In the National Climate Assessment, published last week, researchers in the United States reported that “large increases in heavy precipitation have occurred in the Northeast, Midwest and Great Plains, where heavy downpours have frequently led to runoff that exceeded the capacity of storm drains and levees, and caused flooding events and accelerated erosion.”
The future, it would seem, has arrived.
Climate is a difficult branch of science, full of ambiguities and uncertainties. But scientists can justly claim to have demonstrated some predictive skill about many of the potential implications of the human release of greenhouse gases.
Their track record actually goes back to 1896, when a Swede named Svante Arrhenius first predicted that emissions of carbon dioxide would cause the planet to warm. It took more than 80 years to be sure he was right. At roughly the same time that realization was taking hold, climate scientists running computer models of the atmosphere began to focus on the likelihood of heavier rains in a future climate.
Many people are still catching up with the science, but it is hard to miss the ubiquity of these heavy rainstorms in recent years.
People in the Florida Panhandle recently had to dodge flash floods after two feet of rain fell in 26 hours. Torrential rains caused a Washington State hillside to collapse and bury a community earlier this year. Tumultuous rainstorms and floods overwhelmed Colorado last year, and sudden floods swept through Nashville in 2010, and Atlanta in 2009.
We’re seeing a pattern here.
In the National Climate Assessment, the experts reported huge increases since the mid-20th century in the amount of precipitation falling in very heavy rainstorms: up 71 percent in the Northeast, 37 percent in the Midwest and 27 percent in the Southeast. The effect was seen on a smaller scale west of the Mississippi River, too, even in parts of the country where the climate is drying out over all.
And of course, there was the flash flood in Maryland yesterday.
I will now go drown my sorrows at the Cantillon Brewery in Brussels. And then fly back to the U.S. on Thursday, contributing significantly to more climate change. Good times. At least this gives me the chance to embed some Dead.