Global Modeling and Assimilation Office

Global Modeling and Assimilation Office
Name	Global Modeling and Assimilation Office
Type	Research office
Established	1995
Headquarters	Greenbelt, Maryland
Parent organization	National Aeronautics and Space Administration (NASA)

Contents

Global Modeling and Assimilation Office The Global Modeling and Assimilation Office provides centralized NASA science leadership for global atmospheric modeling and data assimilation, integrating observations from Terra (satellite), Aqua (satellite), Suomi NPP and missions such as Aqua, Aura and ICESat. It develops coupled global models used by programs linked to NOAA, European Space Agency, Japan Aerospace Exploration Agency, UK Met Office and research centers like Goddard Space Flight Center, Jet Propulsion Laboratory and Columbia University. The office supports interagency initiatives including United States Global Change Research Program, World Meteorological Organization activities and collaborations with National Center for Atmospheric Research and Scripps Institution of Oceanography.

Overview

The office was founded amid 1990s efforts to unify satellite assimilation strategies championed by leaders from Goddard Space Flight Center, NOAA, European Space Agency and academic groups at Harvard University and Pennsylvania State University. Early programs integrated instrument datasets from Landsat, ERS-2, TOPEX/Poseidon and TRMM, driving partnerships with Jet Propulsion Laboratory and California Institute of Technology. Subsequent development phases incorporated contributions from research teams at NASA Ames Research Center, Brookhaven National Laboratory and Los Alamos National Laboratory, and responded to community initiatives such as Global Climate Observing System and the GEWEX program.

The office contributes modeling and assimilation expertise to flight missions including Aura (satellite), Suomi NPP, OCO-2, CALIPSO and ICESat-2, and to field campaigns like SEAC^4RS, ARCTAS and DISCOVER-AQ. It supports sustained programs such as MERRA reanalysis, GMAO-linked operational runs for NCEP and collaborations on initiatives with European Centre for Medium-Range Weather Forecasts, Copernicus Programme teams and World Climate Research Programme panels. The office also engages with projects at NASA Jet Propulsion Laboratory, NASA Langley Research Center and international consortia including GEOS-Chem and SPARC.

Key systems developed include coupled frameworks used for atmospheric chemistry, radiation and dynamics employed by MERRA-2 and successor systems, integrating modules from GFDL, NCAR Community Earth System Model, WRF and components used at UK Met Office and ECMWF. Tools for model evaluation and visualization are shared with PANGAEA (data repository), NCAR Command Language, Panoply and community libraries managed by NASA Earth Exchange and Open Science Grid. The office maintains software ecosystems compatible with languages and platforms used at Massachusetts Institute of Technology, Stanford University and Princeton University research groups.

The office advances assimilation methods including ensemble Kalman filter variants, four-dimensional variational assimilation and hybrid ensemble–variational approaches that mirror techniques adopted by ECMWF, NCEP, UK Met Office and European Centre for Medium-Range Weather Forecasts. Observing system experiments integrate data from instruments aboard MODIS, OMI, MISR, GRACE and AIRS as well as in situ networks operated by Global Ocean Observing System, Argo floats and Global Atmosphere Watch. Methodological development draws on research from University Corporation for Atmospheric Research, Scripps Institution of Oceanography and Princeton University.

Partnerships span international agencies such as European Space Agency, Japan Aerospace Exploration Agency and Canadian Space Agency as well as domestic agencies including NOAA, Department of Energy laboratories and academic partners like Massachusetts Institute of Technology, Columbia University and University of Washington. The office participates in working groups with World Meteorological Organization, Intergovernmental Panel on Climate Change authors, and consortia such as GEOSS and Working Group on Numerical Experimentation. It also coordinates with applied programs at US Army Corps of Engineers, Federal Aviation Administration research offices and regional climate centers.

Outputs support climate assessment reports produced by Intergovernmental Panel on Climate Change, inform air quality policy discussions at United Nations Environment Programme and aid disaster response coordinated with Federal Emergency Management Agency and National Weather Service. Reanalysis datasets and model products underpin research at institutions including Harvard University, Massachusetts Institute of Technology, Princeton University and University of California, Berkeley, and are used in sectoral applications by NASA Applied Sciences Program, NOAA National Marine Fisheries Service and international partners such as European Commission agencies.