Shocker: The Hansen/GISS team paper that says: "we argue that rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases"

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No, this isn’t a joke, it isn’t a fake document, and it isn’t a misinterpretation. It is a paper published by Dr. James Hansen (and the GISS team) in PNAS (Proceedings of the National Academy of Sciences). In the paper (published in 2000, but long since buried) they make these two bold statements (emphasis mine):

..we argue that rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases (GHGs), such as chlorofluorocarbons, CH4, and N2O, not by the products of fossil fuel burning, CO2 and aerosols..

If sources of CH4 and O3 precursors were reduced in the future, the change in climate forcing by non-CO2 GHGs in the next 50 years could be near zero. Combined with a reduction of black carbon emissions and plausible success in slowing CO2 emissions, this reduction of non-CO2 GHGs could lead to a decline in the rate of global warming, reducing the danger of dramatic climate change.

Basically what Hansen is saying is that we should focus on air pollution, and some CO2 reduction, but not exclusively on CO2 alone. This is of course at odds with his famous 350ppm CO2 “safe level” upon which the activist organization 350.org is formed, along with many other pronouncements made by Hansen. I post the abstract and excerpts from the PNAS paper below. Be sure to note the item in red. – Anthony

Global warming in the twenty-first century: An alternative scenario

James Hansen*, Makiko Sato*, Reto Ruedy*, Andrew Lacis*, and Valdar Oinas*§
+ Author Affiliations *National Aeronautics and Space Administration Goddard Institute for Space Studies, Center for Climate Systems Research, Columbia University Earth Institute, and §Center for Environmental Prediction, Rutgers University, 2880 Broadway, New York, NY 10025  Contributed by James Hansen

Abstract 

A common view is that the current global warming rate will continue or accelerate. But we argue that rapid warming in recent decades has been driven mainly by non-CO2 greenhouse gases (GHGs), such as chlorofluorocarbons, CH4, and N2O, not by the products of fossil fuel burning, CO2 and aerosols, the positive and negative climate forcings of which are partially offsetting. The growth rate of non-CO2 GHGs has declined in the past decade. If sources of CH4 and O3 precursors were reduced in the future, the change in climate forcing by non-CO2 GHGs in the next 50 years could be near zero. Combined with a reduction of black carbon emissions and plausible success in slowing CO2 emissions, this reduction of non-CO2 GHGs could lead to a decline in the rate of global warming, reducing the danger of dramatic climate change. Such a focus on air pollution has practical benefits that unite the interests of developed and developing countries. However, assessment of ongoing and future climate change requires composition-specific long-term global monitoring of aerosol properties.

The global surface temperature has increased by about 0.5°C since 1975 (1, 2), a burst of warming that has taken the global temperature to its highest level in the past millennium (3). There is a growing consensus (4) that the warming is at least in part a consequence of increasing anthropogenic greenhouse gases (GHGs).

GHGs cause a global climate forcing, i.e., an imposed perturbation of the Earth’s energy balance with space (5). There are many competing natural and anthropogenic climate forcings, but increasing GHGs are estimated to be the largest forcing and to result in a net positive forcing, especially during the past few decades (4, 6). Evidence supporting this interpretation is provided by observed heat storage in the ocean (7), which is positive and of the magnitude of the energy imbalance estimated from climate forcings for recent decades (8).

The Intergovernmental Panel on Climate Change (IPCC) (4) has considered a range of scenarios for future GHGs, which is further expanded in its Special Report on Emissions Scenarios (9). Yet global warming simulations have focused on “business as usual” scenarios with rapidly increasing GHGs. These scenarios yield a steep, relentless increase in global temperature throughout the twenty-first century (4, 10) with warming of several degrees Celsius by 2100, if climate sensitivity is 2–4°C for doubled CO2, as climate models suggest (4, 1113). These figures can give the impression that curtailment of global warming is almost hopeless. The 1997 Kyoto Protocol, which calls for industrialized nations to reduce their CO2 emissions to 95% of 1990 levels by 2012 (14), is itself considered a difficult target to achieve. Yet the climate simulations lead to the conclusion that the Kyoto reductions will have little effect in the twenty-first century (15), and “30 Kyotos” may be needed to reduce warming to an acceptable level (16).

