Monday, May 16, 2011

James Hansen admits man-made global warming has been greatly exaggerated by climate models

As just pointed out by an astute and disillusioned young climate scientist, James Hansen, the high priest of the global warming religion and defender of creation has recently produced a non-peer-reviewed paper finding that the net man-made effects on climate have been greatly exaggerated by computer models. Hansen claims most climate models have underestimated the cooling effect of man-made aerosols via cloud changes, although the fine print in the paper admits they really have no idea what is causing the cloud changes and resulting cooling effect. Hmmm, possibly the cosmic ray theory of Svensmark et al? Hansen also references estimates for climate sensitivity pulled out of the air by his brainwashed grandchildren in the amusing paper (p. 3).

Earth's Energy Imbalance and Implications

James Hansen (1), Makiko Sato (1), Pushker Kharecha (1), Karina von Schuckmann (2)

((1) NASA Goddard Institute for Space Studies and Columbia University Earth Institute, (2) Centre National de la Recherche Scientifique)

(Submitted on 5 May 2011)

Improving observations of ocean temperature confirm that Earth is absorbing more energy from the sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.59 \pm 0.15 W/m2 during the 6-year period 2005-2010, provides fundamental verification of the dominant role of the human-made greenhouse effect in driving global climate change. Observed surface temperature change and ocean heat gain constrain the net climate forcing and ocean mixing rates. We conclude that most climate models mix heat too efficiently into the deep ocean and as a result underestimate the negative forcing by human-made aerosols. Aerosol climate forcing today is inferred to be -1.6 \pm 0.3 W/m2, implying substantial aerosol indirect climate forcing via cloud changes. Continued failure to quantify the specific origins of this large [negative] forcing is untenable, as knowledge of changing aerosol effects is needed to understand future climate change. A recent decrease in ocean heat uptake was caused by a delayed rebound effect from Mount Pinatubo aerosols and a deep prolonged solar minimum. Observed sea level rise during the Argo float era can readily be accounted for by thermal expansion of the ocean and ice melt, but the ascendency of ice melt leads us to anticipate a near-term acceleration in the rate of sea level rise.

Sorry Jimbo, near-term sea level rise is decelerating  


  1. I wonder if the "man made" aerosols he refers to are the "chem trails" being sprayed over the United States by military jets? Google this and see OUR government is doing secret geo engineering WITHOUT our knowledge or consent.

  2. @Anonymous - No, that is NOT what he means by man-made aerosols. "Aerosols" are a generic term in climate science for very small solid particles, such as very fine soot.

  3. Does the author here have ANY idea what Trenberth meant when he talked about the "travesty" of not being able to account for the lack of warming? Obviously, he does not. Or he does not care.

    What Trenberth was saying - you can look it up because he explains what he meant - is that, because funding was cut by the Bush administration for a satellite that would allow scientists to follow the energy flow from year to year and thereby understand why air temps go up and down erratically (while trending upward), we are NOT able to explain these annual ups and downs. The point is that the typical temp record that we see as graphs is AIR temp, but global warming warms air, land and measuring only one does not give the whole warming picture. When more energy flows into the oceans, eg, less goes into the air which warms less that year. The "travesty" is that we cannot follow these energy flows and are therefore not able to explain the detailed ups and downs of the air temp record.

    Confusing Trenberth's statement for an indictment of the science of global warming is a dead sure indication that the author has no idea what s/he is writing about.

  4. Larry,

    Trenberth is convinced there is "missing heat" that our observing system can't detect, but fails to consider the null hypothesis that the heat was simply not there to begin with. Suggest you read all the comments on this post at Judith Curry's blog:

  5. I am fairly new to learning about this climate stuff but... what I read from this limited snippet was this..

    Learning that the models are set to mix too efficiently, caused Hansen to have to rejig the numbers for aerosols forcing because?? because the models dont give the answers you want otherwise hence the phrase ' Aerosol climate forcing today is inferred to be -1.6 \pm 0.3 W/m2'. INFERRED meaning fudged.?

  6. It reads a bit like "Yes, we don't really know, but can still think of a reason why it's going to be worse than we thought." As usual.