Hurricane season
Hurricanes 'to get stronger'
Alok Jha
Hurricanes are likely to get more extreme as a result of climate change, say scientists.
Computer models of the Earth's water cycle suggest that hurricanes will intensify as warmer temperatures draw more ocean water into the atmosphere.
The research follows a record number of hurricanes affecting
Kevin Trenberth, a researcher at the National Centre for Atmospheric Research in
Most of the hurricanes that strike the
"Over the 20th century, water vapour over the global oceans increased by 5% and that probably relates to about a 5% increase in intensity and probably a 5% increase in heavy rainfalls," says Dr Trenberth, whose research is published today in Science. "That relates directly to the flooding statistics."
Present models suggest a 7% increase in the moisture in the atmosphere for every degree celsius that the earth warms. As the carbon dioxide in the atmosphere increases and global temperatures rise, so the amount of water in the atmosphere goes up.
However, the effect of climate change on hurricane numbers and landfalls is uncertain, said Dr Trenberth.
Models disagreed on how global warming might affect the wind sheer that can either support or discourage hurricane formation.
The number of hurricanes and typhoons tends to hold steady from year to year. When activity increases in the
"There is no sound theoretical basis for drawing any conclusions about how anthropogenic climate change affects hurricane numbers or tracks, and thus how many hit land," said Dr Trenberth.
· Temperatures across much of the country are likely to hit highs of
Source: the Guardian
http://www.guardian.co.uk/naturaldisasters/story/0,7369,1508554,00.html