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.
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SMAP Radiance Assimilation Over Land Improves Analysis and Prediction of Tropical Cyclone Idai

SMAP Radiance Assimilation Over Land Improves Analysis and Prediction of Tropical Cyclone Idai

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GMAO Campaign Support Highlights Versatility and Range of Product Capabilities

GMAO Campaign Support Highlights Versatility and Range of Product Capabilities

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SAGE III/ISS Data Assimilation System Effective In Reducing Stratospheric Observational Data Gaps

SAGE III/ISS Data Assimilation System Effective In Reducing Stratospheric Observational Data Gaps

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The Stratospheric Sudden Warming of March 2025 Abruptly Ended the NH Stratospheric Polar Vortex

The Stratospheric Sudden Warming of March 2025 Abruptly Ended the NH Stratospheric Polar Vortex

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GEOS-FP Excels At Predicting Presidents' Week Mid-Atlantic Snowfall

GEOS-FP Excels At Predicting Presidents' Week Mid-Atlantic Snowfall

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FLUID Imagery and Data Access

Weather Analyses and Forecasts

GMAO Mission Support

Composition Forecast Products

GMAO Reanalysis Products

GMAO Carbon Reanalysis

GMAO News

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

11.14.2024

New Paper Reveals Drop in Levels of Global Freshwater with Co-Author Mike Bosilovich(11.15.24)

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) patch May 22, 2024 - (May 22, 2024)
GEOS Forward Processing (GEOS-FP) Upgrade Feb 7, 2023 - (January 25, 2023)
GEOS FP Upgraded to GEOS-5.29.4 on March 1 - (March 21, 2022)

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Page Last Updated: 11/13/2025