Large water flows into Lake Mendocino from a storm
Large flows in a tributary to Lake Mendocino during the first winter after the July 2018 fires. Courtesy Scripps Institution of Oceanography

Increasingly intense winter storms have the potential to cause a billion dollars a year in damages in the West, according to an economic analysis by Scripps Institution of Oceanography and the Army Corps of Engineers.

The study analyzed the economic impact of the winter storms that deliver an increasingly large share of rain and snow to California and the West. The study was published Wednesday in the journal Science Advances.

A team led by Scripps postdoctoral researcher Tom Corringham found that flooding has caused nearly $51 billion in damages to western states in the last 40 years. More than 84 percent of these damages were caused by atmospheric rivers, which are long narrow corridors of water vapor in the atmosphere capable of carrying more than twice the volume of Brazil’s Amazon River through the sky.

In some coastal areas of Oregon and Northern California, atmospheric rivers were responsible for over 99 percent of all flood damages, the study found.

“A small number of extreme ARs cause most of the flood damages in the West,” said Corringham, “and even modest increases in intensity could significantly increase their impacts.”

Overall the total flood damage from atmospheric rivers averaged $1.1 billion annually throughout the West.

Scientists expect this climate phenomenon to become more significant as global warming trends increase their intensity, necessitating better forecasting to prevent flooding damage.

“This is a reminder that weather and climate matter,” Corringham said. “Every step we take now to stabilize the global climate system stands to reduce future adverse impacts on our economy.”

Chris Jennewein

Chris Jennewein is Editor & Publisher of Times of San Diego.