Global cooling explained: There's less water vapor now

Despite the decrease in water vapor, the study’s authors said, the overall trend is still toward a warming climate, primarily caused by a buildup in emissions of carbon dioxide and other heat-trapping gases from human sources.

“This doesn’t alter the fundamental conclusion that the world has warmed and that most of that warming has to do with greenhouse house gas emissions caused by man,” said Susan Solomon, a climate scientist at the National Oceanic and Atmospheric Administration and the lead author of the report, which appears in the Jan. 29 issue of the journal Science.