Originally Posted by tofu

(...) And then, a page or two from now, when the inquisition starts and people are shouting, "look there! An unbeliever! A denier is in our midst!! Burn him!!" then I can just cut and paste my comment into a new post where it will make more sense.

Originally Posted by Fortunate

A summary of the 2007 report of the International Panel on Climate Change appears in the August edition of Scientific American. That report, of course, doesn't address the question of warming on other planets, but it does address the issue of whether the sun is responsible for a significant part of global warming. The IPCC presents several lines of reasoning on this question, and each line indicates that the sun is not a central player.

1. The radiative forcing from the sun is presented along with a number of other forcings in a bar graph on p 67. The solar forcing is very small compared to some others and, quite significantly, is accompanied by small error bars.

2. Graphs on page 58, show that when natural forcings only are fed into climate models, the agreement between the graphs and historical temperature records is quite poor, whereas, when anthropogenic forcings are included, the agreement becomes excellent.

3. While the troposphere (lower atmosphere) is heating, the stratosphere (upper atmosphere) is cooling. If solar changes provided the dominant forcing, we would expect the straosphere to heat as well.

4. Two other lines of reasoning are also presented to rule out solar changes as the main driving force, but they did not make as much sense to me, so I will let you read about them in the report if you want. The report is available online at ipcc.ch.