Chemical Mechanisms and Their Applications in the Goddard Earth Observing System (GEOS) Earth System Model

J. Eric Nielsen, Steven Pawson, Andrea Molod, Benjamin Auer, Arlindo M. da Silva, Anne R. Douglass, Bryan Duncan, Qing Liang, Michael Manyin, Luke D. Oman, William Putman, Susan E. Strahan (+1 others)
2017 Journal of Advances in Modeling Earth Systems  
Key Points: • The GEOS Earth System Model's architecture is based on ESMF and the GMAO's middleware layer called MAPL. • GEOS uses a common code base of interchangeable chemical components for data assimilation, forecasting, and research. • GEOS is applied to atmospheric chemistry topics ranging from diurnal air quality variations to climate change. Abstract NASA's Goddard Earth Observing System (GEOS) Earth System Model (ESM) is a modular, general circulation model (GCM) and data assimilation
more » ... ystem (DAS) that is used to simulate and study the coupled dynamics, physics, chemistry, and biology of our planet. GEOS is developed by the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center. It generates near-real-time analyzed data products, reanalyses, and weather and seasonal forecasts to support research targeted to understanding interactions among Earth-System processes. For chemistry, our efforts are focused on ozone and its influence on the state of the atmosphere and oceans, and on trace-gas data assimilation and global forecasting at mesoscale discretization. Several chemistry and aerosol modules are coupled to the GCM, which enables GEOS to address topics pertinent to NASA's Earth Science Mission. This manuscript describes the atmospheric chemistry components of GEOS and provides an overview of its Earth System Modeling Framework (ESMF)-based software infrastructure, which promotes a rich spectrum of feedbacks that influence circulation and climate, and impact human and ecosystem health. We detail how GEOS allows model users to select chemical mechanisms and emission scenarios at run time, establish the extent to which the aerosol and chemical components communicate, and decide whether either or both influence the radiative transfer calculations. A variety of resolutions facilitates research on spatial and temporal scales relevant to problems ranging from hourly changes in air quality to trace gas trends in a changing climate. Samples of recent GEOS chemistry applications are provided.
doi:10.1002/2017ms001011 pmid:29497478 pmcid:PMC5815385 fatcat:exbp4xms75fvjlgxoznoksgr5y