From the BNL press release, some serious questions about climate sensitivity and aerosols.
Why Hasn’t Earth Warmed as Much as Expected?
New report on climate change explores the reasons
January 19, 2010 UPTON, NY – Planet Earth has warmed much less than expected during the industrial era based on current best estimates of Earth’s “climate sensitivity”—the amount of global temperature increase expected in response to a given rise in atmospheric concentrations of carbon dioxide (CO2). In a study to be published in the Journal of Climate, a publication of the American Meteorological Society (the early online release of the paper is available starting 19 January 2010; the link is given below), Stephen Schwartz, of Brookhaven National Laboratory, and colleagues examine the reasons for this discrepancy.
According to current best estimates of climate sensitivity, the amount of CO2 and other heat-trapping gases added to Earth’s atmosphere since humanity began burning fossil fuels on a significant scale during the industrial period would be expected to result in a mean global temperature rise of 3.8°F—well more than the 1.4°F increase that has been observed for this time span. Schwartz’s analysis attributes the reasons for this discrepancy to a possible mix of two major factors: 1) Earth’s climate may be less sensitive to rising greenhouse gases than currently assumed and/or 2) reflection of sunlight by haze particles in the atmosphere may be offsetting some of the expected warming.
“Because of present uncertainties in climate sensitivity and the enhanced reflectivity of haze particles,” said Schwartz, “it is impossible to accurately assign weights to the relative contributions of these two factors. This has major implications for understanding of Earth’s climate and how the world will meet its future energy needs.”
A third possible reason for the lower-than-expected increase of Earth’s temperature over the industrial period is the slow response of temperature to the warming influence of heat-trapping gases. “This is much like the lag time you experience when heating a pot of water on a stove,” said Schwartz. Based on calculations using measurements of the increase in ocean heat content over the past fifty years, however, this present study found the role of so-called thermal lag to be minor.
A key question facing policymakers is how much additional CO2 and other heat-trapping gases can be introduced into the atmosphere, beyond what is already present, without committing the planet to a dangerous level of human interference with the climate system. Many scientists and policymakers consider the threshold for such dangerous interference to be an increase in global temperature of 3.6°F above the preindustrial level, although no single threshold would encompass all effects.
The paper describes three scenarios: If Earth’s climate sensitivity is at the low end of current estimates as given by the Intergovernmental Panel on Climate Change, then the total maximum future emissions of heat-trapping gases so as not to exceed the 3.6° threshold would correspond to about 35 years of present annual emissions of CO2 from fossil-fuel combustion. A climate sensitivity at the present best estimate would mean that no more heat-trapping gases can be added to the atmosphere without committing the planet to exceeding the threshold. And if the sensitivity is at the high end of current estimates, present atmospheric concentrations of heat-trapping gases are such that the planet is already committed to warming that substantially exceeds the 3.6° threshold.
The authors emphasize the need to quantify the influences of haze particles to narrow the uncertainty in Earth’s climate sensitivity. This is much more difficult than quantifying the influences of the heat-trapping gases. Coauthor Robert Charlson of the University of Washington likens the focus on the heat trapping gases to “looking for the lost key under the lamppost.”
Schwartz observes that formulating energy policy with the present uncertainty in climate sensitivity is like navigating a large ship in perilous waters without charts. “We know we have to change the course of this ship, and we know the direction of the change, but we don’t know how much we need to change the course or how soon we have to do it.”
Schwartz and Charlson coauthored the paper with Ralph Kahn, NASA Goddard Space Flight Center in Maryland; John Ogren, NOAA Earth System Research Laboratory in Colorado; and Henning Rodhe, Stockholm University.
The early online release of the paper is available at AMS’s journals online site.
Founded in 1919, the AMS has a membership of more than 14,000 professionals, professors, students, and weather enthusiasts. AMS publishes nine atmospheric and related oceanic and hydrologic journals, sponsors multiple conferences annually, and directs numerous education and outreach programs and services. For more information see www.ametsoc.org.
Research at Brookhaven was funded by the U.S. Department of Energy Office of Science.
h/t to WUWT commenter “Don S”
Richard M: cherry picking? No way… The plot is a comparison between IPCC “wrong” predictions from 2000 and other theories.
