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  • Documents (262)
  • Document - Newsletter

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    Earth Online Newsletter - 09 February 2024

    This issue of the Earth Online Newsletter covers a selection of the latest news and events from ESA.

  • News - Thematic area articles

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    Transforming space data into climate action

    ESA’s Earth observation activities are playing a key role in the revitalised global drive to combat climate change.

  • News - Spotlight on EO community

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    Introducing Mirko Albani

    In this short introduction, ESA's Heritage Missions Programme Manager describes what he likes most about ESA's long term archive of satellite mission data and his role in the programme.

  • Activity - Projects

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    Dragon 2 Cooperation Programme

    The Dragon 2 Programme focussed on the exploitation of ESA, ESA's Third Party Missions and Chinese Earth observation data for science and applications development in land, ocean and atmospheric applications.

  • News - Data Release news

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    New reprocessing of datasets celebrates 30 years of ERS

    The ERS programme celebrated its 30th anniversary on 17 July. Today, we are still exploiting ERS data and experts continue to work on improving the altimeter, radiometer and SAR data the programme acquired.

  • News - Success Stories

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    ERS Heritage Data allow for 30 years of science

    At their time of launch thirty years ago, the two ERS satellites were the most sophisticated Earth observation spacecraft ever developed and launched by Europe.

  • Tools - Apps

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    Heritage Missions app for iOS

    Download the Heritage Missions application to discover what the missions were about, how it worked and what the elements of the space and ground segment that make these missions unique.

  • Tools - Apps

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    Heritage Missions app for Android

    Download the Heritage Missions application to discover what the missions were about, how it worked and what the elements of the space and ground segment that make these missions unique.

  • Data - Fast Registration with immediate access (Open)

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    ERS PRARE Precise Orbit Product (ERS.ORB.POD/ERS.ORB/PRC)

    The precise orbit results from a data reduction process in which all available tracking data (Single-Lens Reflex, radar altimeter crossovers, PRARE range and Doppler data) and most accurate correction, transformation and dynamical models are taken into account and in which high level numerical procedures are applied. These orbits are "optimal" achievable representations of the real orbital motion under the circumstances of tracking situation and the "state of the art" model situation. The precise orbit product for the ERS satellites are the satellite ephemeris (position and velocity vector) including time tag, given in a well-defined reference frame, together with the nominal satellite attitude information and a radial orbit correction. Several orbit solutions are currently distributed: A new set of ORB POD (Precise Orbit Determination - REAPER v2) computed with the most updated model standards for the complete ERS-1 and ERS-2 mission. A previous set of ORB POD (REAPER v1) data already available on the ESA dissemination site since 2014, covering the ERS-1 full mission and the ERS-2 mission up to July 2003. ORB PRC which is the original Precise Orbit dataset computed during the ERS mission operations for ERS-1 and ERS-2. In the new POD dataset (REAPER v2) for the ERS-1 and ERS-2 missions, two different orbit solutions are provided together with the combined solution to be used for processing of the radar altimeter measurements and the determination of geodetic/geophysical products: those computed by DEOS (Delft Institute of Earth Observation and Space Systems), and those generated by ESOC (European Space Operations Centre) using different software (GEODYN and NAPEOS respectively). Careful evaluation of the various solutions of REAPER v2 has shown that the DEOS solution for both ERS-1 and ERS-2 has the best performance and is recommended to be used as reference. See the ERS Orbit Validation Report. For the previous version of the POD data set (REAPER v1), with ERS-2 mission data only up to 2003, three different orbit solutions together with the combined solution are available. These precise orbits for ERS-1 and ERS-2 have been computed at DEOS, ESOC, and GFZ (Deutschen GeoForschungsZentrums) using different software and different altimeter databases. Combined solutions have been created using three individual solutions for each satellite. All orbits were derived using consistent models in the same LPOD2005 terrestrial reference frame. These new orbit solutions show notable improvement with respect to DGME04 orbits (Scharroo and Visser, 1998). Thus, RMS crossover differences of new orbits improved by 4-9 mm. Careful evaluation of the various solutions has shown that the combined solution for both ERS-1 and ERS-2 has the best performance. All POD orbit files (REAPER v1/v2) are available in SP3c format.

  • Data - Fast Registration with immediate access (Open)

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    ERS-2 SCATTEROMETER Surface Soil Moisture Time Series and Orbit product in High and Nominal Resolution [SSM.H/N.TS - SSM.H/N]

    Surface soil moisture records are derived from the backscatter coefficient measured by the Scatterometer on-board the European Remote Sensing satellite (ERS-2) using the Technische Universität (TU) Wien soil moisture retrieval algorithm called WARP (WAter Retrieval Package). In the WARP algorithm, the relative surface soil moisture estimates, given in degree of saturation Sd, range between 0% and 100% are derived by scaling the normalized backscatter between the lowest/highest backscatter values corresponding to the driest/wettest soil conditions. Surface Soil Moisture - Time Series product: The products generated are the surface soil moisture time series, where for each grid point defined in a DGG (Discrete Global Grid) is stored the time series of soil moisture and its noise, the surface state flag, the geolocation and the satellite parameters. The spatial resolution of the products is about 25 km x 25 km (high resolution) or 50 km x 50 km (nominal resolution) geo-referenced on the WARP grid. The location of the points can be viewed interactively with the tool DGG Point Locator. Surface Soil Moisture - Orbit product: In addition to WARP, a second software package, referred to as WARP orbit, was developed in response to the strong demand of soil moisture estimates in satellite orbit geometry. The Level 2 soil moisture orbit product contains a series of Level 1 data information, such as the backscatter, the incidence angle and the azimuth angle for each triplet together with the surface soil moisture and its noise, normalized backscatter at 40° incidence angle, parameters useful for soil moisture, the geolocation and the satellite parameters. The soil moisture orbit product is available in two spatial resolutions with different spatial sampling distances: Spatial sampling on a regular 12.5 km grid in orbit geometry with a spatial resolution of about 25 km x 25 km (High resolution) Spatial sampling on a regular 25 km grid in orbit geometry with a spatial resolution of about 50 km x 50 km (Nominal resolution). The spatial resolution is defined by the Hamming window function, which is used for re-sample of raw backscatter measurements to the orbit grid in the Level-1 ground processor. Please consult the Product Quality Readme file before using the ERS-2 Surface Soil Moisture data.

  • Mission - Heritage Missions

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    ERS

    The ERS programme was composed of two missions, ERS-1 and ERS-2, which together observed the Earth for 20 years, from 1991 to 2011.

  • News - Data Release news

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    Updated Precise Orbit data (POD) for the full ERS-1 and ERS-2 mission available

    The Precise Orbit files (ERS.ORB.POD) for the entire ERS-1 and ERS-2 mission periods have been reprocessed with up-to-date standards.

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 28 Apr 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 14 Apr 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 12 May 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 05 May 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 07 Apr 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 21 Apr 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 08 Jul 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report

  • Document - Quality Report

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    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report 21 Jul 2002

    ERS-2 AMI-SAR/AMI-Scatterometer Weekly Report