Seminar

Abstract

Dust and soot degrade visibility in remote parks in the western U.S. (WUS) and their transport and subsequent deposition onto the snow-covered Rockies and Sierra-Nevada mountain ranges accelerates snowmelt and influences the seasonal availability of fresh water to the western states. Understanding the background surface ozone in the WUS is critical for defining a feasible ambient ozone air quality standard. In this talk I examine the sources of soil dust, soot, and ozone in the western mountainous U.S. by analyzing various observations using a global chemical transport model. I focus specifically on constraining the size distribution and source function of dust, open fire and anthropogenic emissions of soot, and fire and lightning contributions to surface ozone as well as the modulating effect of the N. American monsoon on surface ozone in the WUS.