We suggest equal emphasis on an alternative, more optimistic, scenario. This scenario focuses on reducing non-CO2 GHGs and black carbon during the next 50 years. Our estimates of global climate forcings indicate that it is the non-CO2 GHGs that have caused most observed global warming. This interpretation does not alter the desirability of limiting CO2 emissions, because the future balance of forcings is likely to shift toward dominance of CO2 over aerosols. However, we suggest that it is more practical to slow global warming than is sometimes assumed.

Hansen et al Figure 1: Estimated climate forcings between 1850 and 2000.

Climate forcing by CO2 is the largest forcing, but it does not dwarf the others (Fig. 1). Forcing by CH4 (0.7 W/m2) is half as large as that of CO2, and the total forcing by non-CO2 GHGs (1.4 W/m2) equals that of CO2. Moreover, in comparing forcings due to different activities, we must note that the fossil fuels producing most of the CO2 are also the main source of aerosols, especially sulfates, black carbon, and organic aerosols (4, 23). Fossil fuels contribute only a minor part of the non-CO2 GHG growth via emissions that are not essential to energy production.

Aerosols cause a climate forcing directly by reflecting sunlight and indirectly by modifying cloud properties. The indirect effect includes increased cloud brightness, as aerosols lead to a larger number and smaller size of cloud droplets (24), and increased cloud cover, as smaller droplets inhibit rainfall and increase cloud lifetime (25). Absorbing aerosols cause a semidirect forcing by heating the atmosphere, thus reducing large-scale cloud cover (5). In addition, absorbing aerosols within cloud drops and in interstitial air decrease cloud brightness.

Forcing by atmospheric aerosols is uncertain, but research of the past decade indicates that it is substantial (4, 2628). The aerosol forcing that we estimate (6) has the same magnitude (1.4 W/m2) but a sign that is opposite that of the CO2 forcing. Fossil fuel use is the main source of both CO2 and aerosols, with land conversion and biomass burning also contributing to both forcings. Although fossil fuels contribute to growth of some of the other GHGs, it follows that the net global climate forcing due to processes that produced CO2 in the past century probably is much less than 1.4 W/m2. This partial offsetting of aerosol and greenhouse forcings has been discussed (2931). Offsetting of global mean forcings does not imply that climate effects are negligible.

A corollary following from Fig. 1 is that climate forcing by non-CO2 GHGs (1.4 W/m2) is nearly equal to the net value of all known forcings for the period 1850–2000 (1.6 W/m2). Thus, assuming only that our estimates are approximately correct, we assert that the processes producing the non-CO2 GHGs have been the primary drive for climate change in the past century.

An Alternative Scenario

Hansen et al Figure 5:  A scenario for additional climate forcings between 2000 and 2050. Reduction of black carbon moves the aerosol forcing to lower values.

Let us propose a climate forcing scenario for the next 50 years that adds little forcing (Fig. 5), less than or about 1 W/m2, and then ask whether the elements of the scenario are plausible. The next 50 years is the most difficult time to affect CO2 emissions, because of the inertia of global energy systems, as evidenced by Fig. 4. The essence of the strategy is to halt and even reverse the growth of non-CO2 GHGs and to reduce black carbon emissions. Such a strategy would mitigate an inevitable, even if slowing, growth of CO2. By midcentury improved energy efficiency and advanced technologies, perhaps including hydrogen-powered fuel cells, should allow policy options with reduced reliance on fossil fuels and, if necessary, CO2 sequestration.

Summary

Business-as-usual scenarios provide a useful warning about the potential for human-made climate change. Our analysis of climate forcings suggests, as a strategy to slow global warming, an alternative scenario focused on reducing non-CO2 GHGs and black carbon (soot) aerosols. Investments in technology to improve energy efficiency and develop nonfossil energy sources are also needed to slow the growth of CO2 emissions and expand future policy options.

