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         MISSION / VISION    |    About EMC

NOAA Environmental Modeling System

For the past several years, a common modeling framework called the NOAA Environmental Modeling System (NEMS) has been in development to streamline the interaction of analysis, forecast, and post-processing systems within NCEP. The NEMS architecture is based on the Earth System Modeling Framework (ESMF). This marks the first general use of ESMF within NCEP.

NEMS is a shared, portable, high performance software superstructure and infrastructure for use in operational prediction models at the National Centers for Environmental Prediction (NCEP). It is also part of the National Unified Operational Predication Capability (NUOPC) with Navy and the Air Force, and will eventually provide support to the community through the Developmental Test Center (DTC). Currently, the Global Forecast System (GFS), the Global Ensemble Forecast System (GEFS), the B-grid version of the Nonhydrostatic Multiscale Model (NMM-B), and the Flow-following finite-volume Icosahedral Model (FIM) are placed together within NEMS.

As NEMS evolves and grows, this website will become more robust and detailed. Thank you for your continued patience with our development!

Current Operational Implementations

NMM-B with nests:
    Fixed domain nests run to 60 hr:
    • 3 km CONUS
    • 3 km Alaska
    • 3 km HI & PR
    Single locatable 1.5 km (CONUS or Alaska) nest to 36 hr
NEMS GFS Aerosol Component (NGAC)

Operational Implementation Plans

Grib2 output

NEMS Delivery Plans

Past Deliveries:
Multimodel ensemble
GRIB2 output
Moving nests
Two-way nests
2012+ Deliveries:
NMM-B nested in GFS
Coupled ocean atmosphere
HYCOM ocean
netCDF output
Postprocessor in WRITE


The NOAA Environmental Modeling System at NCEP - Mark Iredell and Tom Black - AMS Conference on NWP - January 27, 2011

Links of Interest

To view operational T126 L64 NRT dust forecasts from NEMS GFS aerosol component (NGAC) click here. 3-hr AOD and surface mass concentrations for the globe and several regional areas (trans-Altantic, CONUS, Pacific, Asia) are posted

NEMS / NMMB HOWTO - Version 2 (evolving)

Navigational Links

The following links will navigate you to other pages of the NEMS website and are identical to the tabs at the top of the page.

Getting Started
Running NEMS

Points of Contact

Documentation, experiments, web content: Mark Iredell
Others listed under the 'Miscellany' tab above.