Here are the figures for yearly UAH anomalies since 2000
0.04, 0.2, 0.31, 0.28, 0.19, 0.34, 0.26, 0.28, 0.05, 0.26
which makes deviations from 2000 look like
0, 0.16, 0.27, 0.24, 0.15, 0.3, 0.22, 0.24, 0.01, 0.22
it looks like, except for 2008, all these data fall well within the IPCC range. You should for example try plotting these values along with a straight line with a 0.03 slope (the IPCC estimate) and one with a 0.01 slope (the Schwartz estimate). It’s quite telling.
KSW, you appear to have selective reading. He also stated the climate sensitivity may be assumed to be too high. So now you have Latif stating that ocean oscillations may cause a couple of decades of cooling, you have Schwartz stating that the climate sensitivity may be lower then thought, and you have the NOAA saying that 15 years of no warming would invalidate the models at the 95% while we have 11 such years already past. There is a time to begin to re-evaluate your position. I don’t see why you should have to be the last in line to do so when others are already leading the way.
“current best estimates of climate sensitivity,”
It is getting really infuriating now.
What, exactly, were the $billions spent on? Why are these people still getting funding for showing that which we can all agree upon already? It warmed up a bit. Was CO2 the cause? Come on guys.
KSW – Please,please,please^100 show us – “within 30 seconds of research with credible sources.” I will even, for the course of this thought experiment, not argue the provenance, or credibility of said sources. Show us some real world, repeatable, falsifiable evidence that what you claim is possible. Please. I want to believe.
I can’t stand it any longer. Here are the facts as I know them:
1) 95% of the GHG warming comes from water vapor
2) CO2 comprises 5% of GHG warming
3) Natural sources of CO2 (volcanoes, etc.) contribute 4.75% of the 5%
4) Anthropogenic CO2 contribution = 0.25%
The Null Hypothesis would frame the scientific question as: “The anthropogenic contribution of 0.25% of total GHG to planetary warming has no measurable effect”.
I believe the data collected to date (Vostock ice cores, paleoclimatology assessments, tree ring data, and 20th century temperature measurements, ice sheet coverage, etc.) has resoundingly proved the Null hypothesis. I’m no climate scientist, but why is this so hard to see?
The answer is simple and obvious.
ALIENS ARE STEALING OUR HEAT!!!!!!!!!!!!
A lost key under a lamppost? I think that I might manage to find that. It might be more analogous if we were to add that our knowledge is so limited that we do not know in which street, in which city, on what continent the lamppost is, and that it might have been on, say, Krakatoa, before it blew itself up. Seems to me that you scientific types have a way to go yet.
Is the graphic by Spencer part of the article or just something posted as part of this blog post?
Is the article or a preprint version of it available somewhere other than behind the AMS paywall?
A lot of the comments above are about the graphic, which may or may not be part of the actual article.
>>Ken Harvey
The analogy may make more sense if you have the full story.
It’s dark. A drunk is wandering around under a lamp post looking for something. A helpful stranger walks by and asks what the guy’s looking for. “My key”, says the drunk. Thinking he’ll get the drunk off the street, the stranger starts to help look. After 15 minutes and no success, the stranger asks the drunk what he was doing when he lost the key. “I was walking through that alley”, says the drunk. After a pause, the stranger asks, “why are we looking for the key under the lamp post”. The drunk replies, “because the light’s better”.
So, when you’re looking for a key under a lamp post, you’re searching for something in an area that’s easy for looking, but unlikely to prove successful.
KSW is “old school” AGW:
We know the conclusion
The data doesn’t fit the conclusion
Because there’s a consensus on the conclusion, the data must be wrong
We must find a reason to adjust the data
It’s worse than we thought
…. and by the way KSW, no one is denying you your thought process, but a lot are skeptical of it, including Schwartz, perhaps.
KSW (06:47:58) :
I couldn’t read all the comments but most of you have displayed such an obvious lack of knowledge on AGW that can be dispelled within 30 seconds of research with credible sources.
For your information; Stephen Shwartz is no AGW denier. This paper is telling you that physically the amount of warming that has occurred is less than the physics of greenhouse gases should lead to. This is not in any real dispute and doesn’t come as any surprise to anyone that has researched AGW to any level of competence.
If you’re going to disparage the intelligence of WUWT readers, and inform us, at the very least it behooves you to at least state your thesis with a modicum of competence. This paper is not about the “physics” of CO2 induced greenhouse warming. It regards the amplification of the effect of increased CO2 concentration by something referenced in the article as uncertainties in climate sensitivity. These are unknown “physics” factors and are based on non-observational data, ie., assumptions. The authors agree that IPCC estimates may be incorrect. If, with your uncalculable intellectual capacity you know the sensivity, please show us your mathematical formula, or point us to others who have determined the appropriate value, which fits the observational data.
