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Full catalog/UFS GEFSV13REPLAY PDS
UFS GEFSV13REPLAY PDS·dataset

Retrospective archive for next GEFS forecast model (NOAA)

NOAA Unified Forecast System (UFS) Global Ensemble Forecast System (GEFS) Version 13 Replay
atmosphere NOAA NOAA active
In plain English

What it measures. A global archive of atmospheric and ocean variables, including temperature, humidity, winds, saltiness, and currents, at quarter-degree resolution worldwide.

How it's made. NOAA generated it by replaying its coupled forecast model against existing reanalyses (ERA5 for the atmosphere, ORAS5 for the ocean and ice) to lock in known conditions.

How & where you'd use it. It supports development and testing of the next versions of NOAA's global ensemble and weather forecast models; a technical input for modelers.

What's measured

aws-pdsagricultureclimatemeteorologicalweather

Coverage & cadence

  • Time span— → ongoing

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The NOAA Unified Forecast System (UFS) / Global Ensemble Forecast System version 13 (GEFSv13) Replay dataset supports the retrospective forecast archive in preparation for GEFSv13 / GFSv17. It includes a range of atmospheric and oceanic variables—such as temperature, humidity, winds, salinity, and currents—covering global conditions at a nominal horizontal resolution of ¼ degree, enabling detailed weather analysis. The dataset was generated by replaying the coupled UFS model against pre-existing external reanalyses; ERA5 for atmospheric data and ORAS5 for ocean and ice dynamics. Each simulation stream was initialized from these reanalyses, which were pre-processed for the UFS model components, including the GFDL Finite-Volume Cubed-Sphere Dynamical Core (FV3; 25 km, 127 vertical levels) and the Modular Ocean Model (MOM6; ¼ degree tri-polar grid, 72 vertical levels). This replay methodology enforces a predetermined model state while allowing cross-component fluxes and unconstrained processes to be computed. For the land surface, NOAA’s JEDI-based land data assimilation system incorporated snow depth observations from the NCEI Global Historical Climatology Network (GHCN) and satellite-derived snow cover from the U.S. National Ice Center. The JEDI Sea-ice Ocean and Coupled Analysis system (SOCA) adjusted sea-ice thickness and concentration for consistency with ORAS5. The original dataset spanned January 1994 to October 2023, with plans for ongoing updates and a 1-degree version covering 1958 to 2023. The dataset is hosted on AWS and GCP cloud services, courtesy of the NOAA Ope

Get the data

noaa_access.py
# NOAA Open Data on AWS — public S3, no login
import s3fs

fs = s3fs.S3FileSystem(anon=True)
# find this dataset's bucket in the docs link in the sidebar, then:
# files = fs.ls("noaa-<bucket>/...")
# open NetCDF/GRIB with xarray, COGs with rioxarray
NOAA Open Data is on public AWS S3 — no login at all (anonymous access).