Arguments
Newcomers, Start Here
Posted on 15 August 2010 by John Cook
Skeptical Science is based on the notion that science by its very nature is skeptical. Genuine skepticism means you don't take someone's word for it but investigate for yourself. You look at all the facts before coming to a conclusion. In the case of climate science, our understanding of climate comes from considering the full body of evidence.
In contrast, climate skepticism looks at small pieces of the puzzle while neglecting the full picture. Climate skeptics vigorously attack any evidence for man-made global warming yet uncritically embrace any argument, op-ed, blog or study that refutes global warming. If you began with a position of climate skepticism then cherrypick the data that supports your view while fighting tooth and nail against any evidence that contradicts that position, I'm sorry but that's not genuine scientific skepticism.
So the approach of Skeptical Science is as follows. It looks at the many climate skeptic arguments, exposes how they focus on small pieces of the puzzle and then puts them in their proper context by presenting the full picture. The skeptic arguments are listed by popularity (eg - how often each argument appears in online articles). For the more organised mind, they're also sorted into taxonomic categories.
Good starting points for newbies
If you're new to the climate debate (or are of the mind that there's no evidence for man-made global warming), a good starting point is Warming Indicators which lays out the evidence that warming is happening and the follow-up article, 10 Human Fingerprints on Climate Change which lays out the evidence that humans are the cause. More detail is available in empirical evidence that humans are causing global warming. Contrary to what you may have heard, the case for man-made global warming doesn't hang on models or theory - it's built on direct measurements of many different parts of the climate, all pointing to a single, coherent answer.
Another good starting point is the SkS climate graphics page, with each graphic featuring links to informative SkS material. Good introductions to climate science can be found at Global Warming in a Nutshell and The History of Climate Science. You could lose yourself for hours in those pages!
Smart Phone Apps
For smart phone users, the rebuttals to all the skeptic arguments are also available on a number of mobile platforms. The first Skeptical Science app was an iPhone app, released in February 2010. This is updated regularly with the latest content from the website and very accessible in a beautifully designed interface by Shine Technologies. Shine Tech then went on to create a similar Android app which has some extra features missing from the iPhone version. A Nokia app was also created by Jean-François Barsoum (this was one of the 10 finalists in the Calling All Innovators competition).
As well as the list of rebuttals, Skeptical Science also has a blog where the latest research and developments are examined and discussed. Comments are welcome and the level of discussion is of a fairly high quality thanks to a fairly strict Comments Policy. You need to register a user account to post comments. One thing many regulars are not aware of is you can edit your user account details (to get to this page, click on your username in the left margin).
Keep up to date by email, RSS, Facebook or Twitter
To keep up to date on latest additions to the website, sign up to receive new blog posts by email. There's an RSS feed for blog posts and for the engaged commenter, a feed for new user comments. I recommend you follow the Skeptical Science Twitter page as I not only tweet latest blog posts but also any other interesting climate links I happen upon throughout the day. New blog posts are also added to our Facebook page.
About John Cook
Lastly, for those wondering about who runs Skeptical Science, the website is maintained by John Cook. I studied physics at the University of Queensland but currently, I'm not a professional scientist - I run this website as a layman. People sometimes wonder why I spend so much time on this site and which group backs me. No group funds me. I receive no funding other than the occasional Paypal donations. As the lack of funding limits how much time I can spend developing the site, donations are appreciated.
My motivations are two-fold: as a parent, I care about the world my daughter will grow up in and as a Christian, I feel a strong obligation to the poor and vulnerable who are hardest hit by climate change. Of course these are very personal reasons - I'm sure everyone comes at this from different angles. I go more deeply into my motivations in Why I care about climate change.
The SkS Team
However, there are many more who make invaluable contributions to Skeptical Science. There are a number of authors who write blog posts and are currently in the process of writing all the rebuttals in plain English. Translators from all over the world have translated the rebuttals into 15 different languages. There have been contributors to the one-line responses to skeptic arguments, proofreaders, technical support from boffins who understand computers a lot better than myself and commenters whose feedback have helped improve and hone the website's content. Skeptical Science has evolved from a small blog into a community of intelligent, engaged people with a commitment to science and our climate.
Virtually all of the USHCN warming since 1973 appears to be the result of adjustments NOAA has made to the data, mainly in the 1995-97 timeframe.
Does this deserve a new post at SKS?
[DB] Curious, that an "old fashioned" scientist up-to-speed enough on technology to be able to post on this forum was not then able to take the next step and search via Google for the requested data?
Conveniently, links to all said "raw data" are available (as others have noted) here:
The collector's casual/informal notes are an unnecessary complicating factor (adding bias/noise) for old-fashioned scientists seeking to replicate the work of others. Unless your intent was merely to "audit" the work already done...?
If you still can't track down what you are looking for, perhaps you could be a tad more specific. Let us assume you are focussed on a particular aspect of the theory of global warming due to so-called 'greenhouse gasses': What data are you seeking? Do you want original, handwritten documents and recording equipment traces going back 150 years, or would some form of electronic conversion and delivery (which then requires you to trust the source) be acceptable?
Are you in a position to recreate all the experiments which produce the data you are looking for, in order to confirm their results, or will you trust that the experiments were performed correctly and observed accurately? At what point in the chain of evidence do you say "I will believe the evidence supplied this far, but no further"?
To be sceptical is desirable; to attempt to retrace the steps of every worker in the field since the year dot would be perverse.
At RealClimate they have links to all the data you could ever want. Asking this question indicates that you are not serious in your search, since you would have found the data with a simple GOOGLE search. Do you have the ability to analyze mountains of data? Can you point to an analysis you have done?
It was once a common denier meme to claim they want to see the data. Once it was posted to the net they have not looked at it. Most deniers have moved past this stage, since all the data is available.
This person claims that "The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today. To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today-- 4400 ppm."
Has anyone else here looked at this? Maybe this guy's geology is out of date? I am not a geologist and I don't have expertise in the area of ancient temperatures versus CO2 levels.
Check out this SkS article and post any further questions or comments there. The short of it: the sun was much less active during that period.
More recently, a number of high resolution strata have been found which enable a more detailed examination of the record. The situation in 2006 was summarized by Dana Royer (PDF). Since then, even the few exceptions to no glaciation without low CO2 found by Royer have been found, with higher resolution data, to not be exceptions (although in some cases the interpretation of the data is still in dispute). Richard Alley gave an excellent presentation of the current information at the 2009 Fall meeting of the AGU.
If I were to use a "take home message" for undergraduate non science majors, I gather the message from DSL is:
"Although CO2 is a key factor in controlling the climate, it would be a mistake to think it's the only factor"
Whereas the message from Richard Alley would seem to be that, if one takes the most recent results into account, the CO2 level is, if not the only factor, surely the dominant factor.
Welcome to Skeptical Science,
As you thought, there has been a lot of discussion of nuclear power and a variety of opinions expressed. You should use the search button in the upper left corner to locate the threads you are interested in. My favorite is the thread on renewable baseload power, where nuclear was often discussed. This is a hot button issue and you are likely to see lot of difference of opinion. If you have substantial references to contribute the discussion will be better than if you just state your opinion.
At 211, why do you suggest the two options are different? CO2 is the dominant factor, but there are a number of other factors, especially on a short term basis.
Where CO2 is concerned, look at three papers:
1. Foster & Rahmstorf (2011) (discussed here by one of the authors), which removes solar, volcanic, and ENSO effects from the recent surface temp record to see what sort of trend might be left over.
2. Lacis et al. (2010) or Schmidt et al. (2010), which discuss the role of CO2 as the primary "control knob" of climate.
3. Puckrin et al. (2004), which compares modeled and observed radiative flux for various GHGs, including water vapor.
Any further responses on the subject of "CO2 was higher in the past" really do need to go here. As for CO2 being the driver of climate, responses should go here. Any responses will be seen, since many (most?) of the regular posters check the recent comments thread regularly.
