Peter Brannen in The Atlantic:
Humans have begun an international project to move water around the world, far more ambitious than any network of aqueducts or hydroelectric dams ever constructed or conceived. The drivers of this global system are billowing vapors, which trap heat and propel the world’s water faster and farther around the globe. The first results of this project may already be seen in the outrageous rainfall totals of storms like Hurricane Harvey, or in landslides on remote mountain hillsides, and even in the changing saltiness of the oceans.
The Earth system is getting warmer. Water is evaporating faster. There’s more of it in the air. It’s moving through the system faster. As a result, the coming centuries will play out under a new atmospheric regime, one with more extreme rain, falling in patterns unfamiliar to those around which civilization has grown.
“Basically the idea is that as the climate warms there’s more energy in the atmosphere,” says Gabriel Bowen, a geochemist at the University of Utah. “That drives a more vigorous water cycle: Evaporation rates go up, precipitation rates go up—there’s just more water moving through that cycle faster and more intensely.”
For each degree Celsius of warming the atmosphere is able to hold 6 percent more water. For a planet that’s expected to warm by 4 degrees by the end of the century, that means a transition to a profoundly different climate.
“Rainfall extremes have increased in intensity I think at every latitude in the northern hemisphere,” says Massachusetts Institute of Technology climate scientist Paul O’Gorman.
More here.