A key feature of this strategy is its focus on air pollution, especially aerosols and tropospheric ozone, which have human health and ecological impacts. If the World Bank were to support investments in modern technology and air quality control in India and China, for example, the reductions in tropospheric ozone and black carbon would not only improve local health and agricultural productivity but also benefit global climate and air quality.

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So the strategy should be to focus on air pollution, not CO2

Think I made all this up? Read the paper at PNAS here.

(Big hat tip to WUWT reader Nick.)

Backup link in case it disappears like so many other things is here.

Now for the other shocker. This paper was published in the year 2000. So what happened to Hansen since then? He’s totally lost the plot from then, which from my perspective, seems reasonable, and one I could get behind.

Instead we have pronouncements like this:

2008 from a non peer reviewed paper published on Hansen’s personal website

If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm.

2009 in a article in the UK Guardian. Hansen says –

“The trains carrying coal to power plants are death trains. Coal-fired power plants are factories of death.”

And this:

Clearly, if we burn all fossil fuels, we will destroy the planet we know. Carbon dioxide would increase to 500 ppm or more.

May 10th, 2012 Game over on Climate, New York Times op-ed –

Canada’s tar sands, deposits of sand saturated with bitumen, contain twice the amount of carbon dioxide emitted by global oil use in our entire history. If we were to fully exploit this new oil source, and continue to burn our conventional oil, gas and coal supplies, concentrations of carbon dioxide in the atmosphere eventually would reach levels higher than in the Pliocene era, more than 2.5 million years ago, when sea level was at least 50 feet higher than it is now. That level of heat-trapping gases would assure that the disintegration of the ice sheets would accelerate out of control. Sea levels would rise and destroy coastal cities. Global temperatures would become intolerable. Twenty to 50 percent of the planet’s species would be driven to extinction. Civilization would be at risk.

No mention of the other GHG’s, carbon soot, and aersols in that op-ed.

Clearly he seems to have abandoned the idea that seemed so reasonable and workable in his 2000 paper for the idea that CO2 reduction and removal of fossil fuels from the energy equation is the only possible scenario.

I think he was affected by the money, power, and hoopla surrounding Al Gore’s success with the alarming fabrications in An Inconvenient Truth as well as the hoopla and fame associated with the Nobel prize for the 2007 IPCC report. (Added: it is important to note that all of this backpedaling occurred after Hansen’s 1988 Senate testimony  where he and sponsoring Senator Tim Wirth were so sure of the science blaming CO2 saying “that it was 99 percent certain that the warming trend was not a natural variation but was caused by a buildup of carbon dioxide and other artificial gases in the atmosphere.” that they had a thermostat malfunction in the hearing room, it came after Rio Earth Summit 1992, and the subsequent Kyoto protocol. Now Hansen has flip-flopped again with more recent CO2 pronouncements.)

When you go from scientist to arrested activist, the reasonable path just doesn’t get people stirred up. It seems Dr. Hansen has gone over to the dark side of the forcings.

Ask Dr. Hansen’s acolyte Bill McKibben how well reasonable approaches work in all the wailing hippie protests he organizes. You can connect the dots.

UPDATE: graph added, thanks to Joshua Halpern of Howard University who says:

Eli Rabett on 2012/06/03 at 10:42 am says:

That was 2000, this is 2012. As that paper said, the alternative strategy would buy time, not solve the problem. We didn’t follow it and are now running out of time. Twelve years is a while.

REPLY: Yes as noted clearly in red, that was 2000. Twelve years without warming is a while.

http://www.woodfortrees.org/plot/hadcrut3vgl/from:2000/plot/hadcrut3vgl/from:2000/trend

What’s the rush? Meanwhile:

NOAA: Carbon dioxide levels reach milestone at Arctic sites

NOAA cooperative measurements in remote, northern sites hit greenhouse gas milestone in April

– Anthony

UPDATE2: It gets stranger. WUWT reader Jimbo points out in comments, that Hansen wrote a paper blaming soot for the Arctic ice melt, calling it twice as effective as CO2.

