| on May 17, 2008, 11:21 AM E.S.T.
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 Do greenhouse gases help fuel hurricanes, spawning growing legions of stronger storms?
Or is this notion strictly hot air?
Friday, two of the nation's leading climate
scientists traded opposing opinions during a cordial debate on global
warming and hurricanes. The dueling discussion highlighted the closing
day of the Florida Governor's Hurricane Conference in Fort Lauderdale.
The participants were Kerry Emanuel, a
Massachusetts Institute of Technology meteorology professor who links
global warming with increased Atlantic hurricanes, and Chris Landsea, a
National Hurricane Center researcher who disputes this connection.
Both scientists use the same historical climate
statistics and computer models — but they interpret this data in
markedly different fashion.
On one side: Emanuel argues that Atlantic
hurricanes are increasing in frequency and power, probably as a result
of global warming. One of Time's 100 Most Influential People of 2006, his theories gained public recognition in the wake of Al Gore's An Inconvenient Truth.
"There is evidence from several independent
techniques that (hurricane) power dissipation has gone up the last 25
years. Very substantially so in the Atlantic — almost a factor of three
in the past 25 years," he said.
However, on a global scale, Emanuel said no such
upswing in number of hurricanes is apparent. He also said that computer
projections yield "mixed results" on future effects of global warming
on hurricane activity.
Landsea acknowledged that greenhouse gases may
be the major reason that sea-surface temperatures — the engine that
drives hurricanes — have warmed during the last few decades.
But he disputed the accuracy of the historical
data Emanuel used to chart some of his projected trends. Calling
hurricane-monitoring techniques "unreliable, primitive and crude" for
much of the past century, Landsea said the NHC did not even issue
advisories for all weak, short-lived storms as late as the early 1990s.
"It's a bit of a stretch to believe that we
counted them all, and we got how strong they were, and how long they
lasted," he said.
Emanuel said exact historical counts are not of critical importance.
"Why should we put a weak tropical storm that lasts for 12 hours in the same bin as a Katrina?" he asked.
The global-warming hurricane debate is "one of
the most contentious issues in meteorology," said Al Sandrik, a
National Weather Service meteorologist in Jacksonville.
Indeed, clashing studies among hurricane
researchers are bouncing back and forth like a ping-pong ball, said
Stanley Goldenberg, a Miami-based research NOAA meteorologist.
Speculation aside, Landsea said he worries about America's continued migration to hurricane-prone areas, particularly Florida.
"In the next 10 years, we're going to look back
on this and say, 'Well, that was an interesting climate debate about
hurricanes.' But what really is important is this massive population
gain we've got — our horrible vulnerability on our coastal areas,"
Landsea said.
"And I hope we're not going to look back in 10
years and say, 'Oh my God, why didn't we prevent what happened in
Tampa, or prevent what happened in New York?' That's my big concern. Source
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