Massive streams of moisture known as atmospheric rivers traverse the sky, depositing rainfall or snow over land. These phenomena originate in tropical regions where warm conditions elevate water vapor into the atmosphere, as reported by the National Oceanic and Atmospheric Administration (NOAA).
Although these events happen globally, they are particularly impactful on the West Coast of the United States, constituting 30 to 50 percent of annual precipitation. While essential for water resources, they also pose threats like floods and landslides when they unleash powerful storms.
Weak atmospheric rivers occur frequently, but their potent counterparts can carry significant moisture, at times transporting seven to 15 times the Mississippi River’s daily discharge. A study predicts that with rising global temperatures, these atmospheric rivers will become larger, wetter, and more frequent.
(With inputs from agencies.)