Cloudy forecast for global warming

"All leading climate models forecast that as the atmosphere warms there should be an increase in high- altitude cirrus clouds, which would amplify any warming caused by manmade greenhouse gases," Spencer says in a press release. "That amplification is a positive feedback. What we found in month-to-month fluctuations of the tropical climate system was a strongly negative feedback. As the tropical atmosphere warms, cirrus clouds decrease. That allows more infrared heat to escape from the atmosphere to outer space."