UPDATE: Dr. Roger Pielke Sr. has a comment on the paper here: Comments On The Dessler 2011 GRL Paper “Cloud Variations And The Earth’s Energy Budget also, physicist Lubos Motl has an analysis here. The press release from TAMU/Dessler has been pushed to media outlets on Eurekalert, see update below.
UPDATE2: Dessler has made a video on the paper see it here And Steve McIntyre has his take on it with The stone in Trenberth’s shoe
I’ve been given an advance copy, for which I’ve posted excerpts below. This paper appears to have been made ready in record time, with a turnaround from submission to acceptance and publication of about six weeks based on the July 26th publication date of the original Spencer and Braswell paper. We should all be so lucky to have expedited peer review service. PeerEx maybe, something like FedEx? Compare that to the two years it took to get Lindzen and Choi out the door. Or how about the WUWT story: “Science has been sitting on his [Spencer’s] critique of Dessler’s paper for months”.
If anyone needs a clear, concise, and irrefutable example of how peer review in climate science is biased for the consensus and against skeptics, this is it.
I’m sure some thorough examination will determine if the maxim “haste makes waste” applies here for Dessler’s turbo treatise.
Cloud variations and the Earth’s energy budget
A.E. Dessler
Dept. of Atmospheric Sciences
Texas A&M University
College Station, TX
Abstract: The question of whether clouds are the cause of surface temperature changes, rather than acting as a feedback in response to those temperature changes, is explored using data obtained between 2000 and 2010. An energy budget calculation shows that the energy trapped by clouds accounts for little of the observed climate variations. And observations of the lagged response of top-of-atmosphere (TOA) energy fluxes to surface temperature variations are not evidence that clouds are causing climate change.
Introduction
The usual way to think about clouds in the climate system is that they are a feedback — as the climate warms, clouds change in response and either amplify (positive cloud feedback) or ameliorate (negative cloud feedback) the initial change [e.g., Stephens, 2005]. In recent papers, Lindzen and Choi [2011, hereafter LC11] and Spencer and Braswell [2011, hereafter SB11] have argued that reality is reversed: clouds are the cause of, and not a feedback on, changes in surface temperature. If this claim is correct, then significant revisions to climate science may be required.
…
Conclusions
These calculations show that clouds did not cause significant climate change over the last decade (over the decades or centuries relevant for long-term climate change, on the other hand, clouds can indeed cause significant warming). Rather, the evolution of the surface and atmosphere during ENSO variations are dominated by oceanic heat transport. This means in turn that regressions of TOA fluxes vs. ΔTs can be used to accurately estimate climate sensitivity or the magnitude of climate feedbacks. In addition, observations presented by LC11 and SB11 are not in fundamental disagreement with mainstream climate models, nor do they provide evidence that clouds are causing climate change. Suggestions that significant revisions to mainstream climate science are required are therefore not supported.
Acknowledgments: This work was supported by NSF grant AGS-1012665 to Texas A&M University. I thank A. Evan, J. Fasullo, D. Murphy, K. Trenberth, M. Zelinka, and A.J. Dessler for useful comments.
h/t to Marc Hendrickx
=============================================================
UPDATE: Here is the press release from Texas A&M via Eurekalert:
Texas A&M prof says study shows that clouds don’t cause climate change
COLLEGE STATION, Sept. 6, 2011 — Clouds only amplify climate change, says a Texas A&M University professor in a study that rebuts recent claims that clouds are actually the root cause of climate change.
Andrew Dessler, a Texas A&M atmospheric sciences professor considered one of the nation’s experts on climate variations, says decades of data support the mainstream and long-held view that clouds are primarily acting as a so-called “feedback” that amplifies warming from human activity. His work is published today in the American Geophysical Union’s peer-reviewed journal Geophysical Research Letters.
Dessler studied El Niño and La Niña cycles over the past 10 years and calculated the Earth’s “energy budget” over this time. El Nino and La Nina are cyclical events, roughly every five years, when waters in the central Pacific Ocean tend to get warmer or colder. These changes have a huge impact on much of the world’s weather systems for months or even years.
Dessler found that clouds played a very small role in initiating these climate variations — in agreement, he says, with mainstream climate science and in direct opposition to some previous claims.
“The bottom line is that clouds have not replaced humans as the cause of the recent warming the Earth is experiencing,” Dessler says.
Texas is currently in one of the worst droughts in the state’s history, and most scientists believe it is a direct result of La Niña conditions that have lingered in the Pacific Ocean for many months.
Dessler adds, “Over a century, however, clouds can indeed play an important role amplifying climate change.”
“I hope my analysis puts an end to this claim that clouds are causing climate change,” he adds.
For more information about Dessler’s research, go to http://goo.gl/zFJmt
About Research at Texas A&M University:
As one of the world’s leading research institutions, Texas A&M is in the vanguard in making significant contributions to the storehouse of knowledge, including that of science and technology. Research conducted at Texas A&M represents an annual investment of more than $630 million, which ranks third nationally for universities without a medical school, and underwrites approximately 3,500 sponsored projects. That research creates new knowledge that provides basic, fundamental and applied contributions resulting in many cases in economic benefits to the state, nation and world.
Not to defend Leif, but what you are doing here is the same thing the warmists do.
1) Fact: Earth is warming
2) Fact: CO2 Concentration is increasing
3) Prove to me they’re not inter–related.
You are shifting the burden of proof away from where it should reside. You are taking the first step there into creating an alternate dogma which says that only the sun can alter the climate. Admittedly that’s not as strange a concept at least, but it’s still a dogma. The burden of proof resides with those who make an assertion, regardless of what circumstantial evidence exists. It must always reside there.
Mervyn Sullivan says:
September 7, 2011 at 5:49 am
I refer to the comment “If anyone needs a clear, concise, and irrefutable example of how peer review in climate science is biased for the consensus and against skeptics…”.
Shouldn’t that be “… irrefutable example of how peer review in climate science is corrupt”?
So, tell again me why M. Mann needs an attorney to protect his “6?” Could it be the corruption is deeply and significantly entrenched? The entire process has become criminal. I imagine the greatest fraud in modern time money train could be in jeopardy
Does anyone think there would be an interest now in a tool to estimate historic cloud cover globally? Last time I asked (about 4 years ago) there were no dollars left in the pot.
Phil Jones famously said:
Kevin and I will keep them out somehow – even if we have to redefine what the peer-review literature is!” – Phil Jones 8/7/2004
tallbloke says:
September 7, 2011 at 7:21 am
The fact is the sun in the past 50 years has been more active than anytime in past 400 years. It’s called the modern maximum. You aren’t entitled to deny that fact.
As Mark Twain said “it is not what you know that get you into trouble, it is what you know that just ain’t so”.
Solar activity in parts of the 18th century was higher than in the past 50 years. The ‘Modern Grand Maximum” is mostly caused by the introduction of the weighted sunspot count in the middle of the 20th century [which by itself artificially increases the sunspot number by 20%].
tallbloke says:
September 7, 2011 at 7:21 am
The fact is the sun in the past 50 years has been more active than anytime in past 400 years.
Fact: “Recent 10Be values are low; however, they do not indicate unusually high recent solar activity compared to the last 600 years.”
http://www.leif.org/EOS/2009GL038004-Berggren.pdf
I think I have pointed this out to you several times.
Dressler11 may have shown, instead, that there is no relationship between surface temperature and cloud forcing (at least for the period in question and for the data sets analyzed). That result should flow from the r2 reported by Steve McIntyre for the correlation between these two variables that is virtually zero: 0.01045 (i.e. only about 1% of the cloud forcing can be explained by surface temperature). AR4 states in Section 8.6.2.3:
So, Dressler11 contradicts the positive cloud feedback predicted by the models, on the grounds that it is necessary to establish that there is an actual relationship (i.e. an r2 larger than 0.5), before one should be able to claim scientifically what the sign and magnitude of the relationship is. It would follow then that the proposed cloud forcing would be an independent variable (i.e. independent from CO2*). That would change CAGW theory significantly.
*CAGW theory says that surface temperature is a variable dependent on CO2, so, if cloud forcing is independent from surface temperature, it would then also be independent from CO2.
Myrrh says:
September 7, 2011 at 3:08 am
Thanks for your comment. Please stay with us here at WUWT. I have been a compulsive ‘lurker’ here as well as several other sources of info re: climate issues. I have learned a lot. I have also gotten lost in some of the various arguments presented. I believe that this was possibly a result of my keeping an open mind and ultimately polluting it to some degree (confusion) with too much sorting of info (mental overload?).
The issues that you put forth in the above post correlates with my basic understanding (light and infrared) learned years ago. Please help keep me on track with the basic physics so as I can maintain my confidence in an objective evaluation of the current issues. I will admit that I am very skeptical with regards to sources that I accept with great confidence, but you have caught my attention. With regards to any discussion that you may offer, I will “trust but verify”. I appologize somewhat with that statement, but I ‘gotta be sure’.
Over the past couple of years I have become quite skeptical of the arguments that have been put forth by the CAGW crowd and the lack of transparency and obvious gatekeeping tactics they have employed. Toss in the political spectrum and I am very alarmed.
Many arguments seem to focus on fine details, and necessarily so. But I, while able to follow those, am trying to view issues from a basis of common sense and physics. At this point, should you have ‘missed the boat’ with regards to the above post, I have certainly have done so too.
Regards,
Over at icecap.us we can read that “Giant solar eruptions can cause the cosmic ray intensity on earth to dive suddenly over a few days. In the days following an eruption, cloud cover can fall by about 4 per cent. And the amount of liquid water in cloud droplets is reduced by almost 7 per cent”. ( http://icecap.us/index.php/go/joes-blog ) Add the negative net effect of cloud coverage on local temperature, and it seems that any discussion of CO2 is trivial by comparison.
The Dressler paper is more non-science babble.
Dressler: “I know that climate change does not cause any specific weather event. But I also know that humans have warmed the climate over the past century, and that this warming has almost certainly made the heat wave and drought more extreme than it would otherwise have been.” He was referring to the recent heat in Texas.
Climate experts have not yet demonstrated their form of science can ably predict the weather let alone any climate change. Yet, we sea engineers, mathematicians, and physicist parking satellites on asteroids. It is a simple matter of trust.
Being a student is great: I just remembered that I can download paywalled papers from a university computer. So I now have a copy of the paper, and I’ll be sure to give it a read later.
I’ve been trying to follow this with my lay-person’s understanding of the climate. I read the full paper and even though I don’t really understand it, something just doesn’t seem right.
Dessler says that clouds don’t change the climate. Yet clouds reflect the sun. So to my understanding if the cloud amount changes, so to will solar radiation that heats the surface. If cloud amounts increase, then less solar gets in resulting in less surface heating, and if cloud amounts decrease, then more solar gets in resulting in more surface heating. This sounds right to me.
Yet Dessler says that in the long term, increased cloud amounts will result in warming? This just doesn’t add up????
Also, if clouds reflect more solar than heat they trap, doesn’t that mean they cause a net negative feedback? And vice-versa if they reflect less solar than heat they trap, they become a positive feedback? Trying to put this together logically, Dessler just doesn’t seem to add up to me. Though I could be completely wrong, so hopefully someone can explain.
Would it be completely invalid to do the scatter plots with a logarithmic scale on the Y axis? Might make them easier to read in regard to outlier data points. As Willis has been trying to suggest recently, the climate system might actually be self-regulating, so a log scale might be more appropriate anyway.
Seems to me we’ve gone from a single run-away AGW train, to a bona-fide Warmist vs. Cloudist soap-box derby — with significant Cloudist handicaps, of course.
Pass the popcorn.
Bill Illis says @ur momisugly September 7, 2011 at 7:01 am
“The Dessler 2010 data is only comparable at a Reanalysis model level (ERA) versus just the cloud values from CERES.”
