Alexa

Water vapor drop may have led to warming slowdown

Water vapor drop may have led to warming slowdown

The slowdown in global warming in the last few years may have been caused by a decline in water vapor in the stratosphere, a new report suggests.
While climate warming is continuing _ the decade of 2000 to 2009 was the hottest on record worldwide _ the increase in temperatures was not as rapid as in the 1990s.
Balloon and satellite observations show the amount of water vapor in a layer about 10 miles (16 kilometers) high declined after 2000. The stratosphere extends from about eight to 30 miles (48 kilometers) above the Earth's surface.
The reason for the decline is unknown, according to researchers led by Susan Solomon of the National Oceanic and Atmospheric Administration. They report their findings in Thursday's online edition of the journal Science.
Water vapor is a potent greenhouse gas, and its decline in the stratosphere would reduce the rate of global warming expected from other gases such as carbon dioxide, the researchers said.
According to the researchers, water vapor enters the stratosphere primary from air rising in the tropics.
___
On the Net:
http://www.sciencemag.org


Updated : 2021-03-01 13:04 GMT+08:00