Soot climate forcing via snow and ice albedos  James Hansen*  †‡  and Larissa Nazarenko*  †

Plausible estimates for the effect of soot on snow and ice albedos (1.5% in the Arctic and 3% in Northern Hemisphere land areas) yield a climate forcing of 0.3 Wm2 in the Northern Hemisphere. The ‘‘efficacy’’ of this forcing is 2, i.e., for a given forcing it is twice as effective as CO2 in altering global surface air temperature.

Global Warming. Soot snowice albedo climate forcing is not included in Intergovernmental Panel on Climate Change evaluations.  This forcing is unusually effective, causing twice as much global  warming as a CO2 forcing of the same magnitude. This high efficacy  is a straight-forward consequence of positive albedo feedbacks and  atmospheric stability at high latitudes.  Our estimate for the mean soot effect on spectrally integrated  albedos in the Arctic (1.5%) and Northern Hemisphere land areas  (3%) yields a Northern Hemisphere forcing of 0.3 Wm2  or an  effective hemispheric forcing of 0.6 Wm2  . The calculated global  warming in an 1880–2000 simulation is about one quarter of  observed global warming

Source: pubs.giss.nasa.gov/docs/2004/2004_Hansen_Nazarenko.pdf

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Happens sometimes when you have a mild stroke. You suddenly develop obsessive thoughts and/or act out of character. Not joking. Seems to me a very reasonable explanation.

Kurt in Switzerland

This is a shell game.
Kurt in Swizerland

But the models can’t be wrong, can they? This is just a recycling of old ideas with the new flavor of the day. It is still driven in by faith in numeric models not scientific logic. I think it also demonstrates an ignorance of geologic history too.

Hanson: So CO2 is bad, but this other stuff is worse, we must focus on panicking, that is how we can save the world. /s

Ray

Goodbye to anaerobic digesters… those things leak CH4 like crazy. Once again, the farmers will get blamed for the N2O and CH4 their operations emit.

pat

They realize the data has negated CO2 as a major temperature variable. But they still want deindustrialization and relevance. So they slowly change the cue cards.

Twenty percent of the references he cites are papers primarily authored by — oddly enough — Hansen, J.

Babsy

But, but but….what of the “Coal Trains of DEATH”????? Oh, the HUMANITY!
PS: And the boiling oceans?

SPreserv

The backpedalling has started.

REPLY:
No, note the date – Anthony

Luther Wu

a) Somebody did a considerable “tighten up” on Hansen
alternatively
b) Waiting for the other shoe to drop
or
c) He’s lost it

wikeroy

Will James Hansen be put on The Black List now?
REPLY: Note the date, now embellished in red so people don’t miss it – Anthony

Alvin

They are changing horses in mid stream. They realize that even the common man now has a firm grasp on the CO2 debacle and knows it to be a hoax. Now they switch to something that the public most likely has no education on, the other trace GHG’s. The key is to make them own their false CO2 narrative, publish it, and make sure the MSM acknowledge it publicly. Their loss in credibility will help to bury their future efforts. Then we can get back to real science.

Les Johnson

IIRC, Hansen also wrote several papers on aerosols, especially black carbon, and the loss of ice in the arctic and glaciers.
At some point, though, he made a sudden left turn onto the activist freeway.
But, I agree with this approach. Stop the pollution, and there will be benefits other than reducing warming.

alex

This is a quite old paper, isn´t it?
http://www.pnas.org/content/97/18/9875.long
Published online before print August 15, 2000, doi: 10.1073/pnas.170278997
PNAS August 29, 2000 vol. 97 no. 18 9875-9880
REPLY: You, like a few others, missed the two references I made to it being published in the year 2000, so I beefed up the notice to “in your face levels” – Anthony

Hansen’s views on warming continue to “evolve”….. or flip flop, depending upon your political persuasion.

