The Scientific American reports on a paper by Andrew Dessler refuting a paper by Spencer and Braswell. Dessler’s analysis shows:
Clouds change in response to temperature changes. There is no evidence clouds can cause meaningful climate change… “Suggestions that significant revisions to mainstream climate science are required are therefore not supported,” he wrote.
In my words, the story goes Like this. Additional CO2 in the atmosphere traps additional heat from the sun, about 90% of which ends up in the ocean. The ocean is the prime driver of the world’s climate, including changes in cloud cover. There are other lesser drivers but that’s the main story.
In the alternative reality, decreased solar activity lets through more galactic cosmic rays, which increase cloud nucleation, which increase cloud cover, which changes (cools) surface temperature.
OR changes are simply due to internal variability. In any case CO2 has a minor effect and is basically irrelevant.
Skeptical Science looks at the issue here and here. In short Dessler:
found that the heating of the climate system through ocean heat transport was 20 times larger than TOA [top of the atmosphere] energy flux changes due to cloud cover over the period in question.
There’s more, with links, at Deltoid and here. Skeptical Science also has a post on denialoshere reaction and an earlier post on the net feedback from clouds. Continue reading Climate clippings 43