Department of Energy • Office of Science • Biological and Environmental Research 1 CESD Overview Objective ● Study the impacts of dust on the North American summer monsoon system Approach ● WRF-Chem is used to conduct numerical experiments over 15 years using the MADE/SORGAM aerosol scheme coupled with the GOCART dust emission scheme ● Simulations performed for April- September 1995-2009 at 36 km horizontal resolution with and without dust Impact ● Simulated dust concentration and AOD compared well with observations ● Dust from the U.S. Southwest deserts induces surface cooling of 1 W m -2 and atmospheric heating of 0.4 W m -2 ● Dust heating of 0.3 K day -1 in the lower atmosphere strengthens the Desert Dust Impact on the Summer Monsoon System over Southwestern North America Zhao C, X Liu, and LR Leung. 2012. “ Impact of the Desert Dust on the Summer Monsoon System O ver Southwestern North America ,” Atmospheric Chemistry and Physics, 12, 3717-3731, DOI:10.5194/acp-12-3717-2012. Dust induced diabatic heating over the desert (contours) and precipitation changes over Texas and New Mexico. Dust induced change of zonal and meridional moisture fluxes in the monsoon system.