Michael T in Craster, UK

Wow – what is going on with this man? The resurfacing of this paper is not going to be too popular with your EPA, nor with our Department of Energy and Climate Change (nor our Moonbat at the Guardian, nor our Jarvis Cocker “I’m not an expert” airhead). It is surely time that Hansen was brought to task by NASA – it would appear that his mist recent pronouncements (on CO2) might possibly be driven by some political masters..
Thanks
Michael

As of 2:09PM NDT, Hansen hasn’t posted a link to this paper at his website:
http://fromjameshansen.blogspot.com/

markx

Simple strategy. Never, ever admit you were wrong.
Just smoothly brush that all under the rug, then move on to the next stage of the research, and hopefully remain at the forefront.
I’ve seen this in biological sciences. I was at a conference years ago where a lead researcher in one field (probably regarded as the world’s leading expert) was openly mocking what we all thought was some very good research coming out of Europe. Within a year or two he realized the Europeans were correct, smoothly changed horses, did some similar reasearch of his own, and is still the highly respected world expert in the field. At no stage have I heard him apologize or mention that he was, for a time, mistaken.
However, good people, from the point of view of ‘science’, this IS all progress.

“It seems Dr. Hansen has gone over to the dark side of the forcings” – you’re using the humour weapon on them again. Bounder that you are …
Pointman

chris y

My first reaction was that this was a freshly minted, non peer-reviewed paper, because it presents the case for banning the use of natural gas. It also reinforces the call to ban the use of coal. It also presents the expanded regulatory framework as an ‘in addition to banning CO2’, so I don’t see any backing down on demonizing CO2.
In other words-
coal trains are death trains.
natural gas wells are death wells.
natural gas vehicles are death vehicles.
natural gas pipelines are death pipelines.
tar sands are death dirt.
oil shale is death rock.
Has Hansen ever published anything containing verified physics, or has his entire career consisted of parametrized curve-fitting, fiddling with historical temperature measurements within the measurement error bands, extrapolating exponential curves into the future, and advocacy for energy policies?
After all, when he testified in 1988, he already had his own pair of well-used alligator shoes.

TRBixler

Same story, “You are at fault. We are in charge”. Sun? Cosmic influence? Clouds? No, it is humans.

michael hart

Sometimes, once a scientist becomes established as a big “name” in a field, they can often publish opinion-pieces essentially at will, claiming what they like, where they like, when they like, without let or hindrance.
They may become listed as co-authors of papers they have not read, never mind written.
They can publish, and take credit for, speculation that may only later be shown as correct by the work of others. If they are wrong they can be almost immune to criticisms that their theories were not well supported, or were contradicted by the rigorous work of lesser mortals.
Apparent self contradiction provides no obstacle to such occurrences.

Tsk Tsk

Did I read the first figure correctly? Land use changes have a cooling forcing? Really? Would Pielke agree with that? Have our cities grown smaller over the past 150 years?

Talk about a reading skills issue or is it that nobody ever gets past the first paragraph?
Pointman

