Environment

'Atmospheric Rivers' Wreak Havoc Around The Globe

An "atmospheric river" is a colorful term for a sinuous plume of moisture that travels up from the tropics — a single plume can carry more water than the Mississippi River at its mouth. But new research shows that atmospheric rivers are also among the most damaging weather systems around.

The atmospheric rivers that soaked California this winter did some good — they ended an epic drought in the state.

Waliser studied two decades of storms around the globe at mid-latitudes — that is, outside the tropics. When he focused on the very windiest — the top 2 percent — he found that "atmospheric rivers are typically associated with 30 and even up to 50 percent of those very extreme cases." Atmospheric rivers were also responsible for almost that percentage of the very wettest storms, too.

Atmospheric rivers are famously wet. But atmospheric scientist Duane Waliser has done some new research that shows they're also remarkably windy. Waliser found that winds during an atmospheric river are typically twice the speed of the average storm.