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The coming megafloods

January 4, 2013

Geologic evidence shows that truly massive floods, caused by rainfall alone, have occurred in California about every 200 years. The most recent was in 1861, and it bankrupted the state. Such floods were most likely caused by atmospheric rivers: narrow bands of water vapor about a mile above the ocean that extend for thousands of miles. Much smaller forms of these rivers regularly hit California, as well as the western coasts of other countries.
Scientists who created a simulated megastorm, called ARkStorm, that was patterned after the 1861 flood but was less severe, found that such a torrent could force more than a million people to evacuate and cause $400 billion in losses if it happened in California today. Forecasters are getting better at predicting the arrival of atmospheric rivers, which will improve warnings about flooding from the common storms and about the potential for catastrophe from a megastorm.

Publication Year 2013
Title The coming megafloods
DOI 10.1038/scientificamerican0113-64
Authors Michael D. Dettinger, B. Lynn Ingram
Publication Type Article
Publication Subtype Journal Article
Series Title Scientific American
Index ID 70040467
Record Source USGS Publications Warehouse
USGS Organization Branch of Regional Research-Western Region