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Fifth National Climate Assessment - Read the Report

Advancing modeling of a key source of extreme precipitation (ARTMIP)

Visualization of an atmospheric river bringing moisture from the tropics to the West Coast of the United States on April 6, 2018. Satellites can detect this moisture, and the data can be used to calculate the amount of water that could fall as precipitation under the right atmospheric conditions. Credit: NOAA, using data from the Global Forecast System Model.

Atmospheric rivers are long, narrow regions in the atmosphere that move moist air from the tropics to higher latitudes, producing heavy rain and snow upon landfall. They provide much of the rainfall in the western United States and are frequently associated with extreme weather across large parts of the country. The international Atmospheric River Tracking Method Intercomparison Project (ARTMIP) is seeking to improve understanding of the linkages between climate change and atmospheric rivers. ARTMIP consists of participants from national laboratories, universities, and research centers through funding from DOE, NOAA, NASA, NSF, and international groups. ARTMIP recently completed two major experiments designed to understand how the use of different methods to detect atmospheric rivers in large climate model datasets impacts understanding of their behavior in observations and in future climate simulations (O’Brien et al., 2021; Collow et al., 2022).