Here is the posters question, any advice would be appreciated.
"A couple of years ago I surveyed some of the scientific literature on global warming. (The actual scientific literature, not the NYT Science Column or something of that nature.)
Now, we know that the earth warms and cools in natural cycles, and the question is "Has human activity been speeding up the warming, and has it done so to such an extent that it will overpower those natural cycles and create a run-away greenhouse effect?"
The atmosphere is about 360ppm, that's parts-per-million, carbon dioxide. Due to human activity, this number is increasing by about 1-2 ppm per year. Over 90% of that increase is from industrial processes, and less than 10% is from the day-to-day activities of people, such as driving cars. So we would have to devastate industrial production, including agriculture and electrical generation to make a dent in that 1-2 ppm increase per year.
Now, here is my question. Can you cite me some scientific literaure that would support the idea that a 1-2 parts-per-million increase in carbon dioxide would have a significant impact on the thermodynamic properties of the atmosphere?
I don't want to hear "but all the scientists who receive large grants from the EPA agree", I want an actual reference to something published in a peer-reviewed journal that would support that statement about the thermodynamic properties of the atmosphere. Will you (or anyone else) please send me that information?"
Thoughts? Or peer-reviewed articles which address this topic?
Some good graphics extracted from a couple of papers and you can follow the research references from both the Intermediate and the Advanced versions. There's also the Intermediate version of Myth 33
Have a look at the whole list of Climate Myths and see if you can spot others that might give leads to the sort of thing that could help you.
The effect of GHG on the radiative properties of the atmosphere has been known since Arrhenius, but the foundational physics can found in Ramanathan and Coakley 1978. Note that the model applies to any rotating planet not just earth.
[Source]
Additionally consider that the range of atmospheric CO2 from glacial to interglacial is about 100 ppm, which corresponds to a temperature range of 6ºC. This factors in time for the system to reach temperature equilibria with the CO2 forcings.
What is different now from previous interglacials is the injection of previously-sequestered CO2 back into the carbon cycle sufficient to raise global atmospheric CO2 levels by more than 100 ppm. And that this rise began with CO2 already at CO2 interglacial apex...
This is all documented on this website on many, many threads of the more than 4,000 threads that exist here. All with links to the published, peer-reviewed literature.
The Search function is your friend, and doorway to learning, at Skeptical Science.
We have embarked on a journey to a climate last seen in the Miocene or Pliocene, with no possibility of return to the preindustrial, stable, climate that saw the rise of agriculture and civilization:
[Please note that while most links are to Skeptical Science articles, virtually all include multiple references to peer-reviewed literature. But you're not going to understand the answer very often by taking one, single paper in isolation. Science is the body of work, as it is (well) understood by the people who do it every day. So you need the Skeptical Science articles to help provide introduction and context where you may be lacking in background knowledge.
But Skeptical Science articles are very heavily cross-linked to supporting material. Follow the links.]
There are so many fallacies in what you posted, both in the argument that you presented and the way the components that you posted, that I don't know where to begin. I will remember that your main question was on that puny 1-2 ppm CO2, but:This is the first "gotcha" that implies that (a) climate changes a lot (it doesn't) and (b) we don't understand those magical, mystical cycles. Both implications are dead wrong.
Internal Variability
It's a Natural CycleThis is like asking if you are still beating your wife. How do you answer? Human activity is not speeding up warming, it is causing warming. Without human activity the planet would be cooling right now. Solar activity is down, dimming aerosols are up.
Lean and Rind (2008)
Gillett et all (2012)
It's not the sunThis is denial-alarmism for a you, a strawman created to make the opposing position look ridiculous, by exaggerating it to the point where it is ridiculous. No one is saying there will be a run-away greenhouse effect. No one has to. A plain, ordinary 3˚C to 5˚C of warming can be catastrophic to civilization and people, all by itself. It won't be a runaway effect, but it can be very bad.
