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”
It’s all falling to pieces. Not that it was ever anything like a solid structure.
Tooth fairy took all the bad global warming but I believe the big ship needs to change course because the tooth fairy told me so (with 90% confidence). The shmutz is undoubtedly a factor?
It looks like Spencer’s chart showing twentieth century warming uses a trend line from 2000 forward. It is most likely an extrapolation using the trend line from 2000 to the present. We should all be aware that that trend line has it’s slope effected by the fact that 2000 was a La Nina year and that is why it has any kind of positive trend at all. Spencer should use an ENSO corrected trend line. It will show no rise in temperature.
I did an analysis of the trend since 1998 using both ENSO corrected and uncorrected data. The trend is flat for the last 12 years. I also looked at the accusation that the flat trend was caused by 1998 being an El Nino year. It turned out to be false. And I looked at the explanation that the current 12 year flat trend is due to natural variation. That also turned out to be false. We currently have a 12 year flat trend and there is no explanation for it in natural variability. This is exactly why it is such an important trend and why it falsifies the AGW theory. I give a more in depth explanation here:
http://reallyrealclimate.blogspot.com/2010/01/another-inconvient-truth-for-agw.html
Simple. There is no warming. Small towns’ temperature records show this. Whatever effect CO2 has on the atmosphere, it cannot act arbitrarily nor capriciously. It must act uniformly. And it does not.
http://sowellslawblog.blogspot.com/2010/01/no-warming-from-co2.html
And, large cities must act uniformly – yet San Diego, California, shows a cooling from 1975 to 2009. More evidence that CO2 is not part of the “problem.”
Should the chart show 21st century warming, not 20th century.
tucker (16:41:49)
Should the chart show 21st century warming, not 20th century.
*****************************
I guess I assumed 21st century warming to date. Maybe you meant 20th century as a whole extrapolated. Maybe it should be stated more clearly that that is what was done.
I would have expected the 90% IPCC ‘confidence’ bracket to be symmetric around the ‘Best Estimate’ and thus to include the ‘observation-based estimates’, including zero rise.
“Schwartz’s analysis attributes the reasons for this discrepancy to a possible mix of two major factors: ”
There’s a third possible factor suggested by ice core data. Rising CO2 levels are a result of rising global temperatures and not a cause.
I predict 3 largish equatorial volcanic eruptions in the next 2 years. Coupled with cooling PDO & AMO, this will cause 5 years without Summer. I do this with 90% confidence level.
Why should you believe me?
’cause I said so, so there! 😉
DaveE.
IPCC did not consult me; relied on press interview: Hasnain
“I am unnecessarily being dragged into the controversy. The IPCC did not even consult me or ask me for my research papers for inclusion in the fourth assessment report,” Hasnain, a Fellow with The Energy and Resources Institute, said. ..
“I do not understand why they picked only the interview I had given to New Scientist. I have not mentioned the year 2035 in any of the research papers written by me,” Hasnain said.
http://timesofindia.indiatimes.com/home/environment/global-warming/IPCC-did-not-consult-me-relied-on-press-interview-Hasnain/articleshow/5477806.cms
Reply: Is there some reason you can’t put this comment in a relevant thread? ~ ctm
It is easy to have fun with just an abstract and a press release. I like to do it to.
They are at least asking the right question.
?? Why don’t the official conclusions about warming, that so called consensus, match the observed warming?
They don’t take on the question very aggressively with their three scenarios.
i.e. Either (1) Matters are not too bad, or (2) we are at the tipping point now, or (3) matters are already very bad indeed.
By not mentioning any possibility that matters may not bad at all they don’t challenge the powers that rule climatology or funding or careers.
Charlson says a lot in his remark about the lamppost.
Given the actual trend in temperature is outside the 90% confidence range of the IPCC model, can we now get them to agree that they are 90% confident they are wrong?
““Why Hasn’t Earth Warmed as Much as Expected?”
Simple. Because the models are wrong.”
