Dr. Roy Spencer went to Washington to give testimony today to the Senate Environment and Public Works Committee. Here is his presentation. While not as technical as Lord Moncktons paper at APS (since it had to be simplified for a congressional hearing), it nonetheless says the same thing – climate sensitivity is overstated by models and not supported by observational data. – Anthony
Update: See the complete testimony on YouTube here: http://www.youtube.com/watch?v=Qzf6z-oHP8U
Testimony of Roy W. Spencer before the
Senate Environment and Public Works Committee on 22 July 2008
A printable PDF of this testimony can be found here
I would like to thank Senator Boxer and members of the Committee for allowing me to discuss my experiences as a NASA employee engaged in global warming research, as well as to provide my current views on the state of the science of global warming and climate change.
I have a PhD in Meteorology from the University of Wisconsin-Madison, and have been involved in global warming research for close to twenty years. I have numerous peer reviewed scientific articles dealing with the measurement and interpretation of climate variability and climate change. I am also the U.S. Science Team Leader for the AMSR-E instrument flying on NASA’s Aqua satellite.
1. White House Involvement in the Reporting of Agency Employees’ Work
On the subject of the Administration’s involvement in policy-relevant scientific work performed by government employees in the EPA, NASA, and other agencies, I can provide some perspective based upon my previous experiences as a NASA employee. For example, during the Clinton-Gore Administration I was told what I could and could not say during congressional testimony. Since it was well known that I am skeptical of the view that mankind’s greenhouse gas emissions are mostly responsible for global warming, I assumed that this advice was to help protect Vice President Gore’s agenda on the subject.
This did not particularly bother me, though, since I knew that as an employee of an Executive Branch agency my ultimate boss resided in the White House. To the extent that my work had policy relevance, it seemed entirely appropriate to me that the privilege of working for NASA included a responsibility to abide by direction given by my superiors.
But I eventually tired of the restrictions I had to abide by as a government employee, and in the fall of 2001 I resigned from NASA and accepted my current position as a Principal Research Scientist at the University of Alabama in Huntsville. Despite my resignation from NASA, I continue to serve as Team Leader on the AMSR-E instrument flying on the NASA Aqua satellite, and maintain a good working relationship with other government researchers.
2. Global Warming Science: The Latest Research
Regarding the currently popular theory that mankind is responsible for global warming, I am very pleased to deliver good news from the front lines of climate change research. Our latest research results, which I am about to describe, could have an enormous impact on policy decisions regarding greenhouse gas emissions.
Despite decades of persistent uncertainty over how sensitive the climate system is to increasing concentrations of carbon dioxide from the burning of fossil fuels, we now have new satellite evidence which strongly suggests that the climate system is much less sensitive than is claimed by the U.N.’s Intergovernmental Panel on Climate Change (IPCC).
Another way of saying this is that the real climate system appears to be dominated by “negative feedbacks” — instead of the “positive feedbacks” which are displayed by all twenty computerized climate models utilized by the IPCC. (Feedback parameters larger than 3.3 Watts per square meter per degree Kelvin (Wm-2K-1) indicate negative feedback, while feedback parameters smaller than 3.3 indicate positive feedback.)
If true, an insensitive climate system would mean that we have little to worry about in the way of manmade global warming and associated climate change. And, as we will see, it would also mean that the warming we have experienced in the last 100 years is mostly natural. Of course, if climate change is mostly natural then it is largely out of our control, and is likely to end — if it has not ended already, since satellite-measured global temperatures have not warmed for at least seven years now.
2.1 Theoretical evidence that climate sensitivity has been overestimated
The support for my claim of low climate sensitivity (net negative feedback) for our climate system is two-fold. First, we have a new research article1 in-press in the Journal of Climate which uses a simple climate model to show that previous estimates of the sensitivity of the climate system from satellite data were biased toward the high side by the neglect of natural cloud variability. It turns out that the failure to account for natural, chaotic cloud variability generated internal to the climate system will always lead to the illusion of a climate system which appears more sensitive than it really is.
Significantly, prior to its acceptance for publication, this paper was reviewed by two leading IPCC climate model experts – Piers Forster and Isaac Held– both of whom agreed that we have raised a legitimate issue. Piers Forster, an IPCC report lead author and a leading expert on the estimation of climate sensitivity, even admitted in his review of our paper that other climate modelers need to be made aware of this important issue.
To be fair, in a follow-up communication Piers Forster stated to me his belief that the net effect of the new understanding on climate sensitivity estimates would likely be small. But as we shall see, the latest evidence now suggests otherwise.
