By Garry Lenton
Those heavy downpours that prompt flash-flood warnings and
form lakes on Cameron Street in Harrisburg are increasing in
number, a study released Tuesday by an environmental group
found.
PennEnvironment analyzed 58 years of daily rain data from
3,000 weather stations across the U.S. and found that
"extreme storms" -- those that dump
heavier-than-normal amounts of rain in a 24-hour period --
increased by 41 percent in Pennsylvania and 24 percent
nationally.
The findings bear out predictions by climatologists who say
global warming could lead to an increase in heavy storms,
the study's authors said.
"At the rate we're going, what was once the storm
of the decade will soon seem like just another
downpour," said David Masur, director of
PennEnvironment, a nonprofit, nonpartisan environmental
advocacy group.
The report was released the day before a U.S. Senate
committee was expected to vote on comprehensive global
warming legislation.
It also comes as the state Legislature considers a proposal
to study global warming.
Though global warming is gaining acceptance among voters --
a recent survey by Chris Borick of the Muhlenberg College
Institute of Public Opinion found 70 percent believe it is
happening -- skeptics remain.
Bob Curll, a former meteorologist with the National Weather
Service in Harrisburg, is one of them.
"They are going to use 58 years of data for a planet
that has been around for billions of years? That's a
bunch of b.s.," he said.
But state Rep. Greg Vitali, D-Delaware County, lead sponsor
of a bill passed by the state House in October calling for a
study of global warming's impact on the state, called
the PennEnvironment report "sobering."
"It's one more piece of evidence that we need to
pay attention to this issue," he said.
Researchers used daily precipitation records from the
National Climatic Data Center from 1948 through 2006 to
identify the 59 largest storms for each of 3,000 weather
stations. The storms were then plotted on a timeline, which
showed that frequency increased over time.
The change in frequency was highest in the New England
states, followed by the Mid-Atlantic, which includes
Pennsylvania.
PennEnvironment is using the results to underscore the need
to seek ways to reduce pollution linked to global warming --
such as carbon dioxide emissions.
Pennsylvania's coal-fired power plants and
transportation systems make it the third-largest emitter of
greenhouse gases in the U.S., behind California and Texas.
Curll did not question the report's finding that heavy
downpours are happening more often, but said it doesn't
prove that human activity is to blame.
Climate change "is something that this old ball goes
through every few hundred thousands years," he said.
A 2001 report by the Intergovernmental Panel on Climate
Change predicted that the precipitation in the Northern
Hemisphere would rise due to global warming. The prediction
is based on simple science: Warm water evaporates at a
higher rate, and warm air can hold more moisture than cool
air.
Whether it's global warming or not, more heavy rain
storms mean trouble for residents of the Susquehanna River
basin, which is already the most flood-prone river east of
the Rocky Mountains, according to the Susquehanna River
Basin Commission.
About 30 percent of the basin's population lives along
major rivers. As a result, flooding causes about $150
million in damages a year, according to the SRBC.
Flooding is also the deadliest of all natural disasters,
Masur said.
GARRY LENTON: 255-8264 or glenton@patriot-news.com
