Rainfall

Hurricane Ian hit Florida in September 2022 as one of the United States’ most powerful hurricanes on record, and it followed a two-week string of massive, devastating storms around the world. A few days earlier in the Philippines, Typhoon Noru gave new meaning to rapid intensification when it blew up from a tropical storm with 50 mph winds to a Category 5 monster with 155 mph winds the next day. Hurricane Fiona flooded Puerto Rico, then became Canada’s most intense storm on record. Typhoon Merbok gained strength over a warm Pacific Ocean and tore up over 1,000 miles of the Alaska coast. Major storms hit from the Philippines in the western Pacific to the Canary Islands in the eastern Atlantic, to Japan and Florida in the middle latitudes and western Alaska and the Canadian Maritimes in the high latitudes. A lot of people are asking about the role rising global temperatures play in storms like these. It’s not always a simple answer....

Atmospheric rivers – those long, narrow bands of water vapor in the sky that bring heavy rain and storms to the U.S. West Coast and many other regions – are shifting toward higher latitudes, and that’s changing weather patterns around the world. The shift is worsening droughts in some regions, intensifying flooding in others, and putting water resources that many communities rely on at risk. When atmospheric rivers reach far northward into the Arctic, they can also melt sea ice, affecting the global climate. In a new study published in Science Advances, University of California, Santa Barbara, climate scientist Qinghua Ding and I show that atmospheric rivers have shifted about 6 to 10 degrees toward the two poles over the past four decades. Atmospheric rivers on the move Atmospheric rivers aren’t just a U.S West Coast thing. They form in many parts of the world and provide over half of the mean annual runoff in these regions, including the U.S. Southeas...