Influence of Mineral Dust Aerosol on the Chemical Composition of the Atmosphere PI :

This proposal outlines a program of scientific research and educational development focused on mineral dust aerosol, atmospheric chemistry, and curricular use of satellite data. Mineral dust impacts the chemical composition of the atmosphere by providing a surface for heterogeneous chemistry, and for light scattering and absorption at photolytic wavelengths. We propose to assess the current and potential future influence of mineral dust on the chemical composition of the atmosphere by perfoming simulations of these processes within a global Chemical Transport Model (CTM). Research will focus on reducing uncertainties of the role of mineral dust on atmospheric NOy, SOx, and O3 cycles. Mineral dust provides a surface for heterogeneous removal of H2O2, HNO3, HO2, N2O5, NO3, O3, and SO2 from the atmosphere. This research will first quantify the impact of these processes relative to the impact of other externally mixed aerosols (carbonaceous, sulfate). Second, we will study the influence of mineral dust on photochemistry and assess its regional and seasonal patterns and importance relative to these other aerosols. Although largely of natural origin, emissions of mineral dust are also highly susceptible to enchancement by anthropogenic disturbance such as land use change. Thus the satellite record of the last 20 years will provide crucial insights and constraints on the potential future impacts of mineral dust on the chemistry/climate system. The educational component of the proposal focuses on enhancing undergraduate and graduate exposure to, and experience with, remotely-sensed data. Graduate students will learn to obtain and use remotely-sensed data from the AVHRR, TOMS, and/or SeaWiFs satellites as their term project in my new course, Radiative Processes and Remote Sensing Our department’s large undergraduate survey courses will all be enhanced to present students with new satellite data that illustrates each week’s academic theme.