WASHINGTON, DC, July 2, 2008 (ENS) - Climate change will bring an increase in severe storms like the ones responsible for the devastating floods plaguing the U.S. Midwest, experts warned Tuesday. But current government flood forecasts and insurance programs do not consider the effects of global warming, leaving Midwest residents with an incomplete assessment of their flood risks.
"Although no single weather event can be attributed to global warming, it's critical to understand that a warming climate is supplying the very conditions that fuel these kinds of weather events," said Amanda Staudt, a climate scientist with the National Wildlife Federation, NWF.
The frequency of torrential rainstorms in the Midwest has jumped 20 percent since the late 1960s, Staudt said, and large storms that historically would only be seen once every 20 years are projected to happen as often as every five years.
"Global warming is making tragedies like these more frequent and more intense," Staudt told reporters in a telephone briefing. "As climate continues to warm and we have even more moisture in the air, the trend toward increasingly intense weather events will continue."
U.S. officials say the Midwest has seen two 100-year floods in the last 35 years as well as two 500-year floods - one in 1993 and this latest disaster.
Those numbers don't make sense and illustrate the government's flawed flood forecasting, said Nicholas Pinter, a geologist and flood researcher at Southern Illinois University.
"These are not random events," he said. "We are getting a systematic pattern of floods larger and more frequent than estimated by those calculations."
Relying on historical records, flow rates and river elevation, government agencies have consistently underestimated the flooding risks, Pinter said.
The latest study used by agencies, led by the U.S. Army Corps of Engineers, "assumed no natural changes" to the region over time, he said.
It ignored evidence of an increased risk from global warming and failed to consider significant land use changes, new levee construction and modifications to rivers in order to ease navigation, Pinter told reporters.
The Corps' study did include potential flood reduction benefits from dams throughout the Midwest, thereby further underestimating flood risks, Pinter explained.
The faulty estimates, used to set standards for the national flood insurance program, have contributed to the devastation, said David Conrad, a senior resource specialist with the National Wildlife Federation, the largest U.S. environmental organization.
"Many areas have experienced failures of levees that they were led to believe would protect their properties," Conrad said.
The concern has prompted NWF to ask Congress for changes to the National Flood Insurance Reform and Modernization Act, which is currently in negotiations between Senate and House leaders.
Conrad said his organization fears the measures being negotiated offer little that responds to actual changing conditions and are centered on the same land use and building codes standards established 40 years ago.
"These bills look backwards, not forward," he said.
In a letter sent today to key lawmakers, NWF president Larry Schweiger caled on Congress to hold hearings on the issue and mandate improvements to flood forecasting as part of modernizing the flood insurance program.
"In order to ensure that people accurately understand the risks associated with living in certain areas, floodplain maps must be updated using modern climate science," Schweiger wrote. "In addition, methods used to predict the flood heights and frequency of major flood events must be updated to account for climate change, sea-level rise and the predictable future conditions anticipated from land and watershed development."
Schweiger noted that the failure to enact reforms after the 1993 floods, whose record heights were overtopped this year, likely contributed to the recent devastation, "as there was significant rebuilding" in the Mississippi floodplains after 1993.
"While there may have been an expectation that such floods would only happen every 500 years, scientists now warn that climate change will make such floods far more frequent," the NWF chief told lawmakers.
As Congress considers its response to this year's Midwest floods, victims of the disaster are wrestling with how best to move forward.
Joe Wilkinson, president of the Iowa Wildlife Federation, told reporters the devastation "goes a lot deeper than the newspaper shots or the TV videos."
Now that the water has begun to subside, residents must deal with homes and businesses that have sat for days or weeks inundated in contaminated floodwater, he said.
"The people living in those homes now have to go in and clean these things up," Wilkinson said. "The heavy lifting, reconstruction and paperwork are only just beginning."
Wilkinson echoed the call for reforms to flood insurance and new consideration of how the warming climate and conversion of the natural landscape to agriculture and development are making floods more severe.
"We can't just keep doing the same things," he said.
-- By J.R. Pegg, ENS Washington Bureau Chief
Copyright Environment News Service (ENS) 2008. All rights reserved.
