientists".   I am sure I will be corrected if I am wrong on this.  Even if that is the case I am not sure what that means as to whether any of his views have changed.  I do not follow Lomborg's website.

  43. One Planet Only Forever at 02:32 AM on 28 February 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5

    in my prevous comment the second last paragraph is intended to end at ... flawed global economy.

    More could be stated, but 'is leaving for' is a legacy of original phrasing that I made a last second edit of.

  44. One Planet Only Forever at 02:19 AM on 28 February 2018
    2018 SkS Weekly Climate Change & Global Warming Digest #5


    When you develop the understanding that future generations are 'others' and that the only sustainable perceptions of wealth are the perceptions developed due to truly sustainable economic activity, you understand that even the criticized 'lower discount rate' used by Stern is unacceptably high.

    One of the recommendations in the detailed back-up of the UN Sustainable Development Goals is for the discount rate to be zero, to be fairer to future generations. Even a discount rate of zero isn't truly 'fair' to future generations.

    A proper evaluation would simply identify all of the unproductive costs and reduced resources (including decimated agricultural land due to unsustainable industrial agriculture) 'Others in the future to have to deal with' that are the result of unjustified Winning by Private Interest pursuits of benefit that incorrectly over-developed in the flawed global economy is leaving for.

    The correction of those unsustainable incorrectly over-developed perceptions is contrary to the Private Interests of many already very fortunate people who refuse to give up 'pursuing more benefit any way they can get away with'.

  45. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    Bob Loblaw @ 161 & 163

    Thanks for the reference re ocean acidification. 

    As for the studies, I printed the 50 page assessment of the IPCC that I read which is at home so I will defer trying to locate the information now.  My wife is not impressed with how much time I am spending on my notebook so I do have to watch my time spent.  Clearly I have not read everything published by the IPCC but what I did read was the IPCC making the statements that I have referenced above which obviously took into account everything they had published.  I will locate it when I am home in late March.

  46. Impact of climate change on health is ‘the major threat of 21st century’

    It does not matter one bit if it is fully automated or so called "regenerative" when the climate swings wildly from record heat and drought, to record cold and atmospheric rivers dumping 20" of rain in a day or two flooding out all your efforts.

    Regenerative agriculture was a great concept. I wish we could have adopted it 50 years ago.

  47. Impact of climate change on health is ‘the major threat of 21st century’

    @6 Riduna,

    It's not the tools of agriculture you have wrong, it's how those tools are used. And yes Australian farmers are inventive. Here is one example: 

    Why pasture cropping is such a Big Deal

    Pasture Cropping: A Regenerative Solution from Down Under

    And a 10 year case study of the above + several other inventive Australian farms also developing other similar types of regenerative agriculture? 

    Liquid carbon pathway unrecognised


    "If all farmland was a net sink rather than a net source for CO2, atmospheric CO2 levels would fall at the same time as farm productivity and watershed function improved. This would solve the vast majority of our food production, environmental and human health ‘problems’." Dr. Christine Jones

  48. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @ 160:

    There is a good but lengthy series of posts on ocean acidification at SkS. The last post in the series (with links to all other parts), is here:

  49. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM - try the Stern review. Attempts to show otherwise (eg Lomborg) can only do so by not talking about risk and positing impacts lower than anything in the IPCC studies. There have been numerous criticism of Stern for discounting rates, but also plenty of concern (even from Stern himself) that in hindsights, the risks were underestimated.

    Maybe a new analysis might do better, but to make a convincing case for not mitigating, someone needs to publish a study with that kind of breadth that also makes a realistic assessment of risks and impacts. So far, I have only seen hand-wavy stuff or over-sold critiques of Stern that dont change the overall conclusion.

  50. 2018 SkS Weekly Climate Change & Global Warming Digest #5

    NorrisM @159:

    Before I go on a wild goose chase into the IPCC reports, can you clarify just what you have looked at to support your statement that it "has very little in it on actual numbers"?

    I am wondering in particular if you have looked at the full reports for Working Groups II and III.

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