Welcome to The Conservative Cave©!Join in the discussion! Click HERE to register.
0 Members and 1 Guest are viewing this topic.
Why the Earth's surface temperature hasn't warmed as expected over the past decade continues to be a puzzle for scientists. One study out earlier this month theorized that the Earth's climate may be less sensitive to greenhouse gases than currently assumed.Another surprising factor could be the amount of water vapor way up in the stratosphere, according to a new study out Thursday in the journal Science.Water vapor, a potent, natural greenhouse gas, is "a wild card" of global warming, says the paper's lead author, senior scientist Susan Solomon of the National Oceanic and Atmospheric Administration in Boulder, Colo. Solomon was also a co-chair of one of the groups within the Intergovernmental Panel on Climate Change that put out the definitive forecast of global warming in 2007.*snip*Why did the water vapor decrease? "We really don't know," says Solomon, "We don't have enough information yet."The findings are "surprising," says Bill Randel, an atmospheric chemist at the National Center for Atmospheric Research, who was not part of the study. He said it was surprising how big an effect such a very little change in stratospheric water vapor has had on the surface climate.These fluctuations in water vapor could be part of a feedback loop. Although it's known that water vapor in the troposphere increases as the climate warms — and is a major climate feedback that is well simulated in global climate models — in sharp contrast, models do a poor job of simulating water vapor in the stratosphere, according to the paper.But Solomon points out this isn't an indication that predictions on global warming are overstated: "This doesn't mean there isn't global warming," notes Solomon. "There's no significant debate that it is warmer now than it was 100 years ago, due to anthropogenic (man-made) greenhouse gases."
The findings are "surprising," says Bill Randel, an atmospheric chemist at the National Center for Atmospheric Research, who was not part of the study. He said it was surprising how big an effect such a very little change in stratospheric water vapor has had on the surface climate