Not much more to say. CO2 cannot possibly produce the amount of warming predicted. No. Way. The feedbacks are busted in the models. Simple as that.
Dang it! Put a satellite in orbit and MEASURE the energy emitted by the earth.
If the energy emitted by the earth is less that 1/2 the total energy incident upon the earth, then the planet should warm else it should cool if greater than or remain at a constant temp if equal.
What am I missing? Don’t say a brain please. Be kind to the handicapped.
I think I have a fan here at WUWT.
U.N. climatologists play Emily Litella
http://voices.kansascity.com/node/7282
Gilda Radner Nevermind
A little off topic, but apparently the folks at the MSN website aren’t aware of that as indicated by this nonsense: [http://travel.ca.msn.com/international/photogallery.aspx?cp-documentid=23278154 Doomed Destinations] Hope the link works, haven’t included one before.
Look, we have to get a better handle on natural variability. You could argue just as easily that the “next ice age” guys of the mid-70s were right. . . except that C02 overrode it.
No, I don’t believe that either, but if natural variability means that some substantial portion of the last 30 years heating is NV. . . it just as easily could mean that the last 30 years heating is *in spite* of NV cooling factors.
Tho personally I’m more of an AMO/PDO kind of guy, who expects the next ten years to really tell the tale.
…especially with zingers like “Antarctica, has become a popular stopover for cruise ships in the south Atlantic. Studies have shown that both poles are warming at a rate far faster than the rest of the planet, leading to decreased ice thickness and an increase in ice shelf disintegration.” It’s fascinating that they seem to now just ignore reality and go with a full-on marketing approach.
According to Gavin “the matches to observations are still pretty good”
http://www.realclimate.org/index.php/archives/2009/12/updates-to-model-data-comparisons/
Reproducing this figure with the models output, and comparing with “measured” temperature is the correct way of validating (or not) this models.
If a cold period is expected any time soon, temperature could get out of the envelope, that should be enough.
BTW acumulated energy on oceans models proyection is cutted before actual energy estimation, I wonder why.
Dr. Svalgaard
‘I would have expected the 90% IPCC ‘confidence’ bracket to be symmetric around the ‘Best Estimate’ and thus to include the ‘observation-based estimates’, including zero rise.’
Ah well Dr. Svalgaard your problem you see is that you a genuine scientist who believes, as all serious natural philosophers do, in intellectual rigour.
Not fantastical speculation based upon statistical abuse founded upon uncertain and indeed unproven premises.
Still they have made it look good haven’t they? Give the boys another larger research grant.
Kindest Regards
““Why Hasn’t Earth Warmed as Much as Expected?”
Bad models. Too many guesstimates based on false expectations.
And having not got that one right, the next question is now:
How much cooling is to be expected?
Inquiring minds want to know, and they want to know before it cools even further.
mdjackson (16:22:44) : “We will see more of these “soft AGW” papers from climate change experts (the ones who haven’t staked their reputations and their respective organization’s reputations on AGW) until there will be a complete turnaround…”
AGW Lite, anyone?
Slightly O/T, but interesting how the high Arctic temps have seen a sustained decline in temps the first two weeks of this year.
http://ocean.dmi.dk/arctic/meant80n.uk.php
As well there has been a continuous increase in Arctic Ice extent… (Note sidebar)
J2
“The price of permits to emit a ton of carbon dioxide sank 10 percent in London, while oil gained 6 percent in New York since Dec. 7, when 8,000 delegates attended a summit in the Danish capital to prepare for a successor to the Kyoto Protocol, the climate treaty that expires in 2012. Not only did the summit fail to increase regulation on polluters, it also reduced incentives to invest in clean energy.”
Carbon Falls as Climate Failure Is Oil Polluter Boon (Update2)
http://www.bloomberg.com/apps/news?pid=20601081&sid=a7ICxbCZDcyI
Don’t worry, in 30 years at the bottom of the AMO they will be publishing papers about the coming ice age again.