Runaway Warming
VenusIndustrial processes that do what? Make cars, televisions, and plastic toys? Make ships and trucks and airplanes that move the cars, televisions and plastic toys? This is another strawman, making any effort to separate what you use individually. You are a member of society, a complex, interwoven, technological-industrial society. You use everything society creates, and that includes the tanks and the planes that guard your borders, even if you never sit in them yourself.More denial alarmism. The only people who say that taking immediate, deliberate action will devestate economies are denial-alarmists, who are trying to frighten you away from thinking clearly.
CO2 Limits Economy
Renewable EnergyFirst, this contains yet another debate-tactic, the implication that human contributions are so small on an annual basis that it can't possibly matter.
CO2 is Just a Trace Gas
But what really matters isn't the 1-2 parts-per-million per year, it's the 337 gigatons that mankind has added (split between the atmosphere and the ocean, which is another huge, huge problem all by itself). That raises CO2 from 285 ppm to currently 400 ppm. That's not 1-2, that's 115. That's not a small percentage, that's a %40 increase.
"A significant impact on the thermodynamic properties of the atmosphere?"
The question you are asking is covered by the body of scientific literature on the subject. No, scientists didn't write one nice, neat paper to explain it to your friend because they thought he might ask. They've written hundreds of thousands of papers, discussing various details including everything from climate sensitivity to radiative properties.
In that light, I think that your question is best answered by reading (sorry, it's long, but really, it's necessary) Spencer Weart's The Discovery of Global Warming. This will tell you, in a rather easy to read format (given how dry the subject matter can be) how science developed, from the beginning to the near present, to the point where we understand fairly well (and continue to improve our knowledge, in spite of denial attempts to interfere with science and keep us in the dark):
So... I'm sorry that the bottom line answer to your question is not "Hansen et al (2004) Everything Anyone Wants to Know About Climate Change in An Easy, 5 Page Peer Reviewed Paper." That's never going to happen.
But everything your friend said, including the things he falsely implied, is easily answered. The information is there, and the falsehoods need to stop. If deniers want to argue about things, let them argue about real things, not made-up strawman arguments intended to frighten people away from thinking clearly.
I ended up providing the questioner with a link to the National Research Council's "Climate Change Science" Report
I then added this,
"Here is a quote from the report which I provided a link for, which addresses some of the points which you brought up in your post.
"That the burning of fossil fuels is a major cause of the CO2 increase is evidenced by the concomitant decreases in the relative abundance of both the stable and radioactive carbon isotopes and the decrease in atmospheric oxygen. Continuous high-precision measurements have been made of its atmospheric concentrations only since 1958, and by the year 2000 the concentrations had increased 17% from 315 parts per million by volume (ppmv) to 370 ppmv. While the year-to-year increase varies, the average annual increase of 1.5 ppmv/year over the past two decades is slightly greater than during the 1960s and 1970s."
The key for me is the fact that while an increase of 1 to 2 ppm/yr. by itself would not raise temperatures greatly, the cumulative increase over time would begin to raise Earth's temperatures and cause greater issues. An increase of 55 ppm from 1958 to the time of the writing of this report is more significant and concerning. If these numbers continue increasing at the current rate of 1 to 2 ppm/yr. by 2058 the ppm levels of CO2 in the atmosphere will be between 415 ppm (low end) and 515 ppm (high end). (I did those numbers in my head as I was typing this so they might be off a little but I am pretty sure they are right). So, the increase in a one hundred year period between 1958 and 2058 would be 31.7% (low end) and 63.49% (high end). Now we are starting to get into areas of greater concern than simply stating that the increase is simply 1 to 2 ppm/yr."
Thank you all for this site and for the information which you have provided me so far. :)
Brent McCay
The key point you should take is probably that which Dan Bailey gave you, that CO2 levels are now at a point which has not been reached in 800,000 years, and the climate that went with higher CO2 levels was frightening.
If you are taken to task on that, I'd point you towards my own post, (Fahrenheit) 451 ppm for a few different perspectives on just what 451 ppm of CO2 could mean.