davidmhoffer

I published a humour piece some years ago that may explain what happened:
Climatologist; I have a system of undetermined complexity and undetermined composition, floating and spinning in space. It has a few internal but steady state and minor energy sources. An external energy source radiates 1365 watts per meter squared at it on a constant basis. What will happen?
Physicist; The system will arrive at a steady state temperature which radiates heat to space that equals the total of the energy inputs. Complexity of the system being unknown, and the body spinning in space versus the radiated energy source, there will be cyclic variations in temperature, but the long term average will not change.
Climatologist; Well what if I change the composition of the system?
Physicist; see above.
Climatologist; Perhaps you don’t understand my question. The system has an unknown quantity of CO2 in the atmosphere that absorbs energy in the same spectrum as the system is radiating. There are also quantities of carbon and oxygen that are combining to create more CO2 which absorbs more energy. Would this not raise the temperature of the system?
Physicist; There would be a temporary fluctuation in temperature caused by changes in how energy flows through the system, but for the long term average… see above.
Climatologist; But the CO2 would cause a small rise in temperature, which even if it was temporary would cause a huge rise in water vapour which would absorb even more of the energy being radiated by the system. This would have to raise the temperature of the system.
Physicist; There would be a temporary fluctuation in the temperature caused by changes in how energy flows through the system, but for the long term average… see above.
Climatologist; That can’t be true. I’ve been measuring temperature at thousands of points in the system and the average is rising.
Physicist; The temperature rise you observe can be due to one of two factors. It may be due to a cyclic variation that has not completed, or it could be due to the changes you alluded to earlier resulting in a redistribution of energy in the system that affects the measurement points more than the system as a whole. Unless the energy inputs have changed, the long term temperature average would be… see above.
Climatologist; AHA! All that burning of fossil fuel is releasing energy that was stored millions of years ago, you cannot deny that this would increase temperature.
Physicist; Is it more than 0.01% of what the energy source shining on the planet is?
Climatologist; Uhm… no.
Physicist; Rounding error. For the long term temperature of the planet… see above.
Climatologist; Methane! Methane absorbs even more than CO2!
Physicist; see above.
Climatologist; Clouds! Clouds would retain more energy!
Physicist; see above.
Climatologist; Ice! If a fluctuation in temperature melted all the ice less energy would be reflected into space and would instead be absorbed into the system, raising the temperature. Ha!
Physicist; The ice you are pointing at is mostly at the poles where the inclination of the radiant energy source is so sharp that there isn’t much energy to absorb anyway. But what little there is would certainly go into the surface the ice used to cover, raising its temperature. That would reduce the temperature differential between equator and poles which would slow down convection processes that move energy from hot places to cold places. The result would be increased radiance from the planet that would exceed energy input until the planet cooled down enough to start forming ice again. As I said before, the change to the system that you propose could well result in redistribution of energy flows, and in short term temperature fluctuations, but as for the long term average temperature…. see above.
Climatologist; Blasphemer! Unbeliever! The temperature HAS to rise! I have reports! I have measurements! I have computer simulations! I have committees! United Nations committees! Grant money! Billions and billions and billions! I CAN’T be wrong, I will never explain it! Billions! and the carbon trading! Trillions in carbon trading!
Physicist; (gasp!) how much grant money?
Climatologist; Billions… Want some?
Physicist; Uhm…
Climatologist; BILLIONS!
Climatologist; Hi. I used to be a physicist. When I started to understand the danger the world was in though, I decided to do the right thing and become a climatologist. Let me explain the greenhouse effect to you…

Jim D

The problem with that strategy was that aerosols have a short lifetime in the atmosphere, so their forcing only increases while the rate of fossil fuel burning increases (accelerates), and stays flat for a constant rate of burning, and decreases as fossil fuel burning decreases. Note that CO2 is long-lived and is still increasing in the meantime, so things are worsened by the reduction of aerosols. This is the Faustian bargain Hansen speaks of regarding sulphate aerosols from fossil fuels, which means basically that you pay for it later unless you continue to accelerate fossil-fuel burning, which is also not practical past the 21st century.

Larry Ledwick (hotrod)

REPLY: You, like a few others, missed the two references I made to it being published in the year 2000, so I beefed up the notice to “in your face levels” – Anthony

So in your face that I did not notice it the first 3 times I scanned the article, (memo not everyone sees red as a high visibility color! In fact I had to look hard to find it by color as in thin lines like this text font it is almost indistinguishable from the black font.)
Like many people who visit here, I do not have the time to read every article in depth, so I scan articles quickly to determine if they are of sufficient interest and worth digging into them in detail.
Otherwise with this a few other forums I would never do anything but eat sleep and read your blog.
Much better if that notice was in bold or even better yet was stated up front in the opening paragraph such as below.
“No, this isn’t a joke, it isn’t a fake document, and it isn’t a misinterpretation. It is a paper published by Dr. James Hansen (and the GISS team) in the year 2000 issue of PNAS (Proceedings of the National Academy of Sciences). In it they make these two bold statements (emphasis mine):”
Larry
REPLY: OK I’ll bold it for people that don’t see red – Anthony

Keith Jackson

As I remember, when this came out the first time (in 2000) there were cries of outrage from the environmental activist community… the very idea that we might get by without destroying the world economy was complete heresy. Hansen was in grave danger of losing his guru status! I have long suspected that this very danger may well have had a hand in shaping his subsequent behavior.