Perhaps the reanalysis procedure contains a hidden bias towards agreeing with the models? Are GCMs used in the reanalysis?
davidmhoffer says:
September 6, 2011 at 11:47 pm
“cloud cover in the dead of winter has a pronounced warming effect, and .. cloud cover at the height of summer has a pronounced cooling effect. It isn’t a matter of total cloud cover alone, it is also a matter of distribution over the seasons” …
… to say nothing about the distribution between day and night.
Which reminds me, the GCMs do distinguish between day and night effects; don’t they?
What is the significance of Dessler’s use of “pre-industrial control runs of 13 fully coupled climate models” versus SB11’s use of “de-trended 20th century runs”?
Wouldn’t the runs have to cover the same time period as the observed TOA fluxes? What does he mean by “pre-industrial”?
So many still getting Dessler’s name wrong.
highflight56433 says:
September 7, 2011 at 9:41 am
Over at icecap.us we can read that “Giant solar eruptions can cause the cosmic ray intensity on earth to dive suddenly over a few days. In the days following an eruption, cloud cover can fall by about 4 per cent. […] The Dressler paper is more non-science babble.
Yes, there in ‘non-science babble’ on both sides of the argument.
Leif Svalgaard says:
September 7, 2011 at 11:33 am
The Dressler paper is more non-science babble.
Yes, there in ‘non-science babble’ on both sides of the argument.
I see it as turf protecting…competing for attention. 🙂
…and who we trust.
Roy Spencer has posted an initial response to the Dessler paper on his blog
http://www.drroyspencer.com/2011/09/the-good-the-bad-and-the-ugly-my-initial-comments-on-the-new-dessler-2011-study/#comments
“About Research at Texas A&M University:”
“As one of the world’s leading research institutions, Texas A&M is in the vanguard in making significant contributions to the storehouse of knowledge, including that of science and technology. Research conducted at Texas A&M represents an annual investment of more than $630 million, which ranks third nationally for universities without a medical school, and underwrites approximately 3,500 sponsored projects. That research creates new knowledge that provides basic, fundamental and applied contributions resulting in many cases in economic benefits to the state, nation and world.”
hmmm….. follow the money. couldn’t help commenting, it just stood out to me.
“Giant solar eruptions can cause the cosmic ray intensity on earth to dive suddenly over a few days. In the days following an eruption, cloud cover can fall by about 4 per cent. And the amount of liquid water in cloud droplets is reduced by almost 7 per cent”.
Or maybe …
“The late 20th century warming correlates with very low overall GCR and with increased solar wind bursts that remove cloud forming ions via the mechanism electroscavenging. There is an observed reduction in planetary cloud cover during the warming period.”
Sounds like two separate mechanisms. Leif may not like the first, but what about the second?
I bring this up because we did have a couple of big flares earlier this summer (or late spring) and this summer has been warmer than most skeptics expected following a Lan Niña. Are these related?
@ur momisugly#
#
George E. Smith says:
September 6, 2011 at 10:02 pm
“What if the average cloud cover should drop to 60% for the next 30, 60, 90 years or so; will the earth get warmer or cooler as a result ??”
From this:
http://1.2.3.9/bmi/www.climate4you.com/images/CloudCoverAllLevel%20AndWaterColumnSince1983.gif
it looks like low level cloud is less when it is warmer, and you can see the increased low level cloud during the mid 1980`s and the early 1990`s temperature drops. Note how the mid level clouds change in the opposite direction to low level clouds seasonally, and tend to as a trend too.
Richard M says:
September 7, 2011 at 12:50 pm
Sounds like two separate mechanisms. Leif may not like the first, but what about the second?
Same answer as to tallbloke:
tallbloke says:
September 7, 2011 at 7:21 am
The fact is the sun in the past 50 years has been more active than anytime in past 400 years.
Fact: “Recent 10Be values are low; however, they do not indicate unusually high recent solar activity compared to the last 600 years.”
http://www.leif.org/EOS/2009GL038004-Berggren.pdf
Thanks. That makes sense. I had not allowed for the effect of the passage of time with hightened cloud cover. What a great site this is. Socratic dialogue on an epic scale. I learn new stuff all the time here.