WxTalk Webinar #87


Webinar #87 - October 2023

Atmospheric Rivers (2023 Update)

Marty Ralph
Director, Center for Western Weather and Water Extremes
UCSD/Scripps Institution of Oceanography
La Jolla, California


Atmospheric Rivers (AR) are relatively narrow regions in the atmosphere that are responsible for most of the horizontal transport of water vapor outside of the tropics. While ARs come in many shapes and sizes, those that contain the largest amounts of water vapor, the strongest winds, and stall over watersheds vulnerable to flooding, can create extreme rainfall and floods. However, not all ARs cause damage – most are weak, and simply provide beneficial rain or snow that is crucial to water supply.  In fact, they can also be drought busters.

This presentation will provide a brief history of the emergence of understanding of atmospheric rivers as a phenomenon, and as a key factor in precipitation in many regions.  An emphasis will be placed on lessons learned from studies in the Western US, with highlights from the emerging exploration of ARs as important elsewhere.  Efforts to better monitor and predict ARs will also be summarized.

View the Webinar by clicking here:
View Marty's presentation slides here  



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