Home arrow English Documents arrow More intense hurricane activity due to global warming
More intense hurricane activity due to global warming Stampa E-mail
From today's Insurance E-News


Four Major Hurricanes, Tropical Storms in Five Weeks of 2004 Raises
Concerns; Stronger Storms - Even If Not More Numerous - Would Challenge
FL, AL, GA, LA, TX, NC and SC

WASHINGTON, D.C.//October 21, 2004///

With four hurricanes and tropical
storms hitting the United States in a recent five-week period, 2004
already is being called "The Year of the Hurricane." But this year's
unusually intense period of destructive weather activity could be a
harbinger of what is to come as the effects of global warming become
even more pronounced in future years, according to leading experts who
participated today in a Center for Health and the Global Environment at
Harvard Medical School briefing.

The recent onslaught of four major tropical weather disturbances -
Charley, Frances, Ivan and Jeanne - that did so much damage in the
United States and nearby Haiti have spurred new questions about the
relationship between hurricanes and global warming. While experts can't
say that climate change will result in more hurricanes in the future,
there is growing evidence and concern that the tropical storms that do
happen will be more intense than in the past. Fueling concerns about the
link between global warming and hurricanes is a new study on hurricane
intensity published on September 28, 2004 in "The Journal of Climate."
The study used extensive computer modeling to analyze 1,300 future
hurricanes and projected a major increase in the intensity and rainfall
of hurricanes in coming decades.

"Global warming may well be causing bigger and more powerful
hurricanes," said James J. McCarthy, a biological oceanographer at
Harvard University and lead author of the climate change impacts portion
of the Intergovernmental Panel on Climate Change's (IPCC) Third
Assessment Report (2001). "Warmer seas fuel the large storms forming
over the Atlantic and Pacific, and greater evaporation generates heavy
downpours. With warmer, saltier tropical seas, the IPCC has projected
larger storms, heavier rainfalls and higher peak winds."

Paul R. Epstein, M.D., associate director of the Center for Health and
the Global Environment at Harvard Medical School, said: "Scientists
cannot say at present whether more or fewer hurricanes will occur in the
future. However, even if the number of storms remained constant, more
powerful hurricanes with stronger winds, higher storm surges, and
heavier downpours would have an even greater potential for damage,
including increased risks to human life and public health, more floods
and mudslides, increased coastal erosion and damage to coastal buildings
and infrastructure. This is the pattern that we already may be seeing
related to the overall increase in extremes."

Precipitation from hurricanes also is seen as being likely to increase,
leading to flooding and mudslides. In addition, hurricane storm surges
could be larger due to sea-level rise from melting ice and snow and the
thermal expansion of ocean waters. In the U.S., the areas at greatest
risk of larger storm surges are low-lying coastal areas along the Gulf
Coast, such as Florida's Panhandle, Alabama's Gulf Shores, southern
Louisiana and eastern Texas. More intense hurricane activity also poses
a risk to such vulnerable sections of the United States as Georgia,
South Carolina and North Carolina.

How would global warming increase the intensity of hurricanes?

One of the consequences of global warming appears to be not only an
increase in sea surface temperature, but a rising of the overall energy
flux at the tropical ocean surface. Some experts think that this
increased surface disequilibrium may lead to more intense tropical
storms. In the Pacific, a large ocean water area two degrees warmer than
average spawned 20 typhoons this season. Eight hit Japan and
meteorologists there have openly attributed that nation's battering to
global warming.

"Human activities are changing the composition of the atmosphere and
global warming is happening as a result," says Kevin Trenberth, head of
the Climate Analysis Section at NCAR and a convening lead author of the
2007 IPCC report for the chapter on observed changes. "Global warming is
manifested in many ways, some unexpected. Sea level has risen 1.25
inches in the past 10 years as a result of warming of the oceans and
glacier melting. The environment in which hurricanes form is changing.
The result was a hurricane in late March 2004 in the South Atlantic, off
the coast of Brazil: the first and only such hurricane in that region.
Several factors go into forming hurricanes and where they track. But the
evidence strongly suggests more intense storms and risk of greater
flooding events, so that the North Atlantic hurricane season of 2004 may
well be a harbinger of the future."

The insurance industry already is reading the signals. From the 1980s
through the 1990s, damages from catastrophes (primarily weather
extremes) rose exponentially - from $4 to $40 billion annually (when
calculated in 1999 dollars) with about one quarter of that amount
insured. In the 1990s, Federal Emergency Management Agency (FEMA)
payouts for disasters quadrupled. Estimates of insured losses from this
year's hurricanes range from $20 to $40 billion.

With the possibility of more problems to come, weather-related property
and casualty costs from extreme events are projected by the UN to reach
$150 billion worldwide this decade. In the US some companies already
have withdrawn coverage from Cape Cod and the southern coast of
Massachusetts. After this brutal hurricane season in Florida, homes and
businesses are likely to face higher deductibles and part of the burden
will fall on taxpayers.

Matthias Weber, senior vice president and chief property underwriter of
the US Direct Americas division of Swiss Re, said: "Not since 1886 have
four hurricanes hit one state in a single season. This year, 22 percent
of Floridians were affected and two million claims generated by
hurricanes and tropical storms. In 2005, we expect the demand for
catastrophe reinsurance to continue to rise. Over the last 10 years
demand has increased about 10 percent per year." CONTACT: Stephanie
Kendall, (703) 276-3254 or skendall@hastingsgroup.com.
Copyright 2000 - 2004 Miro International Pty Ltd. All rights reserved.
Mambo is Free Software released under the GNU/GPL License.

sovrappopolazione, demografia, fame nel mondo, carestie, epidemie, inquinamento, riscaldamento globale, erosione del suolo, immigrazione, globalizzazione, esaurimento delle risorse, popolazione, crisi idrica, guerra, guerre, consumo, consumismo