While I was blogging over the past few weeks about fact-checking George Will’s dismissal of global warming (collected here), I got comments. A lot of them.
A fair number of commenters claimed George Will was right, and presented evidence that they claimed supported him. Some tried to back their claims with news that came out after Will’s column was published. For example, a few days after his column came out, there were reports that the a satellite that measure ice cover had some trouble and was fixed. But George Will could not jump forward in time, check out the satellites, and then leap back to write his column. There’s no way that it could have any bearing on fact-checking his piece. What’s more, even if Will did know about them, he’d still be wrong, as I explained here.
Today brought more time-travel. Trey writes:
Just FYI to the AGW crown [sic] and to support George Will and Lou Dobbs (CNN) there appears to be a shift to global cooling now. MSNBC and Discovery.com are reporting no warming since 2001 and that we’re looking at no warming or even cooling for the next several decades.
http://dsc.discovery.com/news/2009/03/02/global-warming-pause-02.html
http://www.msnbc.msn.com/id/29469287/
My response is much the same as my response to the satellite story. On February 15, George Will wrote the following about current “global cooling”:
Besides, according to the U.N. World Meteorological Organization, there has been no recorded global warming for more than a decade.
If we’re going to fact-check George Will, this is what we have to check. What does the World Meteorlogical Organization in fact have to say about global warming?
This (from April 2008):
The long-term upward trend of global warming, mostly driven by greenhouse gas emissions, is continuing. Global temperatures in 2008 are expected to be above the long-term average. The decade from 1998 to 2007 has been the warmest on record, and the global average surface temperature has risen by 0.74C since the beginning of the 20th Century.
And this (from May 29 last year):
While important uncertainties still remain, the overwhelming global scientific consensus, as reflected through the IPCC Fourth Assessment Report, is now that the Earth’s atmosphere is warming at an increasing rate and that most of this warming is very probably due to human activities, particularly fossil fuel burning and certain agricultural practices. It is also recognized that, while these changes are just beginning, their impacts will intensify in the coming decades.
If George Will has been having back-room chats with the World Meteorological Organization folks, where they’ve repudiated statements like these, he hasn’t share that news with the rest of us. My hunch is that Will would point to 1998, which was a very warm year, and say, “See, global warming stopped in 1998.”
But that’s not how the World Meteorological Organization (or any major organization of climate scientists) judges global warming. It’s pointless to pick out a single year for comparison, because the rising global temperature trend is overlaid on a naturally variable climate. If Will decided to pick 1997 or 1999, he’d have to deal with a year that was cooler than recent years. In fact, the World Meteorological Organization judges global warming based on averages of several years, which they compare to the entire climate record since humans started pumping carbon dioxide into the atmosphere on an industrial scale.
So what about this new report from Discovery.com, and reprinted by MSNBC? First off, a fact-checker can’t use it to confirm a statement Will made about the World Meteorological Organization three weeks ago. The story itself from Discovery is very short and doesn’t provide any details about where the study in question came out. So I got in touch with the scientists, Kyle Swanson and Anstasio Tsonis of the University of Wisconsin. They sent me their paper, called “Has the climate recently shifted?” It will be published soon in Geophysical Research Letters.
Swanson and Tsonis observe that over the past century, the average global temperature has risen, but there have been periods when it has dropped temporarily. Swanson and Tsonis have been investigating how the natural climate variability may explain the shifts between these phases. This variability includes oscillations in the circulation of the ocean and the air. El Nino is the most famous of these oscillations, but there are others as well in the North Pacific and the North Atlantic. Only three times in the twentieth century did all these oscillations synchronize, after which the climate moved to a new state. This figure, from the paper, shows the periods of synchronization as cross-hatched bars.
Based on the study of chaotic systems, Swanson and Tsonis propose that the synchronization and climate shift are connected through cause and effect. Once a lot of oscillations are working in sync, even a small change to one of them can radiate out through the whole system and trigger a change. And along with the three shifts in the real climate, climate models also show a similar response when oscillations line up.
In their paper, Swanson and Tsonis then look at the past few years. They see a peak in synchronization in 2001 and 2002, and they also observe that in the years since, the temperature change has been on average flat (although much warmer than at the beginning of the century). They estimate that all the warming due to carbon dioxide should have driven the temperature up .25 degrees C since then. The fact that it hasn’t leads them to propose the the oceans and atmosphere have changed the way they handle heat. The oceans may have absorbed more heat due to a change in circulation, or the atmosphere may radiate more heat away by clouds. If this hypothesis is true, then it’s possible that the climate will remain in this new stage for some years to come before it shifts again.
