Atmospheric Rivers

Atmospheric rivers are corridors of moisture that provide essential water resources to the western U.S. but also cause severe flooding and landslides. Climate change is increasing the intensity and moisture content of these storms, which is projected to raise annual flood damages in the western U.S. to between $2.3 and $3.2 billion by 2090. While a series of atmospheric rivers in early 2023 significantly reduced drought coverage in California, the trend toward warmer storms is reducing snowpack and increasing the risk of compounding climate hazards.

• Atmospheric rivers are critical to the global water cycle, transporting 90% of the water vapor across mid-latitudes. In California, they can provide up to 50% of the total annual streamflow and precipitation during winter and fall.
• While atmospheric rivers can alleviate drought—breaking up to 74% of droughts in the Pacific Northwest and West Coast between 1950 and 2010—they also drive the majority of flood-related economic losses in the western U.S. From 1978 to 2017, they caused an estimated $42.6 billion in flood damages across 11 western states.
• Climate warming increases the moisture-holding capacity of the air by 4% for every 1°F of warming. Since 1970, the U.S. has warmed by 2.6°F, allowing the atmosphere to hold approximately 10% more moisture, which may increase total precipitation during California atmospheric river storms by up to 40% on the windward western slopes of the central and southern Sierra Nevada.
• Warming trends are shifting precipitation from snow to rain, reducing the snowpack that serves as a vital water source for the West. In the Sierra Nevada, five of the last ten years saw April 1 snowpack levels below 50% of the historic average, though 2023 bucked this trend with snowpack more than double the statewide average.
• Continued high rates of carbon pollution could cause annual flood damages from atmospheric rivers in the western U.S. to reach $2.3 to $3.2 billion by 2090, which is double or triple the historical average.

APA

AghaKouchak, A., Medellín-Azuara, J., & Solis, S. S. (2023). Atmospheric Rivers. Climate Central. https://www.climatecentral.org/climate-matters/atmospheric-rivers-2023

Chicago

AghaKouchak, Amir, Josué Medellín-Azuara, and Samuel Sandoval Solis. Atmospheric Rivers. Climate Central, 2023. https://www.climatecentral.org/climate-matters/atmospheric-rivers-2023.

Wikipedia

{{cite report |last1=AghaKouchak |first1=Amir |last2=Medellín-Azuara |first2=Josué |last3=Solis |first3=Samuel Sandoval |title=Atmospheric Rivers |publisher=Climate Central |date=29 March 2023 |url=https://www.climatecentral.org/climate-matters/atmospheric-rivers-2023 |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{aghakouchak2023atmospheric, author = {AghaKouchak, Amir and Medellín-Azuara, Josué and Solis, Samuel Sandoval}, title = {{Atmospheric Rivers}}, institution = {Climate Central}, year = {2023}, month = mar, url = {https://www.climatecentral.org/climate-matters/atmospheric-rivers-2023}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }