Evaluation of Modeled SO2 in the UTLS Region with Both Satellite and Aircraft Data

Friday, 18 December 2015: 17:30
3002 (Moscone West)
Qian Tan, Bay Area Environmental Research Institute Moffett Field, Moffett Field, CA, United States, Mian Chin, NASA Goddard Space Flight Center, Greenbelt, MD, United States, Huisheng Bian, NASA Goddard Space Flight Ctr, Greenbelt, MD, United States, Gao Chen, NASA Langley Research Ctr, Hampton, VA, United States, Valentina Aquila, Johns Hopkins University, Earth and Planetary Science, Baltimore, MD, United States and Amanda Benson Early, NASA Langley Research Center, Hampton, VA, United States
Both ground based and satellite based measurement showed stratospheric aerosols exhibit some trend in the post Pinatubo era. Various reasons have been proposed to explain this observation. We evaluate the global aerosol model simulation in the UTLS region with multiple observation datasets with a focus on SO2, the important aerosol precursor. Both online and offline versions of GOddard Chemistry Aerosols Radiation Transport (GOCART) model, which is driven by NASA Goddard Earth Observing System Model Version 5, i.e. GEOS-5, meteorological condition are used in this evaluation. When compared to available satellite retrieval of SO2. GOCART model is able to capture the volcanic SO2s magnitude and variation in the UTLS region in general. We further compare the GOCART results with in-situ SO2 measurement from ground based network and various aircraft campaigns in the recent decades. Sparse SO2 measurements in the UTLS region show significant temporal and spatial variations. Model simulation with different emission inputs, spatial resolution, SO2 in-cloud vertical transport and chemistry parameterization all contribute to significant model variations.