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Updated: Sep 4, 2025
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
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NASA GEOS Composition Forecast Modeling System GEOS-CF v1.0: Stratospheric Composition
K E Knowland1,2,3, C A Keller1,2,3, P A Wales1,2,3
1Universities Space Research Association (USRA)/GESTAR Columbia MD USA.
Journal of Advances in Modeling Earth Systems
|July 22, 2022
Summary
NASA
Area of Science:
- Atmospheric Science
- Earth System Modeling
- Climate Science
Background:
- NASA's Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) offers near-real-time atmospheric composition estimates and forecasts.
- The GEOS Earth system model is integrated with GEOS-Chem's unified chemistry extension (UCX) for comprehensive surface-to-stratosphere composition modeling.
Purpose of the Study:
- Describe the GEOS-CF system and its updates for stratospheric chemistry.
- Evaluate GEOS-CF's performance against observations for stratospheric composition.
- Highlight GEOS-CF's utility as a tool for atmospheric research.
Main Methods:
- Coupling the GEOS Earth system model with the GEOS-Chem UCX mechanism.
- Implementing updates to the GEOS-Chem UCX for improved stratospheric chemistry representation.
- Comparing GEOS-CF outputs with balloon, lidar, and satellite observations.
Main Results:
- GEOS-CF stratospheric ozone aligns well with assimilated data and observations.
- GEOS-CF forecasts demonstrated greater accuracy than GEOS FP during extreme events (e.g., 2020 polar vortexes).
- Spatial patterns of GEOS-CF stratospheric composition generally match satellite observations, despite identified biases.
Conclusions:
- GEOS-CF provides a valuable new resource for near-real-time atmospheric composition data.
- The integrated GEOS-Chem UCX chemistry enhances the model's ability to simulate stratospheric processes.
- Future work should address identified biases in nitrogen and chlorine species for improved accuracy.
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