FLHurricane.com: Lisa Hurricane Again, but Tropics Remain Mostly Quiet still

It wouldn't post on this site either. The Times paper wants you to register so here is the article:

Global Warming Is Expected to Raise Hurricane Intensity

September 30, 2004
By ANDREW C. REVKIN

Global warming is likely to produce a significant increase
in the intensity and rainfall of hurricanes in coming
decades, according to the most comprehensive computer
analysis done so far.

By the 2080's, seas warmed by rising atmospheric
concentrations of heat-trapping greenhouse gases could
cause a typical hurricane to intensify about an extra half
step on the five-step scale of destructive power, says the
study, done on supercomputers at the Commerce Department's
Geophysical Fluid Dynamics Laboratory in Princeton, N.J.
And rainfall up to 60 miles from the core would be nearly
20 percent more intense.

Other computer modeling efforts have also predicted that
hurricanes will grow stronger and wetter as a result of
global warming. But this study is particularly significant,
independent experts said, because it used half a dozen
computer simulations of global climate, devised by separate
groups at institutions around the world. The long-term
trends it identifies are independent of the normal lulls
and surges in hurricane activity that have been on display
in recent decades.

The study was published online on Tuesday by The Journal of
Climate and can be found at
www.gfdl.noaa.gov/reference/bibliography/2004/tk0401.pdf.

The new study of hurricanes and warming "is by far and away
the most comprehensive effort" to assess the question using
powerful computer simulations, said Dr. Kerry A. Emanuel, a
hurricane expert at the Massachusetts Institute of
Technology who has seen the paper but did not work on it.
About the link between the warming of tropical oceans and
storm intensity, he said, "This clinches the issue."

Dr. Emanuel and the study's authors cautioned that it was
too soon to know whether hurricanes would form more or less
frequently in a warmer world. Even as seas warm, for
example, accelerating high-level winds can shred the
towering cloud formations of a tropical storm.

But the authors said that even if the number of storms
simply stayed the same, the increased intensity would
substantially increase their potential for destruction.

Experts also said that rising sea levels caused by global
warming would lead to more flooding from hurricanes - a
point underlined at the United Nations this week by leaders
of several small island nations, who pleaded for more
attention to the potential for devastation from tidal
surges.

The new study used four climate centers' mathematical
approximations of the physics by which ocean heat fuels
tropical storms.

With almost every combination of greenhouse-warmed oceans
and atmosphere and formulas for storm dynamics, the results
were the same: more powerful storms and more rainfall, said
Robert Tuleya, one of the paper's two authors. He is a
hurricane expert who recently retired after 31 years at the
fluid dynamics laboratory and teaches at Old Dominion
University in Norfolk, Va. The other author was Dr. Thomas
R. Knutson of the Princeton laboratory.

Altogether, the researchers spawned around 1,300 virtual
hurricanes using a more powerful version of the same
supercomputer simulations that generates Commerce
Department forecasts of the tracks and behavior of real
hurricanes.

Dr. James B. Elsner, a hurricane expert at Florida State
University who was among the first to predict the recent
surge in Atlantic storm activity, said the new study was a
significant step in examining the impacts of a warmer
future.

But like Dr. Emanuel, he also emphasized that the
extraordinary complexity of the oceans and atmosphere made
any scientific progress "baby steps toward a final answer."

http://www.nytimes.com/2004/09/30/science/30hurricane.html?ex=1097638839
&ei=1&en=3cd89261538d8ab9

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