Minimize Dataset Details
Earth Topics (Applications)
  • Land
  • Topography/Mapping

  • Snow and Ice
  • Sea Ice

  • Ocean and Coast
  • Ocean Currents and Topography

  • Solid Earth
  • Geoid

  • Atmosphere
  • Winds

    Instrument type
  • RA
  • Mission
    Date of Launch:
    ERS-1 - 17 July 1991
    ERS-2 - 21 April 1995
    Mission Status:
    ERS-1 ended on March 2000 and ERS-2 September 2011 
    Orbit Height:
    782 to 785 km
    Orbit type:
    Near-circular, polar, Sun-synchronous
    Swath Width:
    5 km
    Radar Altimeter REAPER Geophysical Data Record - GDR
    (3578) recent views
    Last update: 10 September 2014

    This is a RA Geophysical Data Record (GDR) product containing radar range, orbital altitude, wind speed, wave height and water vapour from the ATSR/MWR as well as geophysical corrections.

    The REAPER (REprocessing of Altimeter Products for ERS) product is generated by applying a similar processing as for Envisat RA-2 on the Level 1b consolidated waveforms using 4 different re-trackers, RA calibration improvement, new precise orbit solution (POD), new ionospheric corrections (NICO09 until 1998 and GIM up to 2003), ECMWF ERA-interim model and updated SSB tables.

    This product contains two data rates: a low rate of 1Hz and a high rate of 20Hz.

    Most 1Hz data is also represented at 20Hz, while microwave radiometer (ATSR/MWR) data and the atmospheric and geophysical corrections are only given at 1 Hz.

    The REAPER GDR (ERS_ALT_2_) is a global product including data over ocean, ice and land.

    It should be noted that this product differs from the Envisat RA2 in the following ways:

    • the product format; which is NetCDF (more details can be found in the Product Handbook), and not PDS
    • the product is delivered based on orbit acquisition and not per pass (pole-to-pole)
    Data Set Specifications
    Spatial coverage: 90 N, 90 S, 180 W, 180 E
    Processing level
    Level 2
    How to access this data

    Data is distributed via FTP upon registration.

    REAPER ERS-1 data is available from 3 August 1991 to 2 June 1996

    REAPER ERS-2 data is available from 15 May 1995 to 4 July 2003

    This product is extended through Envisat RA-2 data

    See also related news of 11 September 2014.

    Terms & Conditions applicable
    Utilisation of this data is subject to ESA's Earth Observation Terms and Conditions


    REAPER Data Product Handbook


    REAPER Calibration Monitoring


    Cal/Val evaluation of REAPER ERS altimeter data


    RA L2 Validation Report


    REAPER Data Performance Monitoring and QA


    More RA Documents