Climate Feedbacks and Climate Change Denial

The NY Times recently ran an article titled Clouds' Effect on Climate Change Is Last Bastion for Dissenters. What was interesting to me about the article was not only the right wing's reasoning behind climate denial but also the rather sophisticated appeal to climate change feedbacks as a reason not to worry about CO2 emissions. We've come a long way from arguing that GHG emissions don't cause global warming to the "last bastion" of climate change denial, the Iris Effect proposed by Richard Lindzen.

As the directed graph above shows, the right wing has now conceded that CO2 emissions increase global temperature. However, Lindzen argues that warming will increase rain at the equator, depriving cirrus clouds of the moisture necessary for their formation. Since cirrus clouds have the effect of warming the Earth by preventing heat from escaping to space, fewer cirrus clouds could mean a cooler Earth as the Iris opens.

Unfortunately, there is no data to support Lindzen's arguments. Although the feedback effect might exist, it is either (1) too weak to deal with the massive amount of CO2 that is being pumped into the atmosphere as a result of fossil fuel burning or (2) actually a positive loop.

The good news is that, supposedly, this is the right wing's last best argument. The bad news is that we're probably going back to one of the old irrational arguments.