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Surface Flux Analysis (SURFA)

A near-real-time quality monitoring system utilizing the SURFA datasets

A near-real-time quality monitoring system utilizing the SURFA datasets is available at

The ​Surface Flux Analysis (SURFA) project is a World Climate Research Programme (WCRP) initiative promoted by the WCRP's Working Groups on Surface Fluxes and Numerical Experimentation, Observation and Assimilation Panel, and Ocean Observation Panel for Climate.

The driver is the recognition by both the modeling and observation communities that accurate surface processes are important in improving Numerical Weather Prediction (NWP) and climate forecast skills. The SURFA objective is to institutionalize a facility for the evaluation of surface fluxes and related parameters from NWP and climate models, and the facility is equally useful for the evaluation of satellite-based fluxes and related parameters.

SURFA datasets fall into two categories: model simulations (NWP and climate model output) and observational data (from in situ and satellite platforms). In situ data provide ground-truth values for validations and evaluations of model simulations and satellite retrieved values.

Currently, NCEI has NWP model output from the ​European Centre for Medium-Range Weather Forecasts (ECMWF) and Germany's National Meteorological Service, the Deutscher Wetterdienst (DWD). The in situ data are from the OceanSITES reference stations.

The SURFA model data are on a global 0.25° x 0.25° grid. SURFA variables include major surface parameters such as temperature, wind, and radiation fluxes.


  • ECMWF NWP Output
    The ECMWF NWP SURFA fields are available, beginning in July 2007, through FTP or TDS/THREDDS.
  • German DWD NWP Output
    The German DWD NWP SURFA fields are available, beginning in January 2008, through FTP or TDS/THREDDS.
  • OceanSITES
    OceanSITES is a worldwide system of long-term, deepwater reference stations measuring dozens of variables and monitoring the full depth of the ocean from the air and sea interface down to 5,000 meters. See the OceanSITES website for more details. Access these data through FTP by selecting file names that start with "os_".

Dataset Documentation

  • SURFA Variables and Constants
    Download the SURFA Variables and Constants document for a complete list of all dataset variables. This document was prepared by Detlev Majewski, the WCRP Working Group on Numerical Experimentation representative, in consultation with the WCRP Working Group on Surface Fluxes Chair, Chris Fairall.
  • SURFA Submission Agreements
    The draft SURFA Submission Agreements provide guidelines between the data providers, such as ECMWF and DWD, and NCEI's archive.


Huai-Min Zhang, PhD
151 Patton Ave
Asheville, NC 28801
Phone: 1-828-271-4090
Fax: 1-828-271-4328

Ge Peng, PhD
Research Scholar
Cooperative Institute for Climate and Satellites–North Carolina
North Carolina State University
151 Patton Ave
Asheville, NC 28801
Phone: 1-828-257-3009
Fax: 1-828-257-3002