2.2 Observational evidence that climate sensitivity has been overestimated
The second line of evidence in support of an insensitive climate system comes from the satellite data themselves. While our work in-press established the existence of an observational bias in estimates of climate sensitivity, it did not address just how large that bias might be.
But in the last several weeks, we have stumbled upon clear and convincing observational evidence of particularly strong negative feedback (low climate sensitivity) from our latest and best satellite instruments. That evidence includes our development of two new methods for extracting the feedback signal from either observational or climate model data, a goal which has been called the “holy grail” of climate research.
The first method separates the true signature of feedback, wherein radiative flux variations are highly correlated to the temperature changes which cause them, from internally-generated radiative forcings, which are uncorrelated to the temperature variations which result from them. It is the latter signal which has been ignored in all previous studies, the neglect of which biases feedback diagnoses in the direction of positive feedback (high climate sensitivity).
Based upon global oceanic climate variations measured by a variety of NASA and NOAA satellites during the period 2000 through 2005 we have found a signature of climate sensitivity so low that it would reduce future global warming projections to below 1 deg. C by the year 2100. As can be seen in Fig. 1, that estimate from satellite data is much less sensitive (a larger diagnosed feedback) than even the least sensitive of the 20 climate models which the IPCC summarizes in its report. It is also consistent with our previously published analysis of feedbacks associated with tropical intraseasonal oscillations3.
Fig. 1. Frequency distributions of feedback parameters (regression slopes) computed from three-month low-pass filtered time series of temperature (from channel 5 of the AMSU instrument flying on the NOAA-15 satellite) and top-of-atmosphere radiative flux variations for 6 years of global oceanic satellite data measured by the CERES instrument flying on NASA’s Terra satellite; and from a 60 year integration of the NCAR-CCSM3.0 climate model forced by 1% per year CO2 increase. Peaks in the frequency distributions indicate the dominant feedback operating. This NCAR model is the least sensitive (greatest feedback parameter value) of all 20 IPCC models.
A second method for extracting the true feedback signal takes advantage of the fact that during natural climate variability, there are varying levels of internally-generated radiative forcings (which are uncorrelated to temperature), versus non-radiative forcings (which are highly correlated to temperature). If the feedbacks estimated for different periods of time involve different levels of correlation, then the “true” feedback can be estimated by extrapolating those results to 100% correlation. This can be seen in Fig. 2, which shows that even previously published4 estimates of positive feedback are, in reality, supportive of negative feedback (feedback parameters greater than 3.3 Wm-2K-1).
Fig. 2. Re-analysis of the satellite-based feedback parameter estimates of Forster and Gregory (2006) showing that they are consistent with negative feedback rather than positive feedback (low climate sensitivity rather than high climate sensitivity).
2.3 Why do climate models produce so much global warming?
The results just presented beg the following question: If the satellite data indicate an insensitive climate system, why do the climate models suggest just the opposite? I believe the answer is due to a misinterpretation of cloud behavior by climate modelers.
The cloud behaviors programmed into climate models (cloud “parameterizations”) are based upon researchers’ interpretation of cause and effect in the real climate system5. When cloud variations in the real climate system have been measured, it has been assumed that the cloud changes were the result of certain processes, which are ultimately tied to surface temperature changes. But since other, chaotic, internally generated mechanisms can also be the cause of cloud changes, the neglect of those processes leads to cloud parameterizations which are inherently biased toward high climate sensitivity.
The reason why the bias occurs only in the direction of high climate sensitivity is this: While surface warming could conceivably cause cloud changes which lead to either positive or negative cloud feedback, causation in the opposite direction (cloud changes causing surface warming) can only work in one direction, which then “looks like” positive feedback. For example, decreasing low cloud cover can only produce warming, not cooling, and when that process is observed in the real climate system and assumed to be a feedback, it will always suggest a positive feedback.
2.4 So, what has caused global warming over the last century?
One necessary result of low climate sensitivity is that the radiative forcing from greenhouse gas emissions in the last century is not nearly enough to explain the upward trend of 0.7 deg. C in the last 100 years. This raises the question of whether there are natural processes at work which have caused most of that warming.
On this issue, it can be shown with a simple climate model that small cloud fluctuations assumed to occur with two modes of natural climate variability — the El Nino/La Nina phenomenon (Southern Oscillation), and the Pacific Decadal Oscillation — can explain 70% of the warming trend since 1900, as well as the nature of that trend: warming until the 1940s, no warming until the 1970s, and resumed warming since then. These results are shown in Fig. 3.