Constructing asymmetry:
Take 20 models, each a straight line from the origin to a point in the year 2100.
Choose as endpoints: 6.5 & 4times6 & 5times3 & 9times1.5 & 1
Declare the mean=3 as best estimate
90% of the models are between 1.5 and 6
Com´ on, Folks!
Steven schwartz is in this research deliberately utterly Political Correct..!
Does nobody know or remember anymore about his research that corroborated the theory of Ferenc Miskolczi about the limited possibility of the atmosphere to heat up?
Just see http://www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf
Give him a break
“Rob Vermeulen (07:33:22) :
Here are the figures for yearly UAH anomalies since 2000
0.04, 0.2, 0.31, 0.28, 0.19, 0.34, 0.26, 0.28, 0.05, 0.26
which makes deviations from 2000 look like
0, 0.16, 0.27, 0.24, 0.15, 0.3, 0.22, 0.24, 0.01, 0.22
it looks like, except for 2008, all these data fall well within the IPCC range. You should for example try plotting these values along with a straight line with a 0.03 slope (the IPCC estimate) and one with a 0.01 slope (the Schwartz estimate). It’s quite telling.”
The linear trend for UAH anomalies is 0.0053*x + 0.1973. That is 0.53°C warmer in 100 years.
The lowest IPCC model warms 1.5°C in 100 years.
Try subtracting 0.197°C instead of 0.04°C
Has the Earth warmed any further than it would have warmed following the natural cycles that took us from the Little Ice Age?
If not, what the hell are we talking about?
Okay now it’s my turn to take a shot at this silly analogy:
“Schwartz observes that formulating energy policy with the present uncertainty in climate sensitivity is like navigating a large ship in perilous waters without charts. ‘We know we have to change the course of this ship, and we know the direction of the change, but we don’t know how much we need to change the course or how soon we have to do it.'”
If we are comparing energy policy to navigating a large ship in perilous waters then the problem has nothing to do with charts. The real problem is that we are attempting to influence the height, frequency, and severity of chaotic ocean waves by shutting off the ship’s engines.
The more I see the trashing of setled science, the more I like the climate hypothesis of Dr. Miskolczi.
Galen Haugh and Henry Galt – try this: http://scholar.google.ca/
steven (07:46:59) and philincalifornia – have you even bothered to look at Dr Schwartz’s home page to get some background on this paper?
Tim Clark – also for you check his home page, you will find it instructive. We are talking about estimates – that why there are error bars. The response of the climate to rising greenhouse gases is still within the error bars as presented by the IPCC. However the greatest uncertainty is due to uncertainty in the effect of aerosols – still doesn’t change anything about the role of CO2.
Alejandro (10:36:56) : asked “Has the Earth warmed any further than it would have warmed following the natural cycles that took us from the Little Ice Age?
If not, what the hell are we talking about?”
Yes it has.
I really wish this kind of report include a povenance on the data used. WHICH temperature data set was used to determin the warming measured?
If the models are toast when compared to data sets like GHCN and USHCN that have had massive deletions of cold thermometers or large “adjutesments” of questionable nature leading ot 3 F of “rise” in the data that is not in the “raw” data; then this report would be even more spectacular.
i’m glad to see it, but frankly, we’re getting colder right now, not warmer.
In Florida an introduced species is getting a taste of 1970’s style cold and “It’s Raining Iguanas in Florida”. In Australia they are having snow… in Summer. Perhaps not unheard of, but incompatible with the notion of “warming”. The folks of Peru are dying in the cold. We’ve had a cold induced failure of seed production. (also not unheard of, but not what would happen in ‘warming’ conditions). The UK is one big blanket of snow. Yeah, happened before (1800s, 1970s? ) but again, not what happens with “warming”.
There is a huge list of such things.
So we have a (very welcome!) report saying the models are busted. But it looks to me like they are “busted” even with comparision to an artificially warmed temperature series. So what are they when compared to “Picture Window Science”? Horridly wrong. Just horridly wrong.