New Strategy, time to dump Global Warming down the Memory Hole. We’re at war with Human Caused Pollution and Land Use Changes now. We’re allies with Climate Change. We’ve always been at war with Human Casued Pollution and Land Use Changes, and we’ve always been allies with Climate Change.
Time for the Two Minutes Hate.
[REPLY:New Strategy“? You did notice the date of the paper, right? -REP]

R Barker

By now the global warming movement has morphed into a pseudo-religion. It really does not matter whether CO2 is bad, good or neutral. The beliefs have been established. Coal is dirty and bad. Alternate energy sources are good regardless of cost or reliability. I doubt if there are any arguements that will make a difference to the believers. Only time and disenchantment with the accumulated failures will erode support. Meanwhile the beneficiaries of the movement will continue to milk what they can get out of it. It is surprising that Hansen was proposing such a thing in 2000 but by then the CO2 gravy train had considerable momentum.

There are indeed some interesting differences between the most probable anthropogenic forcings calculated in Hansen PNAS 2012 and as reported in IPCC AR4 of 2007, most notably CO2 and CH4.
— CO2 down from 1.66 w/m^2 to 1.4 (-16%)
— CH4 up from 0.48 to 0.7 (+46%)
But also significantly Hansen shows net solar forcing of 0.4 w/m^2 vs. AR4’s listing of 0.12.
Taken together these three alone shift forcing away from CO2 by a total of about 3/4 w/m^2 out of an IPCC claimed anthropogenic forcing of 1.6 w/m^2 — almost 50%!

George A

I totally agree that Hansen (and probably Mann) have been seduced by the tantalizing fantasy of their own Nobel Prize.

DirkH

It was not possible to get 1.2 bn USD a year for his employer NASA with the air pollution argument so he got the order to find something more in line with the UNIPCC’s mission, would be my guess.
http://notrickszone.com/2012/04/12/nasa-abdalatis-response-to-50-esteemed-professionals-is-managerial-negligence-an-embarrassment/#comment-92515
http://www.whitehouse.gov/sites/default/files/microsites/ostp/FY12-climate-fs.pdf
GISS – distorting science since 1971 (at least).
http://en.wikipedia.org/wiki/Steve_Schneider
“In 1971, Schneider was second author on a Science paper with S. I. Rasool titled “Atmospheric Carbon Dioxide and Aerosols: Effects of Large Increases on Global Climate” (Science 173, 138–141). ”
Schneider’s prediction: 3.5 degree C cooling through air pollution.

Mike Smith

Maybe Hansen was correct. Even a stopped clock is right twice a day.
Has anyone attempted to study the correlation between the production/presence of non-CO2 greenhouse gasses and the the temperature anomaly? Or is the effect of those man-made non-CO2 greenhouse gases simply swamped by the natural variations in H2O vapor levels?

Matthew

davidmhoffer says:
June 3, 2012 at 10:00 am
I published a humour piece some years ago that may explain what happened:
================================
May I steal this?

Alan the Brit

To quote British actor the late great Trevor Howard, playing the part of Royal Air Force Air-Vice Marshall Park, in that wonderful movie, Battle of Britain, “the bastards are up to something!”
Watch out, that Hansen he is a tricky devil if ever there was one!
Well we got through the first Jubilee celebration finishing in rain here in the UK State of PDRofEU, our poor pointless Consitutional Monarch, with our pathetic government & corrupt politicians, but it was a jolly good show & she is wonderful (God forbid that eco twit of a son of hers succeeds her, he will make a dreadful King!), if only she hadn’t conceded to us joining Europe, it is the only blemish on her remarkable 60 year reign! You colonials really have nothing to compare it with. Damn it we lost the Virginian Colonies, nearly lost Canuckistan, Australia wasn’t revolting afterall apparently it’s very nice with it, we lost Bordeaux through the 100 Years War, we lost the Jewel in the Crown – India! Why don’t we Brits learn to hang to things we owned! Drat it all. 😉

Capo

Hansen wrote a whole chapter about this “shocker” in his book Storms of my Grandchildren. Interested readers can learn a lot about the contexts. A sideline: 10-15 years ago there were rather good chances for smooth solutions, solutions which don’t work in 2012 any more.

