Metop-A ASCAT 25 km Winds

Discontinued Archived NRT product

The ASCAT Wind Product contains measurements of the wind direction and wind speed above the sea surface. The measurements are obtained through the processing of scatterometer data originating from the ASCAT instrument on EUMETSAT's Metop-A satellite, as described in the ASCAT Wind Product User Manual.

Acronym : ASCAT25
Product navigator reference :


OSI SAF producer : Royal Netherlands Meteorological Institute
Identifier : OSI-102
Digital object identifier (DOI) 10.15770/EUM_SAF_OSI_NRT_2020
Acronym for EDC (APNM) : OAS025
Processing level : L2
Satellite input : Metop-A/ASCAT
Other input : ECMWF outputs (wind, SST, land-sea mask)
Temporal sampling : Continuous
Timeliness : ? The timeliness is the time elapsing from the sensing time of the last contributing file to the product dissemination to users. It is similar to the latency. 2 h 45
Spatial coverage : Global
Spatial sampling : 25 km
File Formats : WIND FTP Server (BUFR), WIND FTP Server (NetCDF3), WMO Global Telecommunication System (BUFR), EDC (BUFR), EDC (NetCDF3), EUMETCast (BUFR)
Characteristics & methods : Swath sigma0’s and wind vectors
Data Access
Accuracy Requirements
Target accuracy : Better than 2 m/s in wind component Stdev with a bias of less than 0.5 m/s in wind speed on a monthly basis.
Verification/validation method : Triple collocation with NWP and buoys
Applications and users
Usage : * Operational Met Services (including assimilation in at least 8 NWP models, nowcasting)
* Operational analyses and ocean models
* Research or Environmental monitoring.
Last date :
  • This ASCAT Multi-parameter product contains surface wind vectors over ocean and soil moisture index over land. Additionally, the backscatter values involved in the retrieval of the geophysical parameters above are also included, as well as several quality flags to facilitate the use of the data. This product superseded EO:EUM:DAT:METOP:ASCAT25 (Only Metop-A - Acronym for EDC (APNM) : OASW025) on the 28/02/2011 which contains only backscatter and wind information.

    It is recommended that the reprocessed ASCAT winds data records (EO:EUM:DAT:METOP:OSI-150-B, EO:EUM:DAT:METOP:OSI-150-A)
    are used instead of this archived NRT product.
    See also OSI-102-b (Metop-B ASCAT 25 km Winds).
    Product upgraded on 2018-09-25: geophysical model function CMOD7 used instead of CMOD5, auxiliary data " stress-equivalent
    ECMWF winds " instead of "real 10m ECMWF background model winds"

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