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

Area of Science:

• Earth System Science
• Atmospheric Chemistry
• Climate Modeling

Background:

• NASA's Goddard Earth Observing System (GEOS) is a modular Earth System Model (ESM) and Data Assimilation System (DAS).
• Developed by the Global Modeling and Assimilation Office (GMAO), it simulates coupled Earth system dynamics, physics, chemistry, and biology.
• GEOS provides near-real-time data products, reanalyses, and forecasts supporting Earth science research.

Purpose of the Study:

• To describe the atmospheric chemistry components of the GEOS model.
• To provide an overview of its Earth System Modeling Framework (ESMF)-based software infrastructure.
• To highlight GEOS's capability in simulating feedbacks influencing circulation, climate, and health.

Main Methods:

• Coupling of several chemistry and aerosol modules to the General Circulation Model (GCM).
• Utilizing an ESMF-based software infrastructure for modularity and flexibility.
• Enabling user selection of chemical mechanisms and emission scenarios at run time.

Main Results:

• GEOS facilitates research on ozone's influence on atmosphere and oceans.
• Trace gas data assimilation and global forecasting at mesoscale discretization are supported.
• The model allows detailed configuration of aerosol-chemistry interactions and their radiative effects.

Conclusions:

• GEOS enables comprehensive study of Earth system processes, from air quality to climate change.
• Its flexible infrastructure supports diverse research questions relevant to NASA's Earth Science Mission.
• The model's applications demonstrate its utility in understanding complex atmospheric interactions and impacts.