GMAO - Global Modeling and Assimilation Office Research Site

Earth Sciences Division Sciences and Exploration

Reanalysis Long-term, model-based analyses of multiple datasets using a fixed assimilation system are a major focus in the GMAO. Building on the success of the atmospheric reanalyses conducted with GEOS, current research and development activities are directed at producing a major Earth System Reanalysis, including atmosphere, land, ocean, and ice.
Weather Analysis & Prediction To support NASA's satellite missions and field experiments, GMAO generates near-real-time atmospheric products using GEOS and distributes them to a broad community of users.
Seasonal-Decadal Analysis & Prediction GMAO uses coupled Earth-System models and analyses, along with a broad range of satellite observations, to study and predict phenomena that evolve on seasonal to decadal timescales.
Global Mesoscale Modeling Current computing capacity enables GMAO to simulate the entire globe at spatial resolutions previously only possible with regional models. These “global mesoscale model” simulations serve for forefront evaluations of model performance and form the basis for Observing System Simulation Experiments.
Observing System Science GMAO's mission to provide modeling support for NASA's satellite observations encompasses the need to examine the impacts of different observation types in weather and climate prediction. It also requires the ability to simulate potential new observation types, in order to assess their cost benefit, based on their likely impacts on prediction.
Explore

NASA's GEOS Model Captures Northeast Blizzard Structure Days in Advance

NASA's GEOS Model Captures Northeast Blizzard Structure Days in Advance

Splitting Anthropogenic and Biomass Burning Sources of Organic Carbon in GOCART-2G

Splitting Anthropogenic and Biomass Burning Sources of Organic Carbon in GOCART-2G

GMAO's GEOS Model Performs Well With Back-to-Back Winter Storms

GMAO's GEOS Model Performs Well With Back-to-Back Winter Storms

2025 Compound Weather Extremes in the Middle East

2025 Compound Weather Extremes in the Middle East

Extreme Winds in Argentina Lead to Significant November Dust Event

Extreme Winds in Argentina Lead to Significant November Dust Event

FLUID Imagery and Data Access

Weather Analyses and Forecasts

GMAO Mission Support

Composition Forecast Products

GMAO Reanalysis Products

GMAO Carbon Reanalysis

GMAO News

05.21.2026

GMAO Announces the Release of GEOS-S2S-3

06.17.2025

Fei Liu's ROSES-24 Proposal Accepted for Work on Improved NOx Modeling

03.28.2025

GMAO's Annika Jersild Featured In GSFC Early Career Scientist Spotlight

02.05.2025

2024 GMAO Peer Awards Honor Recipients' Outstanding Achievements

Forecasting Support

GEOS FP Weather Analyses & Forecasts ☁ ☀
Requests for Support
Supported NASA Orbital and Ground-Based Missions

Past Missions Supported

GEOS System News

GEOS Forward Processing (GEOS-FP) upgrade on February 26, 2026 - (February 06, 2026)
GEOS Forward Processing (GEOS-FP) patch May 22, 2024 - (May 22, 2024)
GEOS Forward Processing (GEOS-FP) Upgrade Feb 7, 2023 - (January 25, 2023)

GEOS System News

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Page Last Updated: 05/31/2026