Extreme temperatures are
. We're seeing record-high temperatures across the country, and we're seeing them more often. Two years ago, Dallas-Fort Worth saw
; Wichita Falls, also in Texas, over 100 days. When these heat waves occur, the focus tends to be public health and drought, which is entirely warranted. But the impacts on our transportation system are serious as well, and they affect every conceivable mode of travel.
Cars and Buses:
When high temperatures are sustained for long enough, concrete expands and can buckle, crack, or shatter. This isn't just harmful to the cars, buses, and other vehicles bumping over these holes and cracks; it can be downright dangerous. Besides the potential for irregular roads to cause veering or loss of control, concrete has been known to "
," lifting chunks of concrete and putting those nearby at serious risk.
Heat-buckled freeway segment in North Carolina, from
Asphalt is also at risk of cracking (though usually less severely), but it has its own unique vulnerabilities . It's less stiff than concrete so it deforms more easily in the heat, and can cause roads to end up extremely uneven, unpleasant and sometimes dangerous to drive. In the most extreme heat, asphalt can even
Perhaps the biggest problem with heat-related damage is that it's impossible to predict where the cracks, splits, twists, or explosions will occur. This goes for basically every mode of travel. All you can do is patch them as they happen, try not to shut things down for too long, and hope that no one's injured in the mean time.
Aside from the obvious danger posed by these infrastructure failings, the cost of these constant repairs is high, especially for roads since we have so many. We're already doing a terrible job of keeping our roads in a good state of repair; extreme heat damage is going to absorb more and more of our already-limited routine maintenance budget as the effects of climate change worsen.
Trains and Streetcars:
Just as with asphalt and concrete, steel rails are at risk of overheating and warping. Part of the motivation for this post is today's news that
in the Northeast Corridor in response to the oppressive heat in the region. Consistently high temperatures can cause "
," (or, more euphemistically, a "thermal misalignment") which at their worst can lead to
, and forces operators to slow trains where rail kinks and warping are known to have occurred, or be likely. There are tens of thousands of frequent Amtrak users in the Northeast that are currently having their trips delayed by 10-20 minutes due to the extreme heat. It's good that they're putting safety above speed, but they're going to have to make that trade-off more and more often as temperatures continue to increase. In extreme heat, you can't have both.
Airplanes lose lift at higher temperatures, and
on multiple occasions due to extreme heat. As more regions of the country begin to approach Phoenix-level highs, we may need to expect more cancellations. Also, this:
At Reagan International Airport, photo by
Walking and Bicycling:
This is the saddest of the lot, all the more so because it affects youth and the elderly most severely. We're already seeing it across the country: cities are
during times of extreme heat, discouraging them from getting around on foot or bike. You can't blame the cities, either. Heat exhaustion, heat stroke, and various illnesses made worse by overheating—all are serious concerns and lead to hundreds of deaths and thousands of hospitalizations across the country every year. In California alone, a two-week heat wave in 2006
. According to the Chicago Tribune, "[s]earing temperatures kill more people in the U.S. than hurricanes, lightning, tornadoes, floods and earthquakes combined."
This is especially tragic for its timing. Just as we're finally seeing success in turning the tide back toward healthier, more sustainable lifestyles, tens of millions of people are being instructed to stay indoors and rely on air conditioning to get them through half the year or more. Two of the major causes of climate change—personal vehicles and the energy- and carbon-intensive homes that characterize suburban sprawl—have become our only refuge from the environmental disaster we've engineered. We're spending more time in our homes and cars because our homes and cars have made the climate inhospitable to actual humans.
So what can be done? Not much in the short term, unfortunately. Things are going to get worse before they get better, and as they get worse it will become harder to make the changes we know we need to make. Temperatures will increase, and they'll be high more often, so active transportation will be more of a challenge. Damage to our infrastructure from both extreme heat and extreme storms will sap money away from mitigation and prevention efforts. The obvious response is to invest heavily and rapidly in cleaner energy, and to use that energy more efficiently in our homes, businesses, and transportation systems. I'm not yet hopeful though. In a country where we haven't even come to a political consensus on the theory of climate change, much less the role we play in it, we still have a long way to go.