Important new study from AWI: Cooling discovered in Antarctica, enabled by Carbon Dioxide
I’m sure our alarmist friends will be ready to dismiss this…but, it looks pretty solid. Tommy Tyrberg sends in this tip. He writes:
Here is a very interesting paper from the Alfred Wegener Institute for Polar and Marine Research (AWI) which seems to have very largely escaped notice.
In short the author shows convincingly that in Central Antarctica where the tropopause is very low and ill-defined, and there is often a strong ground inversion, increased CO2 actually has a net cooling effect, since it will normally result in LWIR radiation to come from a higher altitude with a higher radiation temperature. The title is extremely discreet by the way.
It would seem that this would be a very elegant explanation why Antarctica is completely failing to become warmer, so I presume the reason it has not made any waves is that it also implies that the EAIS is enormously stable with respect to higher CO2 levels. And since the cold catabatic winds from central Antarctica also largely control coastal antarctic climate and the production of Antarctic Bottom Water from coastal polynyas the results have global significance as well.
Hypotheses behind the thesis
The occurrence of emission maxima at TOA in the absorption bands of GHGs means, that, from a top of atmosphere perspective, the presence of GHGs causes a surplus of energy loss into space. Taking the difference between surface and TOA emission as greenhouse effect, this yields a negative GHE being observed over Antarctica. Furthermore, when considering increasing concentrations of GHGs, particularly CO2, this phenomenon should yield an increase in thermal
emission. This is opposite to what is generally known to result from increasing concentrations of GHGs.
In section 1.5 it has been demonstrated, that global warming during the last decades has not been
proven to occur over the highest elevated areas of Antarctica. There are even indications, that
parts of the continent might have experienced slight cooling. One cause of this non-warming might
be the inverted effect of GHGs on the long-wave radiative emission to space over central
Here is a longer and more detailed version from the Author’s PhD dissertation:
CO2 is the strongest anthropogenic forcing agent for climate change since pre-industrial times. Like other greenhouse gases, CO2 absorbs terrestrial surface radiation and causes emission from the atmosphere to space. As the surface is generally warmer than the atmosphere, the total long-wave emission to space is commonly less than the surface emission. However, this does not hold true for the high elevated areas of central Antarctica. For this region, it is shown that the greenhouse effect of CO2 is around zero or even negative. Moreover, for central Antarctica an increase in CO2 concentration leads to an increased long-wave energy loss to space, which cools the earth-atmosphere system. These unique findings for central Antarctica are in contrast to the well known general warming effect of increasing CO2 . The work contributes to explain the non-warming of central Antarctica since 1957.
Antarctic Specific Features of the Greenhouse Effect : a Radiative Analysis Using Measurements and Models | Request PDF. Available from: https://www.researchgate.net/publication/279399598_Antarctic_Specific_Features_of_the_Greenhouse_Effect_a_Radiative_Analysis_Using_Measurements_and_Models [accessed Jul 15 2018].
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