Correction: A reader has pointed out that the paper is an analysis of some models which shows albedo, often claimed by alarmists as the primary Arctic climate driving factor, is not the number one Arctic amplifier after all, as skeptics have long maintained. The paper itself says nothing about the integrity of models, and thus the title above has been changed.
Spiegel here reports on a paper appearing in Nature titled: Arctic amplification dominated by temperature feedbacks in contemporary climate models – by Felix Pithan and Thorsten Mauritsen of the Max Planck Institute for Meteorology in Hamburg.
Climate science often claims that nowhere is the climate changing faster than in the Arctic. Scientists have often attributed these changes to albedo effects. But the new study finds that amplification can also occur without changes in albedo. Spiegel writes that the authors, based on an analysis of models, found the largest contribution to Arctic amplification comes from a temperature feedback, where at lower latitudes warmed air rises faster and more easily than it does in the Arctic. As the surface warms, more energy is radiated back to space in low latitudes than in the Arctic. Thus polar air radiates less heat out into space than tropical air does.
In a nutshell, the two authors have found that the primary amplification factor is the “stolidness” of Arctic air, and less so albedo. In the Arctic warmed air tends to remain more at the surface and heat does not escape as readily.
To balance out the radiation budget at an ambient temperature of 30°C, an increase of 0.16° is enough. However at minus 30°C, an increase of 0.31 °C would be needed, i.e. almost double, which gives Pithan und Mauritsen cause for thought. According to their calculations the lower start temperature in the Arctic is an important reason for the more rapid temperature increase in the Arctic compared to the tropics.”
They found that the surface albedo feedback is only the second main contributor to Arctic amplification, and that other contributions are substantially smaller or even oppose Arctic amplification.
This casts many of the assumptions made in earlier climate models deep into doubt. It’s back to the drawing board (again) for the modelers.
For a science that is more than 95% certain, we sure do see quite a steady stream of surprises with each passing day.
UPDATE: As reader Kurt points out, the claims made by the authors are based on “model simulations”. And we know that over 97% (114/117) of the models have completely missed the barn since 2000. So if models cannot tell us the temperature, what could they possibly say about the mechanisms driving climate?