Swanson and Tsonis write:
Of course, it is purely speculative to presume that the global mean temperature will remain near current levels for such an extended period of time. Moreover, we caution that the shifts described here are presumably superimposed upon a long term warming trend due to anthropogenic forcing.
They conclude with this warning:
Finally, it is vital to note that there is no comfort to be gained by having a climate with a significant degree of internal variability, even if it results in a near-term cessation of global warming. It is straightforward to argue that a climate with significant internal variability is a climate that is very sensitive to applied anthropogenic radiative anomalies (c.f. Roe [2009]). If the role of internal variability in the climate system is as large as this analysis would seem to suggest, warming over the 21st century may well be larger than that predicted by the current generation of models, given the propensity of those models to underestimate climate internal variability [Kravtsov and Spannagle 2008].
This story has been bouncing around a lot around the blogosphere. The conservative Heritage Foundation quoted from the Discovery.com piece with the headline, “Trillions in New Taxes to Accomplish Nothing.” A lot of the coverage describes the study as showing that global warming stopped in 2001, as Trey writes. But the paper doesn’t say that. It says that a synchronization happened then. It’s a bit odd how easily people can shift from claiming the warm year of 1998 as the end of global warming to 2001.
So I asked Swanson and Tsonis what they thought about its reception.
Tsonis wrote,
I was worried that this will happen, that is why we caution in the paper that while climate shifts may be part of the natural variability of the climate system they may be superimposed on a anthropogenic warming trend. We mentioned that also in the MSNBC story, and this will be my answer to anybody who asks me.
I like to report on the science only. If political organizations want to pick up what they like in order to pass their point and ignore the real science, there is nothing we can do.
Swanson wrote to me that this natural shifting is exactly what you’d expect if the Earth’s climate was indeed sensitive enough to carbon dioxide that it would respond by warming as has been projected.
We are describing in this paper what is generally referred to as “internal” (natural) climate variability, superimposed upon a robust global warming trend at century time-scales. Viewed in that light, the “halt” in global warming is no different than an El Nino/La Nina transition, which also breaks a warming trend – what we are describing is just climate variability that occurs over longer time scales.
Swanson and Tsonis have certainly come up with an intriguing hypothesis, based both on temperature observations and mathematical models of the climate. I’ll be curious to hear what other climate scientists think of it. It will take time to test, but even if it turns out to be right, it does not mean that global warming is over. If George Will could have climbed into a time travel machine and jumped forward to today, he would have been wrong if he tried to use this study to bolster his arguments back in February.
Update: I just noticed the Discovery news article did mention the journal where the paper will be published. I’ve struck the offending text.
March 4th, 2009 at 3:22 pm
The Swanson and Tsonis paper sounds interesting and is, of course, something for climate scientists to debate. Discovery.com was a little sloppy with their coverage, in my opinion. To start with, the title is somewhat sensationalistic, “Global Warming: On Hold?” Then, the first sentence talks about the ‘cooling mystery’. What cooling? There hasn’t been a cooling spell long enough to say we are on a downward trend.
March 4th, 2009 at 4:53 pm
Isn’t part of the “fact checking” problem using MSNBC and discovery.com as sources? These are not primary sources, and not really secondary sources. They both are popular media. A secondary source might be a review article in a professional journal. A good solid secondary source should be authored by a professional in the field.
From where I stand, the entire global warming debate has been confused by professional versus journalistic coverage. In my view, it’s fine for journalists to write about global warming. But these articles should never be the source material for other articles, or even for an individual to change his or her opinion. That’s just sloppy. How hard is it for other journalists to contact scientists or original sources? How hard is it for an individual, who reads a provocative journalistic article on a subject, to look for professional reaction to the article?
While it is OK for a professional to re-interpret another scientist’s data, its highly questionable for a non-professional to do the same. Professional training means something. Typically, professional training takes about 10 years. But the way the global warming issue is framed, all opinions are equal, and anybody can make any weird theory, interpreting data however they choose.
In the original Will article, he picked some points off a scientific graph and made his own interpretation. Part of the issue is that he cherry picked. But equally egregious is that he never asked a professional if his interpretation would make any sense to a professional in the field. What Will’s fact checkers appear to have done is to look at the same graph and see if they – non professionals – could support Will’s interpretation. As Carl pointed out, they never asked the authors, or, apparently, any other professional, whether their graph reading would pass muster.
March 4th, 2009 at 10:45 pm
Thorn is right about the reporting. The article has everything from “cooling” (displaying a picture of a March snowstorm as evidence) to warming “on hold” to warming “slow down”.