Fig. 3. A simple climate model forced with cloud cover variations assumed to be proportional to a linear combination of the Southern Oscillation Index (SOI) and Pacific Decadal Oscillation (PDO) index. The heat flux anomalies in (a), which then result in the modeled temperature response in (b), are assumed to be distributed over the top 27% of the global ocean (1,000 meters), and weak negative feedback has been assumed (4 W m-2 K-1).
While this is not necessarily being presented as the only explanation for most of the warming in the last century, it does illustrate that there are potential explanations for recent warming other that just manmade greenhouse gas emissions. Significantly, this is an issue on which the IPCC has remained almost entirely silent. There has been virtually no published work on the possible role of internal climate variations in the warming of the last century.
3. Policy Implications
Obviously, what I am claiming today is of great importance to the global warming debate and related policy decisions, and it will surely be controversial. These results are not totally unprecedented, though, as other recently published research6 has also led to the conclusion that the real climate system does not exhibit net positive feedback.
While it will take some time for the research community to digest this new information, it must be mentioned that new research contradicting the latest IPCC report is entirely consistent with the normal course of scientific progress. I predict that in the coming years, there will be a growing realization among the global warming research community that most of the climate change we have observed is natural, and that mankind’s role is relatively minor.
While other researchers need to further explore and validate my claims, I am heartened by the fact that my recent presentation of these results to an audience of approximately 40 weather and climate researchers at the University of Colorado in Boulder last week (on July 17, 2008 ) led to no substantial objections to either the data I presented, nor to my interpretation of those data.
And, curiously, despite its importance to climate modeling activities, no one from Dr. Kevin Trenberth’s facility, the National Center for Atmospheric Research (NCAR), bothered to drive four miles down the road to attend my seminar, even though it was advertised at NCAR.
I hope that the Committee realizes that, if true, these new results mean that humanity will be largely spared the negative consequences of human-induced climate change. This would be good news that should be celebrated — not attacked and maligned.
And given that virtually no research into possible natural explanations for global warming has been performed, it is time for scientific objectivity and integrity to be restored to the field of global warming research. This Committee could, at a minimum, make a statement that encourages that goal.
REFERENCES
1. Spencer, R.W., and W.D. Braswell, 2008: Potential biases in cloud feedback diagnosis:
A simple model demonstration. J. Climate, in press.
2. Allen, M.R., and D.J. Frame, 2007: Call off the quest. Science, 318, 582.
3. Spencer, R.W., W. D. Braswell, J. R. Christy, and J. Hnilo, 2007: Cloud and radiation
budget changes associated with tropical intraseasonal oscillations. Geophys. Res.
Lett., 34, L15707, doi:10.1029/2007GL029698.
4. Forster, P. M., and J. M. Gregory, 2006: The climate sensitivity and its components
diagnosed from Earth Radiation Budget data. J. Climate, 19, 39-52.
5. Stephens, G. L., 2005: Clouds feedbacks in the climate system: A critical review. J.
Climate, 18, 237-273.
6. Schwartz, S. E., 2007: Heat capacity, time constant, and sensitivity of the Earth’s
climate system. J. Geophys. Res., 112, D24S05, doi:10.1029/2007JD008746.
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Jeez,
Trouble is that some likely think that death and misery are a necessary evil, to prevent more further down the road, even to human extinction. I don’t believe this far off the mark with the public that has bought into these dire predictions from the scientific community, UN, federal governments, and movies, be it hothouse or iceage.
If it were so, so be it. But as you say, let’s base our actions on good science and good planning. But from what I’ve seen, it’s all a sham, and way out of hand, and we may really have reached a tipping point of no return. I don’t see how this unscientific and irresponsible behavior is going to stop now or later.
“Nature will be the final arbiter, but it would be nice if we didn’t do stupid things out of misplaced ignorance that leads to death and misery before that happens.” jeez
Perhaps “Nature” is waiting to see who else will climb out on that tree limb called “AGW” or to give others time to reconsider before the “cold” facts of reality cause that limb to break off.
jeez (20:50:27) : “….have witnessed the history over the last 10 or 20 years and yes you are being naive”.
May be, but not necessarily. It took Presidents Reagan and Gorbachev, with more trust and respect between each other, to end the cold war. Supreme Court justices Antonin Scalia and Ruth Bader Ginsburg are great friends, which takes away lots of the cynical interpretations about their opinions, even though ideologically they are poles apart. William F. Buckley, Jr. and long time ACLU Director Ira Glasser were great friends, which brought a sense of sincerity and openness to their discussions. I can go on….
Someone must work hard to remove the adversarial relationship between AGW supporters and critics, and if they can establish a level of trust between each other through this effort, it can bring a fresh more beneficial atmosphere for an open discussion.
