UK Forecasters See More Deluges in Years To Come
Date: 27-Jul-07
Country: UK
Author: Michael Kahn
Wet weather has made the past three months the rainiest early summer in more than 200 years and caused floods across Britain that have forced up to 10,000 people from their homes.
Peter Stott, a climate scientist at the Met Office, said warmer air and water temperatures create more evaporation for a brewing storm to suck up and spit out.
While Britain would normally expect wetter winters and drier summers from global warming, Stott said rising temperatures could also make storms much worse when they did hit.
"The overall signal is generally for a drying trend but nevertheless within that drying trend when it rains it can rain harder," Stott said.
Met Office chief meteorologist Ewen McCallum said the reason for the soggy weather was that the jet stream, essentially a fast-moving ribbon of air, had left clouds and rain hovering over most of Britain.
Normally, the jet stream pushes these low-pressure systems to the north and leaves much of Britain, famous for its changeable weather, with at least a few months of sunshine.
Relief could come in August and perhaps with the start of hurricane season, when strong bursts of energy could clear out these rainy weather systems, he said.
"There are some signs in early August that things might be settling," he told a news conference. "It is not a strong signal for good weather yet."
Insurers have said the combined cost of the June and July floods could top 3 billion pounds ($6 billion). There is also expected to be a heavy impact on agriculture.
Stott also cited a study published in the journal Nature this week showing human activities that spur global warming are largely to blame for changes in rainfall over the last century.
Human-caused climate change has been responsible for higher air temperatures and hotter seas and is widely expected to lead to more droughts, wildfires and floods.
But the study's authors -- who included Stott -- said their research was the first to link it to precipitation changes. Stott predicted this means Britain's future holds severe weather similar to this summer.
"This event can serve as an example of the kind of events we will have in the future," he said.