WASHINGTON 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
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)