• Home
  • What is OAFlux
  • Data Products
  • Data Access
  • Documents
  • Research
  • Publications
  • Contact us
  • Links

  • whoilogo



    Webpage designed by
    Location: about OAFlux

    Heat flux freshwater (evaporation) momentum
    What is the OAFlux project?

    The OAFlux project aims to provide consistent, multi-decade, global analysis of air-sea heat, freshwater (evaporation), and momentum fluxes for use in studies of global energy budget, water cycle, atmosphere and ocean circulation, and climate.


    The OAFlux project applies objective analysis approach to take into account data errors in the development of enhanced global flux fields. The objective analysis denotes the process of synthesizing measurements/estimates from various sources. Such process reduces error in each input data source and produces an estimate that has the minimum error variance.

      Notable features of OAFlux products

    The OAFlux products are determined from using the best-possible estimates of flux-related surface meteorology and the state-of-the-art bulk flux parameterizations (Yu et a. 2008, make a link to the online technical report).

    - The best possible estimates for flux-related surface meteorological variables are obtained by applying an
    advanced objective analysis that seeks optimal synthesis of satellite and NWP data sources (Note that
    the present satellite observing capacity cannot provide direct measurements of near-surface air and
    humidity, and hence auxiliary datasets have to be supplied to fill the missing data sets).

    - The latent and sensible heat flux estimates are computed from the objectively analyzed surface
    meteorological variables by using the COARE bulk flux algorithm 3.0 (Fairall et al. 2003).

      Availability of OAFlux products

    The project currently provides global time series of ocean latent and sensible heat fluxes, ocean evaporation, and flux-related surface meteorology from 1958 to present, and maintains a twice-per-year update of the datasets.

    Global analysis of satellite-based high-resolution ocean surface vector wind fields has also been developed for the period from July 1987 onward and will be released soon.

    All data sets are freely available from the project ftp site.

      Use of OAFlux products

    OAFlux products can be combined with existing surface radiation products from ISCCP to obtain net heat flux (see image below) over the global oceans, and with existing precipitation products from GPCP to obtain freshwater (E-minus-P) flux (see image below). These, together with OAFlux vector wind analysis (see image below), provide complete datasets of air-sea heat, freshwater, and momentum fluxes.

    Please acknowledge the global ocean heat flux and evaporation products were provided by the WHOI OAFlux project ( funded by the NOAA Climate Observations and Monitoring (COM) program. For questions, please contact us.