Climate change could snarl U.S. transport: study

Deborah Zabarenko, Reuters 11 Mar 08;

WASHINGTON (Reuters) - Flooded highways, railroads and airport runways are among the transportation snarls looming as the world's climate changes, and officials should plan with this in mind, a U.S. study says.

Modern transportation that runs on fossil fuel has been singled out as a key cause of climate change but the study released on Tuesday by the National Research Council said most transport also is vulnerable to the effects of global warming.

"We're not just concerned about gradual changes in temperatures," said Henry Schwartz, who chaired the panel that wrote the report. "We're mostly concerned about the extremes, the surprises that may come forth.

"We believe ... that the time to begin to address this issue as a routine part of design and operations is now," he told reporters in a telephone briefing.

Specifically, an expected rise in sea levels would hit roads, pipelines and airports in U.S. coastal areas where population is concentrated, Schwartz said.

"As seas rise, plus storm surges, the impacts (to transportation) can be much more severe and extend greater inland than anything we've experienced heretofore," he said.

Schwartz said some the busiest U.S. airports, including New York City's LaGuardia Airport, are in low-laying coastal zones that are vulnerable to flooding from rising seas.

In addition to sea-level rise -- projected to be 7 to 23 inches this century -- other effects of climate change also could hit transportation hard, the report said.

HOT DAYS AND STRONG STORMS

These include an increase in extremely hot days and heat waves, which would affect thermal expansion joints on bridges and cause more rapid degradation of pavement surfaces. Railroad tracks can become deformed in extreme heat and road asphalt can soften.

There also could be limits on constructive activity on transportation projects due to health and safety concerns.

Arctic warming is likely to thaw the permanently frozen ground called permafrost, which means transportation built on it would subside. This includes roads, rail beds, runway foundations, bridge supports and pipelines, such as those that carry petroleum products across Alaska.

On the plus side, the report said there could be a longer transport season and more ice-free ports in northern regions, and the long-sought Northwest Passage from the Atlantic to the Pacific could become more available. Arctic ice melt opened this passage last year for the first time in memory.

The expected increase in intense precipitation could cause more weather-related delays and traffic disruptions, including the flooding of evacuation routes.

More frequent strong hurricanes also are expected to be a consequence of rising global temperatures, and these could cause more frequent interruptions of air service, more frequent emergency evacuations and more debris on roads and rail lines.

These strong storms increase the probability of infrastructure failures. Wave damage and storm surges could have an impact on harbors and ports.

(Editing by Bill Trott)

Global warming to affect transport
Randolph E. Schmid, Associated Press Yahoo News 12 Mar 08;

Flooded roads and subways, deformed railroad tracks and weakened bridges may be the wave of the future with continuing global warming, a new study says.

Climate change will affect every type of transportation through rising sea levels, increased rainfall and surges from more intense storms, the National Research Council said in a report released Tuesday.

Complicating matters, people continue to move into coastal areas, creating the need for more roads and services in the most vulnerable regions, the report noted.

"The time has come for transportation professionals to acknowledge and confront the challenges posed by climate change and to incorporate the most current scientific knowledge into the planning of transportation systems," said Henry Schwartz Jr., past president and chairman of the engineering firm Sverdrup/Jacobs Civil Inc., and chairman of the committee that wrote the report.

The report cites five major areas of growing threat:

• More heat waves, requiring load limits at hot-weather or high-altitude airports and causing thermal expansion of bridge joints and rail track deformities.

• Rising sea levels and storm surges flooding coastal roadways, forcing evacuations, inundating airports and rail lines, flooding tunnels and eroding bridge bases.

• More rainstorms, delaying air and ground traffic, flooding tunnels and railways, and eroding road, bridge and pipeline supports.

• More frequent strong hurricanes, disrupting air and shipping service, blowing debris onto roads and damaging buildings.

• Rising arctic temperatures thawing permafrost, resulting in road, railway and airport runway subsidence and potential pipeline failures.

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.

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.

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 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.