Richard deSousa

Hansen and GISS have lost their minds. They’re getting desperate from lack of response from the public and are throwing every thing against the wall hoping something will stick and galvanize people to act in favor of his crazy theories.

That was 2000, this is 2012. As that paper said, the alternative strategy would buy time, not solve the problem. We didn’t follow it and are now running out of time. Twelve years is a while.

REPLY:
Yes as noted clearly in red, that was 2000. Twelve years without warming is a while.

http://www.woodfortrees.org/plot/hadcrut3vgl/from:2000/plot/hadcrut3vgl/from:2000/trend
What’s the rush? – Anthony

davidmhoffer

Matthew says:
June 3, 2012 at 10:37 am
davidmhoffer says:
June 3, 2012 at 10:00 am
I published a humour piece some years ago that may explain what happened:
================================
May I steal this?
>>>>>>>>>>>>>>
Why steal it when you can just make a copy? 😉

Latitude

davidmhoffer says:
June 3, 2012 at 10:00 am
=====================
excellent David!!…………………LOL
So, just like the computer climate games…..no matter what happens they are covered….and can say they said that
warm/cold….wet/dry….snow/rain….drought/flood………………….

nik marshall-blank

I just farted, should I turn myself into the Police?

The last reality was from a parallel universe and anyone who would call it a lie is just totally lacking in nuance and understanding of the issues. And so very……judgemental.
[snip off topic, also off policy – Anthony]

u.k.(us)

Larry Ledwick (hotrod) says:
June 3, 2012 at 10:10 am
“Much better if that notice was in bold or even better yet was stated up front in the opening paragraph such as below.”
===========
Maybe, but let’s not deprive Anthony his fun ?

The Climate Change Chant
Global Warming is real
But it’s no big deal
As any plain fool can see
The waters go up
The waters go down
The levels stay the same at the sea
When I go swimming
I keep thinking
It’s the heat of the day for me
We know it’s not smart
In the pool to fart
Or to jump in the water to pee
The temps go up
The temps go down
I think we can all agree
To shut the hell up
About the climate
It’s as good as climate can be

DirkH

Capo says:
June 3, 2012 at 10:41 am
“Hansen wrote a whole chapter about this “shocker” in his book Storms of my Grandchildren. Interested readers can learn a lot about the contexts. A sideline: 10-15 years ago there were rather good chances for smooth solutions, solutions which don’t work in 2012 any more.”
“good chances for smooth solutions” – I love warmist humour. You mean solar panels worked so much better in 2000?

Babsy

Capo says:
June 3, 2012 at 10:41 am
Are you referring to scientific solutions? Or political solutions?

Claude Harvey

Thanks for the stunt, Anthony. I’d already blasted a “Crazy James Backpedals” message out to everyone I know when I read your subsequent “hints” to responders. My entire day was both “made” and “unmade” in a period of about 20 minutes. I’ll be reading your future pieces with considerable and suspicious attention to detail.

Owen

I would love to see a professional psychiatrist analyze Hansen’s behavior and post the results here. I think the guy may be a sociopath, but I’m no psychiatrist so I’m just guessing. But one doesn’t have to be a professional to know the guy is a NUT.

Bryan A

It is interesting that the second paragraph below “ABSTRACT” states
“The global surface temperature has increased by about 0.5°C since 1975 (1, 2), a burst of warming that has taken the global temperature to its highest level in the past millennium (3). There is a growing consensus (4) that the warming is at least in part a consequence of increasing anthropogenic greenhouse gases (GHGs).”
To me this is saying that you need to go back to 1012 to find either a faster temp rise or a higher temperature.
The Medieval Warm Period lasted from about 950 to 1250 AD during which time the Vikings colonized Greenland. This could not have happened if Greenland didn’t have an adequate length of growing cycle for crops provided by the warmer climate. Many are arguing that the MWP was a localized event that affected only portions of the planet but not on a global scale.
I am curious to see if anyone knows, with all the climate modeling that has been done to date, if any models have been run that can produce a Greenland warm enough to have a sufficiently long growing cycle for crops for the 400+ years that the Vikings colonies were there and still keep the warmth as a fairly localized event.