Swanson’s comment here struck me as odd, referring to the 2001-2008 period:
“Swanson said the overall trend is flat, even though temperatures should have gone up by 0.2 degrees Centigrade”
Hmmm… 0.2 C in 7 years? Is that what was projected in the absence of other factors? I thought the average model wasn’t any more than 0.2 C per decade in the near future – not 7 years. Also, this seems to ignore the downside of the solar cycle, now at an extended minimum. This would seem to shave a bit off the trend. There was also a fairly strong la Nina in 2008 and a flattening of methane emissions. This leads me to believe they are over-emphasizing the internal variability in the study.
[Markb: Here's the relevant passage from the paper--"It has been hypothesized that the planetary radiative budget in recent decades has been out of balance due to radiative forcing by greenhouse gasses and lags in the oceanic response, with absorption exceeding emission by roughly 0.8 Wm−2 around the turn of the century [Hansen et al. 2005]. Since then, by itself increasing CO2 concentrations of roughly 20ppm should have further added roughly 0.2 Wm−2 to this top-of-the-atmosphere excess of absorption over emission. Assuming a mixed layer ocean depth of 200 m, an anomaly of roughly 1 Wm−2 should in principle have been sufficient to drive roughly a 0.25◦ C increase in global temperature since 2001/02.” ]
March 4th, 2009 at 11:28 pm
They still seem to be picking a higher forcing estimate during this time period than the mean from the average climate model. Some models actually show cooling during an 8-year span.
http://www.realclimate.org/index.php/archives/2008/05/what-the-ipcc-models-really-say/
Is their estimate of CO2-forced temperature change used as a variable in their study?
March 4th, 2009 at 11:44 pm
FYI…I re-checked the Discovery.com article, and it has been significantly changed from yesterday. Originally, there was no indication which journal would report the study–I re-read it a few times, to be sure. Also, the opening statement no longer contains the ‘mystery cooling’ I referred to, in my previous comment. Just wanted to clear up any confusion.
[Carl: Yeah, I think they updated the piece without telling us.]
March 5th, 2009 at 8:01 am
[...] laid off the on-going saga of George Will versus Reality, but Carl Zimmer really takes him and global warming denialism to school. Does a good job of tackling the new [...]
March 5th, 2009 at 11:34 am
It is always nice to see articles by real professional science writers like Mr. Zimmer and Mr. Mooney who actually have some knowledge of the subject matter. As opposed to dilettantes like Lou Dobbs and George Will who don’t know their posteriors from an excavation.
March 5th, 2009 at 11:55 am
[...] material under the slogan The George Wil on Ice Affair. The latest (as of 4 March) post is Checking George Will: The Perils of Time Travel: A fair number of commenters claimed George Will was right, and presented evidence that they [...]
March 6th, 2009 at 2:23 am
Your not convincing. The science has to leak out between the lies and the threats from the global warming thugs.
Each of the scientists responds to inquiries with tepid remarks that their remarks, facts, reports, have been abused; that indeed there is a global warming trend absolutely, or probably, caused by human activity.
All your diatribe does here is make it clear the entire scientific community understands the threat they are under from thugs like you.
Unfortunately for you, nature is not intimidated and we have entered a cooling period. It will have to become overwhelming before you lunitics will give your lies, but, just as the acid rain hoaxed passed, so will the global warming hoax.
[Carl: "All your diatribe does here is make it clear the entire scientific community understands the threat they are under from thugs like you." Can you show me the names of scientists I have threatened in these posts? The only people I have been criticizing in them are George Will, his editors, and others who write about global warming. I have consulted with several climate scientists about their own research, and I have quoted them at length. Where is the thuggery?]
March 6th, 2009 at 10:10 am
Re Sunshine
It will have to become overwhelming before you lunitics will give your lies, but, just as the acid rain hoaxed passed, so will the global warming hoax.
Gee, are these hoaxes like the HIV/AIDS hoax, the cigarette smoking/lung cancer hoax, the Holocaust hoax, the CFCs/ozone depletion hoax, the moon landing hoax? End snark.
March 6th, 2009 at 10:40 am
“…but, just as the acid rain hoaxed passed, so will the global warming hoax.”
The “acid rain hoax”?
Are you actually tyring to claim that because the regulation of specific sulfur- and nitrogen-based industrial waste products has worked to reduce acid rain in the US that the whole thing was a hoax?
You should tell that to Eastern Europe, China, and Southeast Asia; they’ll be delighted to hear that the acid rain they’re still getting hit with is just a “hoax.”
