Seminar: NASA's High-Resolution GEOS Forecasting and Reanalysis Products: A unified Tool from Local to Global Scales

Abstract

NASA's Global Modeling and Assimilation Office (GMAO) produces high-resolution global forecasts for weather, aerosols, and air quality. The NASA Global Earth Observing System (GEOS) model has been expanded to provide global near-real-time 5-day forecasts of atmospheric composition at unprecedented horizontal resolution of 0.25 degrees (~25 km). This composition forecast system (GEOS-CF) combines the operational GEOS weather forecasting model with the GEOS-Chem chemistry module to provide detailed analysis of a wide range of air pollutants such as ozone, carbon monoxide, nitrogen oxides, and fine particulate matter (PM2.5). Satellite observations are assimilated into the system for improved representation of weather and smoke, and now ozone, nitrogen dioxide and sulfur dioxide using the GEOS Constituent Data Assimilation System (CoDAS) to improve atmospheric composition modeling. While the main focus of this new product is on tropospheric air quality information, the GEOS-Chem chemistry model used in this system includes the unified tropospheric stratospheric chemistry mechanism for improved stratospheric ozone forecasts. Additionally, machine learning techniques can be used to correct for sub-grid-scale variability and potentially speed up chemistry for applications such as ensemble data assimilation. GEOS-CF is used to support many NASA missions, including the as the prior for the TEMPO satellite trace gas retrievals and forecasts for field campaigns. Future work includes a composition reanalysis for the 21st century.