—Rising arctic temperatures thawing permafrost, resulting in road, railway, and airport runway subsidence and potential pipeline failures.
(Related story: Arctic Summers Ice Free by 2040, Study Predicts [December 12, 2006])
System Not Built for Change
The nation's transportation system was built for local conditions based on historical weather data, but those data may no longer be reliable in the face of new weather extremes, the report warns.
The committee said proper preparation will be expensive and called on federal, state, and local governments to increase consideration of climate change in transportation planning and construction.
The report notes, for example, that drier conditions are likely in the watersheds supplying the St. Lawrence Seaway and the Great Lakes. The resulting lower water levels would reduce vessel shipping capacity, seriously impairing freight movements in the region, such as occurred during the drought of 1988.
Meanwhile, California heat waves are likely to increase wildfires that can destroy transportation infrastructure.
Small Benefit
The outlook isn't all bad, however.
The report says marine transportation could benefit from more open seas in the Arctic, creating new and shorter shipping routes and reducing transport time and costs.
(Related story: Arctic Melt Opens Northwest Passage [September 17, 2007])
The report was prepared by the Transportation Research Board and the Division on Earth and Life Studies of the National Research Council. The groups are part of the National Academy of Sciences, an independent agency chartered by the U.S. Congress to advise the government on scientific matters.
Sponsors of the study were the Transportation Research Board, the National Cooperative Highway Research Program, the Transportation Department, the Transit Cooperative Research Program, the Environmental Protection Agency, and the Army Corps of Engineers.
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