Atmospheric Rivers and Precipitation Extremes under a Changing Climate

This study uses the Weather Research and Forecast (WRF) model as a regional climate model and Coupled Model Intercomparison Project Phase 5 Earth System Models (ESMs) as initial and boundary conditions to perform downscaling. The spatial resolution is 12km, and the domain covers most of North America. The analysis focuses on comparing precipitation extremes in future climate (2045-2054 and 2085-2094) using the “business as usual” high emissions scenario compared to a historical period (1995-2004). Results show that in future there is a large increase in the projected frequency of extreme precipitation events over the entire CONUS and a decrease in median precipitation days. Moreover, most regions show an increase of number of dry days for the future scenarios. We will look at atmospheric rivers (AR) calculated using our model output to investigate how the AR changes in a changing climate and how it affects the precipitation change.