“Someone must work hard to remove the adversarial relationship between AGW supporters and critics, and if they can establish a level of trust between each other through this effort, it can bring a fresh more beneficial atmosphere for an open discussion.” John McLondon
I must agree though I have (to my shame) anticipated with glee the revenge of watching others eat crow. But our real enemies are not flesh and blood as the Good Book says.
statePoet1775 (09:11:55) : “But our real enemies are not flesh and blood as the Good Book says.”
Absolutely.
John McLondon,
What is adversarial about insisting that journals and organizations enforce disclosure standards they already have in place?
What is adversarial about pointing out a lack of disclosure currently occurring?
Jeez,
I am all for complete disclosure. But let us look the situation from the other side. Occasional demands on raw data seem fine. But the context in which such requests are made is important. Systematic requests, particularly targeting at IPCC editors, appear suspicious. Most often complete raw data is requested only when there is a suspicion of fraud, or other consistency problems. These requests are generally made by other scientists actively working in the area, not by outsiders with a pre-established and well publicized view on the topic whose main objective, as it appears to any reasonable person, is nothing but to look for mistakes so that they could make a disproportional case out of the smallest mistakes.
Many journals do not have a clear raw data disclosure policy, although if there are suspicions of fraud they all will require raw data. Even for Royal Society journals, the requirement is not without boundaries (“As a condition of acceptance authors agree to honour any reasonable request by other researchers for materials, methods, or data necessary to verify the conclusion of the article.” Any REASONBLE request by other RESEARCHERS).
But requesting data is not the main problem. In my opinion, some of the articles here and in other blogs appear to criticize scientists based on trivial reasons, and it is with this background such raw data requests are made: (1) Hansen refusing to accept the debate organized by a unofficial student organization, (2) now we have the two quotes from the IPCC Chair, who was actually installed there by President Bush because he wanted to remove the previous IPCC Chair Watson, to make him look stupid with a picture to portray him as a caveman (it was changed now to invoke another repulsive feeling among the followers – association with Gore) (3) Monckton’s intense claim that an unreviewed publication was indeed peer-reviewed and APS should somehow acknowledge that “at once”, (4) McIntyre’s comments like “Hansen bulldog Gavin Schmidt” and his private time “flexibly includes 9 to 5” “has provided bulldog services on behalf of his boss”, in his blog, etc. creates a perception of unreasonableness and personality interest from the side of AGW critics. When we look at such rhetoric from AGW critics, it is clear the relationship is adversarial. I am unhappy about this, because it is undermining the credibility of blogs critical of AGW. It also gives the perception that these inquiries are not about scientific integrity or curiosity, rather they are a means to further the preconceived beliefs held by those who are requesting those data.
Now, I have not gone to the AGW believers’ side to see what tactics they use, I assume the AGW endorsers’ blogs by non-scientists may contain such problems. But whatever the AGW people are saying, it is not going to change what we see with the critics’ side. The thing that distresses me the most is the determination of AGW critics to keep it that way. I wish the situation was different.
No, no, and no, you are conflating political debate and other issues with the one issue I am concerned about, disclosure. Either scientists disclose or they are not scientists. Your nitpicking about whether requests are suspicious or not is not relevant. Much of the rest of your comment is not relevant.
Many journals do have disclosure policies. These are not enforced against the players. The IPCC has archiving and disclosure policies. These are not enforced against the players. Any insults they incur as a result of not behaving as scientists they have brought upon themselves. This needs to stop. Transparency is the only path to resolution.
Scientist do not have to “trust” to behave like scientists. If they don’t disclose they are not scientists. Period. End of story. That’s all she wrote. The fat lady has sung.
Jeez,
“Scientist do not have to “trust” to behave like scientists. If they don’t disclose they are not scientists. Period. End of story. That’s all she wrote. The fat lady has sung.”
No no, don’t make her sing too fast!
I was talking about the general environment (in which case my previous post is fully valid), but I understand your position is a narrower one regarding raw data disclosure alone. For one thing, we cannot take the narrower view without putting it within the general context. But for argument sake let us move on.
I was looking at few journals, for example “Climate”, “geophysical research letters” etc. and I cannot find a raw data disclosure policy. I am not even aware of such policies in journals I deal with in my field. All data must be provided with patents for someone to duplicate the invention. But for scientific papers I am not aware of a requirement that all data must be provided, without probable cause for further investigation. Apart from the Royal Society Journals (where there is a clear policy for reasonable requests), I really cannot find such policy statements where I looked. You think I am not looking at the right place?
I don’t have time to find multiple examples, but here’s one.
http://www.sciencemag.org/about/authors/prep/gen_info.dtl#datadep
Ok and another.
http://publishing.royalsociety.org/index.cfm?page=1595#question6
Jeez,
Yes, thanks. The requirement by Science does not seem to be an absolute one. Many others do not even have a policy. The most detailed policy is, as you pointed out, by the Royal Society publications. We will see what happens with McIntyre’s request, whether they will consider that as a reasonable request.
More than ever I am so convinced that each side has taken a hard line position, and wants to keep it that way to the end. I am so glad I am not in climate science, if I were, after seeing all these intense scrutiny on scientific and personal matters, I would have changed my field quickly. It is not worth the trouble. It is disappointing to see comments by Hansen about trials, but it is more disappointing to see how critics are making trivialities (not the raw data requests, but other things I posted earlier) as issues to discredit AGW. In my view it affects the credibility. I hope it will change and only real issues will be used for discussions and debate. We will see.
your blog is getting better )
I haven’t been able to review all the comments but at almost the very end
of the hearing with Dr. Spencer and Dr. Trenberth (and others), the Democrat male Senator from Rhode Island gave Dr. Trenberth an opportunity to attack
Dr. Spencer’s research and Dr. Trenberth did so citing some specifics he
maintained Dr. Spencer got wrong. Dr. Spencer, of course, didn’t get a chance to rebut Trenberth’s assertions. Does anybody know if Dr. Spencer has responded in writing to Trenberth’s claims and, if so on the web, where?
Thanks.
By the way, the blogger “tamino” has done a nice job explaining what how he thinks Spencer is fooling himself here: http://tamino.wordpress.com/2008/08/01/spencers-folly-3/
Tamino’s criticisms make the most sense if you look at Spencer’s full presentation given at Colorado State University: http://climatesci.org/wp-content/uploads/spencer-ppt.pdf rather than just the abbreviated version presented in this post.
Chris Monckton’s no mathematician, at least not according to Wiki:
”
In 1974 at the age of 22, Monckton joined the Yorkshire Post, where he worked as a reporter and leader-writer. From 1977 to 1978, he worked at Conservative Central Office as a press officer, becoming the editor of the Roman Catholic newspaper The Universe in 1979, then managing editor of The Sunday Telegraph Magazine in 1981. He joined the English tabloid newspaper, Evening Standard, as a leader-writer in 1982.[1]
[edit] Politics
Monckton was born on 14 February 1952, the eldest son of the 2nd Viscount Monckton of Brenchley. He was educated at Harrow School, Churchill College, Cambridge where he read classics and University College, Cardiff, where he obtained a diploma in journalism.[1]
…
He returned to Conservative Central Office in late 1982, this time as a policy advisor for Margaret Thatcher.[2] In 1986, he became assistant editor of the newly established, and now defunct, newspaper Today. He was a consulting editor for the Evening Standard from 1987 to 1992 and was its chief leader-writer from 1990 to 1992.[1]
Monckton was an unsuccessful candidate for a Conservative seat in the House of Lords in a March 2007 by-election caused by the death of Lord Mowbray and Stourton. He had been highly critical of the way that the Lords has been reformed, describing the by-election procedure, with 43 candidates and 47 electors, as “a bizarre constitutional abortion.”[3]”
[…] I have yet to see any skeptic scientist, let alon Mr. Crichton, do this. In no particular order: Roy Spencer’s testimony before congress backs up Monckton’s assertions on climate sensit… Roy W. Spencer: Global Warming and Nature’s Thermostat CO2 Science Still Waiting For Greenhouse […]
Oh my. This is my first reading of this blog and like most, there are some folks that truly understand the subject and many that simply offer emotionally driven opinions. I found the exchange between jeez and John McLondon to be at once satisfying and disturbing. It was satisfying in that Jeez focused on the crux of the matter (the need for full data disclosure by The Team) and refused to be diverted. Disturbing because even while pinned to the display mat like a butterfly specimen, John McLondon refused to open his eyes and see the fundamental issue. AGW and the attendant public policy debate are too important to excuse any lack of transparency. Regardless of which camp carries the argument, literally billions of human beings’ lives and livelihoods are at stake here. Please go and read the nonsense described in:
http://www.climateaudit.org/?p=3352
Forget prosecuting oil company executives as Mr. Hansen has so dysfunctionally advocated. Go after the scientists that are withholding the data we so desperately need to make the critical scientific and public policy decisions that will determine who prospers and who doesn’t and obviously more importantly, who lives and who dies. This isn’t some antiseptic game played out by nerds in lab coats and policy wonks. Millions of people’s lives hang in the balance on both sides of the equation. Not having openly available data to simply follow where it takes us is unconscionable.
Reply: Mr Aardvark received no compensation for the above post~charles the moderator aka jeez