FWIW: Just had a drenching downpour. California is getting hammered. Storms like I remember from back in the ’60s and ’70s. One weather report was calling for 4 to 5 feet ( 1.5 ish meters) of snow from this storm alone and for 3 inches of rain ( 7.5 cm ) in one dump over large areas of the State. In some years we don’t get that much all year. 7 inches annually is common in many areas. About 1956? 58? There was a series of monster storms dumped something like 18 feet of snow on the Donner Pass. This year feels kind of like that one to me…
Note to all Climate Scientists: Go To The Window. Open Eyes. Think.
“Why hasnt the earth warmed as much as we expected?” This question is logically on a level with:
Cottleston, Cottleston, Cottleston Pie,
Why does a chicken,
I don’t know why.
Ask me a riddle and I reply,Cottleston, Cottleston, Cottleston Pie…”
(Winnie the Poo)
KSW (11:40:18) :
We are talking about estimates – that why there are error bars. The response of the climate to rising greenhouse gases is still within the error bars as presented by the IPCC. However the greatest uncertainty is due to uncertainty in the effect of aerosols – still doesn’t change anything about the role of CO2.
I wonder whether you know what error bars are and how they are computed. In large complicated ensembles of programs they should be computed using the maximum likelihood method, i.e. a method that changes according to the errors all the input parameters and gives the errors on the output parameters.
This is not how the IPCC model estimates have been done, by the admission in the AR4 report, chapter, 8.1.2.2 Metrics of Model Reliability has the following amazing statement:
The above studies show promise that quantitative metrics for the likelihood of model projections
may be developed, but because the development of robust
metrics is still at an early stage, the model evaluations presented
in this chapter are based primarily on experience and physical
reasoning, as has been the norm in the past.
and in http://www.ipcc-nggip.iges.or.jp/public/gp/english/6_Uncertainty.pdf
the equally amazing:
Ideally, emissions estimates and uncertainty ranges would both be derived from source-specific measured data. Since it is not practical to measure every emission source in this way, estimates are often based on the known characteristics of typical sources taken to be representative of the population. This introduces additional uncertainties, because it must be assumed that the population of these sources behave, on average, like the sources that have been measured. Sometimes enough will be known about these typical sources to determine their
uncertainty distributions empirically. In practice, however, expert judgement will often be necessary to define the uncertainty ranges. The pragmatic approach to producing quantitative uncertainty estimates in this situation is to use the best
available estimates; a combination of the available measured data and expert judgement.
Thus, error estimates in AGW modeling are a matter of taste of the experts !!
This is not errors in any scientist’s reckoning, in my not so humble opinion. It is video game playing by the experts.
KSW (11:41:11) :
Have a look at the data from ice cores and discuss whether the heating observed in the last 500 years is any different than the grand sequence of 10.000 years ago, let alone than the complete record.
We should should not jump to conclusions until somebody qualified actually evaluates the paper. Some of the comments on here remind me of of the many baseless comments that came in the wake of Knorr’s recent paper on the “airbourne fraction” of CO2 in the atmosphere.
Moderator – of this is against policy please let me know.
My own pet theory is that the negative feedback loop that everyone is missing is that earth radiance at the poles should go up far far faster than the global temperature. It took me a while to find the right nasa giss data to analyse, let alone rummaging through the dust bins of my mind to find the physics formulas for modeling energy radiance (I gave up and used the internet), but the math supports my theory. WAY too long to post here, but if any of you who actually know what you are talking about want to review, I would appreciate input. If I am wrong I will post the explanation on my blog.
http://knowledgedrift.wordpress.com/
KSW, I read nothing on his page that would change my interpretation of his words. If anything his page reinforces my understanding of what he said. Perhaps you would like to pull some quotes from his page that would support your position that he does not put forth a lower climate sensitivity as a possible reason for the discrepancy noted.
“I couldn’t read all the comments but most of you have displayed such an obvious lack of knowledge on AGW that can be dispelled within 30 seconds of research with credible sources.”
Please provide the scientific process for determining a “credible source”.
“For your information; Stephen Shwartz is no AGW denier.”
Strawman, no one said he denied anything.
“This paper is telling you that physically the amount of warming that has occurred is less than the physics of greenhouse gases should lead to. This is not in any real dispute and doesn’t come as any surprise to anyone that has researched AGW to any level of competence.”
It is telling you more than that, it is telling you that the IPCC’s best estimate climate sensitivity is wrong.
“So, do aerosols have a much larger effect that has been masking the green house effect. Hmmm Dr Shwartz wants to know; Hmmmm, Dr Shwartz poses the question…
The other is that climate sensitivity being lower than current estimates.