'Hurricanes feed on warm water'
2008-01-31 10:06
London - British researchers say they have
shown that a half-degree Celsius temperature rise in the
Atlantic ocean can fuel a 40% increase in hurricanes.
The finding by the team from University College London is a
contentious one in the debate over how climate change affects
weather and, especially, storms.
"A 0.5 degree C increase in sea surface temperature is
associated with a 40% increase in hurricane frequency and
activity," the British researchers wrote in their report,
published in the journal Nature on Wednesday.
The team showed ocean warming is directly linked to the
frequency, strength and duration of hurricanes, said Adam Lea,
the research scientist who co-led the study.
The study, which did not look at whether greenhouse gases
linked to global warming played a role in increasing water
temperature, will help scientists better predict how warmer
oceans might affect hurricanes, he added.
"It is important that future climate models are able to
reproduce the relationship between sea surface temperature and
hurricane activity," Lea said. "If you are trying to predict
some of the impacts of global warming you need to have that kind
of sensitivity."
Hurricanes feed on warm water, leading to conventional
wisdom supported by some recent research that global warming
could be revving up more powerful storms.
US researchers, however, last week challenged this view,
saying global warming could reduce the number of hurricanes
hitting the United States with warmer waters resulting in
atmospheric instabilities that prevent storms from forming.
Hurricane seasons
Atlantic storms play a pivotal role in the global energy,
insurance and commodities markets, particularly since the
devastating 2004 and 2005 hurricane seasons, which hammered US
oil and gas production in the Gulf of Mexico.
The British team looked at storms that formed in the
tropical North Atlantic, Caribbean Sea and Gulf of Mexico - a
region that produced nearly 90 percent of the hurricanes that
struck the United States between 1950 and 2005.
Lea and his colleague Mark Sanders at University College
London built a statistical model based on local sea surface
temperature and wind to replicate hurricane activity over the
past 40 years.
This allowed them to remove the effects of wind to determine
the sole impact of sea surface warming.
"We are just linking how much activity you get for a
specific temperature rise," he said.
"The results ... indicate that local sea surface warming was
responsible for 40% of the increase in hurricane activity
relative to the 1950-2000 average between 1996 and 2005," the researchers' report said.