A21B-0120
Interannual Variability and Trends of CH4, CO and OH using the Computationally-Efficient CH4-CO-OH (ECCOH) Module

Tuesday, 15 December 2015
Poster Hall (Moscone South)
Yasin F Elshorbany1,2, Bryan N Duncan1, Sarah Strode1,3, James S Wang3,4 and Jules Kouatchou1,5, (1)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (2)University of Maryland College Park, Earth System Science Interdisciplinary Center, College Park, MD, United States, (3)Universities Space Research Association Columbia, Columbia, MD, United States, (4)NASA Goddard Space Flight Ctr, Greenbelt, MD, United States, (5)Science Systems and Applications Inc, Lanham, MD, United States
Abstract:
The methane, carbon monoxide and hydroxyl radical (CH4-CO-OH) atmospheric system is nonlinear and determines the global tropospheric oxidizing capacity. In this study, we implemented the computationally Efficient CH4-CO-OH Module (ECCOH) into the NASA GEOS-5 Atmospheric Global Circulation Model (GEOS-5 AGCM). We investigated the key processes that affected the observed CH4, CO and OH trends and variability from 1988-2008. The simulated surface concentrations of methane and CO, using constant and variable emission scenarios, have been compared and contrasted with that from the in situ measurements. Simulated CH4 dry column is compared to that of the SCIAMACHY while the CO total column is compared to that of TES/MLS and MOPITT. We present our results of the sensitivity of methane, CO, and OH spatial and temporal distributions to the various causal factors that influence them, such as emissions, the overhead ozone column, lightning NO emissions, etc. We demonstrate the importance of using variable emissions and OH to drive the chemistry climate models given that recent modeling studies tend to use constant emissions of CO, and/or CH4 and and/or OH chemistry.