March 6th, 2009 at 3:08 pm
I just wanted to post to thank you for all of your time spent fact-checking and investigating, Carl. This is a tough subject to keep up with(I’m certainly too engrossed in my own studies to do so), and your striving to maintain scientific accuracy does not go unnoticed. Both the scientific community and the general public need writers like you.
Thank you.
March 6th, 2009 at 9:56 pm
Just to shine, what I hope is, a light of reality upon these proceedings. It has been my observation that the nay-sayers of any well-established theory have a sharp, clear agenda. They start with the result (which is Right and Beyond Question) and they go around looking for any evidence, no matter how thin or implausible, to back them up.
This is not science, even though it has a wafer thin resemblance to the scientfic method. A scientist goes where the data takes them. Any idea can be overturned or amended, given enough evidence.
The political deniers will not be swayed by evidence. They seize upon the supporting evidence and totally discount contradicting evidence.
Go ahead and debate away. Use your scientific methods and instincts. Just remember that only scientifically minded people will give you a fair hearing. The deniers are playing a political game, and can only be defeated politically.
March 6th, 2009 at 10:32 pm
Fact Check:
The WMO states that: “Global temperatures in 2008 are expected to be above the long-term average. The decade from 1998 to 2007 has been the warmest on record, and the global average surface temperature has risen by 0.74C since the beginning of the 20th Century.” None of these statements contradicts Will’s claim that there has been no “recorded” warming in a decade. They essentially dodge the issue of the recent trend. Will addresses that trend, not the consistently high values over that time. Nor do these statements by themselves support the WMO’s opening sentence, “The long-term upward trend of global warming, mostly driven by greenhouse gas emissions, is continuing,” at least, not over the most recent decade.
The WMO states that: “While important uncertainties still remain, the overwhelming global scientific consensus, as reflected through the IPCC Fourth Assessment Report, is now that the Earth’s atmosphere is warming at an increasing rate and that most of this warming is very probably due to human activities, particularly fossil fuel burning and certain agricultural practices. It is also recognized that, while these changes are just beginning, their impacts will intensify in the coming decades.”
This represents a scientific consensus on future expectations. As such it does not contradict Will’s claim regarding “recorded” warming over the last decade. Will, like many of his ilk, is exploiting the acknowledged fact that with the extraordinary El Nino year of 1998 and natural climate variations since then, there has been little net warming over the past decade. This is supported by WMO statistics. A qualified fact checker would find Will’s statement to be essentially correct. The point is, it’s highly misleading. Unfortunately, there’s no easy way to counter that observation, except by waiting for the long-term background trend to resume its march upward. And that could be some years away.
Tom
March 9th, 2009 at 4:52 pm
[...] then invokes a new paper which I wrote about last week on a potential new shift in the climate. “In a new study, University of [...]
April 2nd, 2009 at 11:36 am
[...] Checking George Will: The Perils of Time Travel [...]
April 3rd, 2009 at 1:59 am
[...] Checking George Will: The Perils of Time Travel [...]
April 7th, 2009 at 3:55 pm
[...] Will appears to have borrowed this nugget from climate change skeptic web sites, which have elevated the argument that global warming has stopped or reversed to the status of an Internet ‘meme.’ However, it has been debunked time and again“ [...]
April 7th, 2009 at 5:22 pm
[...] Will appears to have borrowed this nugget from climate change skeptic web sites, which have elevated the argument that global warming has stopped or reversed to the status of an Internet ‘meme.’ However, it has been debunked time and again. [...]
June 12th, 2009 at 6:03 pm
Al Gore meet Peabody and Sherman SO MR PEABODY STICK AL GORE IN THE WAYBAC MACHINE HERMAN SETS IT FOR THE YEAR 1547 AND GORE FINDS HIMSELF IN THE MIDDLE OF EUROPR DURING THE BLACK DEATH CUASED BY RATS AND FLEAS
September 28th, 2009 at 12:36 pm
[...] Originally Posted by Anastasios Tsonis I was worried that this will happen, that is why we caution in the paper that while climate shifts may be part of the natural variability of the climate system they may be superimposed on a anthropogenic warming trend. We mentioned that also in the MSNBC story, and this will be my answer to anybody who asks me. I like to report on the science only. If political organizations want to pick up what they like in order to pass their point and ignore the real science, there is nothing we can do. http://www.uwm.edu/~kswanson/publica…037022_all.pdf RealClimate: Warming, interrupted: Much ado about natural variability Checking George Will: The Perils of Time Travel | The Loom | Discover Magazine [...]