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Another transportation worry in Minnesota: climate change

As if Minnesota didn’t have enough transportation headaches, a major study released today by the National Research Council says that climate change poses serious problems for transportation systems nationwide.First, the report summarily dismisses an

As if Minnesota didn’t have enough transportation headaches, a major study released today by the National Research Council says that climate change poses serious problems for transportation systems nationwide.

First, the report summarily dismisses any doubt that climate change is real:  “Even if drastic measures were taken today to stabilize or totally eliminate [green house gas] emissions, the effects of climate change would continue to be experienced, and U.S. transportation professionals would have to adapt to their consequences.”

So the choices are to prepare in a measured way now or in a panic in the future. Ignoring the problem is not a real option.

With stakes high for the safety of human lives as well as for the economy, the report urges action now and calls upon the federal government to take the lead. But state and local officials can and should heed the advice now, said the study titled “Potential Impacts of Climate Change on U.S. Transportation.”

Taken as a whole, the challenge is so immense, it’s hard to comprehend. Think of every transportation amenity in Minnesota alone — highways, bridges, railways, airport runways, locks and dams on the Mississippi and other rivers, canals connecting lakes and much more.

Nearly all of it has been designed and built for our local weather and climate conditions based on historical temperature and precipitation data. Now, with temperature and precipitation patterns changing, expectations may no longer be reliable for how long a bridge, a dam or a road might hold up.

Five key changes

What’s true in Minnesota, of course, is true nationwide. The report focuses on five changes (PDF) that are important to transportation: more sweltering hot days, Arctic temperatures rising to melt the permafrost, rising sea levels, heavier downpours of precipitation and more intense hurricanes.

The report says coastal areas may be most vulnerable because of rising sea levels and surges propelled by intense storms.

But the Midwest doesn’t escape the consequences. It faces not only warmer weather, but more precipitation extremes — drier some places at some times; wetter elsewhere at other times.

Among other findings, the report says:

• Watersheds supplying the St. Lawrence Seaway and the Great Lakes, as well as the Upper Midwest river systems, are likely to experience drier conditions, resulting in lower water levels and reduced capacity to ship agricultural and other bulk commodities, although a longer shipping season could offset some of the adverse economic effects.

• Heat waves could lead to more frequent buckling of pavements and misalignment of rail lines.

• More severe storms with intense precipitation could increase flooding, such as the storms that plagued the Midwest during the 1993 flooding of the Mississippi and Missouri Rivers. Flooding can knock out barge operations on the river itself, rail operations on rights-of-way adjacent to the river, and even highway approaches to bridges.

I-35W bridge cited
Minnesotans may be more sensitive to transportation deficiencies than Americans elsewhere because of the deadly collapse of the I-35W bridge in Minneapolis in August.

Bridges are particularly vulnerable, the report said, because thermal expansion in their joints will change with the intense heat that warming will bring. Without naming causes, the study cites the collapse of the I-35W bridge as evidence of the need for better technologies to monitor bridge conditions.

The report calls for tough-minded new thinking about transportation investment. As politically painful as it may be, the reality is that some beautiful coastal roads and useful riverside railways may inevitably become casualties of climate change.

It urges the federal government to create a broad-based action plan, including a clearinghouse for information on transportation and climate change as well as a research program to re-evaluate existing design standards and develop new standards. The National Flood Insurance Program also needs updating, it said.

Local governments should begin now, the report said, to identify critical infrastructure that is particularly vulnerable.