The Description and Validation of a Computationally-Efficient CH4-CO-OH (ECCOHv1.01) Chemistry Module for 3D Model Applications

• Published in: Publications of the Astronomical Society of Japan Vol. 9; no. 2 Witer
• Main Authors: Elshorbany, Yasin F., Duncan, Bryan N., Strode, Sarah A., Wang, James S., Kouatchou, Jules
• Format: Journal Article
• Language: English
• Published: Goddard Space Flight Center Geoscientific Model Development 01.01.2016
• Subjects: Geosciences (General); Chemistry Model; Earth System Model; Carbon Cycle Model
• ISSN: 0004-6264; 2053-051X

We present the Efficient CH4-CO-OH (ECCOH) chemistry module that allows for the simulation of the methane, carbon monoxide, and hydroxyl radical (CH4-CO- OH) system, within a chemistry climate model, carbon cycle model, or Earth system model. The computational efficiency of the module allows many multi-decadal sensitivity simulations of the CH4-CO-OH system, which primarily determines the global atmospheric oxidizing capacity. This capability is important for capturing the nonlinear feedbacks of the CH4-CO-OH system and understanding the perturbations to methane, CO, and OH, and the concomitant impacts on climate. We implemented the ECCOH chemistry module in the NASA GEOS-5 atmospheric global circulation model (AGCM), performed multiple sensitivity simulations of the CH4-CO-OH system over 2 decades, and evaluated the model output with surface and satellite data sets of methane and CO. The favorable comparison of output from the ECCOH chemistry module (as configured in the GEOS- 5 AGCM) with observations demonstrates the fidelity of the module for use in scientific research.