Global warming in Europe
Water vapor feedback is rapidly warming
WASHINGTON -- A new report indicates that the vast majority of the rapid temperature increase recently observed in
Elevated surface temperatures due to other greenhouse gases have enhanced water evaporation and contributed to a cycle that stimulates further surface temperature increases, according to a report in Geophysical Research Letters.
The research could help to answer a long-debated Earth science question about whether the water cycle could strongly enhance greenhouse warming.
Swiss researchers examined surface radiation measurements from 1995 to 2002 over the Alps in
The authors, led by Rolf Philipona of the
The researchers analyzed temperature and humidity changes over
They suggest that their combined observations indicate that the region is experiencing an increasing greenhouse effect and that the dominant part of the rising heat emitted from the Earth's atmosphere (longwave radiation) is due to water vapor increase.
After examining increased cloud cover to the north of the
The strong increase of longwave radiation is shown in the study to be due to increasing cloudiness, rising temperature, rising water vapor, and above all to long-lived manmade greenhouse gases. The scientists' radiation measurements in the
Above all, their measurements demonstrate strong water vapor feedback that rapidly warms Central and
http://www.eurekalert.org/pub_releases/2005-11/agu-wvf110805.php