If you are taken to task for the source of CO2 in the atmosphere (your last post implied as much, even though your original post did not suggest it), that is the easiest thing in the world to refute, and anyone who clings to that position is in absolute, complete denial.
CO2 Increase is Natural
[There are lots and lots of other links on that, but I think that one gives the best overall summary of all of the various lines that put a nail in any idea that CO2 could come from anywhere but fossil fuels (and if it were... where the heck did the 337 gigatons of fossil fuel CO2 go to?).]
I have a question that necessitates showing a scientific graph. Is there a way I can make such a graph visible to others?
-a href="http://page_url"--img src="http://image_url" alt="" width="450" /--/a-
with the "-" being replaced by greater than and less than symbols as appropriate.
I have been deep into contacting, and reviewing various kinds of solar charities/offsets and found a lot of interesting things. But to do this right is going to take a while. There are complications. For instance, say you have two efforts that were equivalent otherwise, but one was in a population that had a high growth rate within a forested area and another was in a stable population. It might be argued that for the rapidly growing population, improved birth control would be the better choice for a contribution and in the stable population case, the solar offset would be better.
Have emails for new blog post been discontinued? The last one I have received was back on July 8, 2012. According to SkS, I'm still set up to receive emails from SkS. I have no filter set up for email. Nothing for some time, though.
TIA,
koyaanisqatsi
CuriousD back. Not sure where to post this but as a pretty much still Newbie this is probaly an o.k. place. Just realized:
1. Looked at the Berkeley Earth Surface Temperature (BEST) web site and they get 1.5 degrees C increase over 250 years. Then since 40% increase since industrial revolution in CO2
one has C2/C1 = 1.4 = 2^(t1/3) assuming 3 degreeC C.S. Solving, indeed t1 = 1.5 degrees.
2. And from 1980 (Keeling Curve) to present, CO2 increased so that C2/C1 ~ 400/340 = 1.2= 2^(t2/3)
Solving, t2 = 0.75 degrees. Neato Mosquito , hey?
I just came across a suggestion when I searched under my name that I should apologize to John Cook for saying something about him being too busy to respond to a question I had. Believe me, I never meant to say anything negative about John, who is doing great and valuable work by creating this website. I apologize profusely, although I am still not sure what I did wrong here.
This website has changed my life in a good way, and allowed me to become active in the war for climate truth and action. Am I in the good graces of SKS? If not is there a way to further make amends?
Link to the paper is here: http://www.warwickhughes.com/climate/karner.pdf
It's from 2002 and appears to have been published in the Journal of Geophysical Research. I tried to review the paper, but it's outside of my knowledge box :).
Anyone have any comments or debunking advice on this?
Tamino: I note that Kärner gives props to McKitrick for his advice. An economist...
I have a question. I read somewhere about a possible Venus effect with Earth's global warming. The writer posited that Venus' Runaway global warming hypothosis created Venus's atmosphere as it is today and could be a possibility for Earth if it succumbs to runaway global warming. The writer went on to say that the artic melt would allow large quantities of methane to be released into the atmosphere as well as acidification and warming of oceans would cause phytoplankton to die off and thereby the absorption of CO2 by the phytoplankton would cease or be greatly reduced and these along with other factors would cause Earth's atmosphere to become like Venus'. Is this scenario plausable?
gaiafollower @234, a Venus like runaway greenhouse effect is not currently possible on Earth based on the best evidence to date. That is, the Earth's oceans will not boil away, and cannot be made to boil away simply by adding CO2 (and/or methane) to the atmosphere; although in several billion years they will boil away due to the Sun getting hotter with time.
On the other hand, it is perfectly possible that feedbacks from anthropogenic CO2 could result in feedbacks resulting in an increase in temperature of 10 plus degrees C, a situation that will make parts of the Earth literally uninhabitable due to heat. Those scenarios are not plausible, however, in the short term. Only when temperatures start reaching 4-5 C above current levels will further increases plausibly push us into that sort of feedback regime.