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DATA

Discover and download the Earth observation data you need from the broad catalogue of missions the European Space Agency operate and support.

  • 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 approval (Restrained)

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    ERS-1/2 ATSR Gridded Brightness Temperature/Reflectance [AT1/AT2_TOA_1P]

    The Gridded Brightness Temperature/Reflectance (GBTR) product contains top of atmosphere (TOA) brightness temperature (BT) values for the infra-red channels and reflectance values for the visible channels. Values for each channel and for the nadir and forward views occupy separate measurement data sets. Additional MDS contain cloud and land/sea flags and confidence flags for each image pixel. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Gridded Surface Temperature [AT1/AT2_NR__2P]

    The Gridded Surface Temperature (GST) Product is the Level 2 full resolution geophysical product. The product contains gridded sea-surface temperature images using both nadir and dual view retrieval algorithms. The product includes pixel latitude/longitude positions, X/Y offset and the results of the cloud-clearing/land-flagging. It contains a single measurement data set the content of which is switchable, that is to say, the content of each pixel field will depend on the surface type. Specifically, the contents of the data fields will depend on the setting of the forward and nadir cloud flags and the land flag. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR ARC L2P/L3U [UPA-L2P_GHRSST/L3U_GHRSST]

    The L2P product contains full resolution dual-view Sea Surface Temperature (SST) values. These SST use the ARC SST retrieval and cloud screening which differ from the methods used to produce the Gridded Surface Temperature (ATS_NR__2P) products. In addition to SST, the L2P products contain the ATSR Saharan Dust Index (ASDI) and the clear-sky probability estimated by the ARC cloud detection algorithm. The L2P processor also generates L3U products; these are the L2P products averaged onto a regular grid at 0.1 degree resolution (they are therefore similar to the AR / Meteo Envisat-format products). The L2P and L3U products are provided in NetCDF-4 format following GHRSST Data Specifications (GDS) v2. The L2P/L3U archive has been reprocessed with a new processor based upon the ARC SST; the changes are outlined in full in the L2P Reprocessing User Note.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Averaged Surface Temperature [AT1/AT2_AR__2P]

    The Averaged Surface Temperature Product (AST) contains averaged geophysical data at two different resolutions, and with respect to two different averaging schemes: measurement data sets at resolutions of 0.5 by 0.5 degrees and 10 by 10 arcmin with respect to a latitude/longitude grid; other data sets contain data averaged over equal area cells of 50 by 50 km and 17 by 17 km aligned with the satellite ground track. Both top-of-atmosphere and surface data sets are provided. The surface temperature data sets provide, for sea cells, nadir and dual view sea surface temperatures, and for land cells, land surface temperature (currently 11 micron BT) and NDVI. Cloud data is also included. No ADS are included in the AST product; auxiliary data is contained within the MDS. The data sets of the AST product are arranged by surface type and resolution. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - External Data (Restrained)

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    ERS-1/2 ATSR ARC Level 3 products [AT1/AT2_AVG_3PAARC]

    The recommended ATSR Level 3 products for Sea Surface Temperature (SST) applications are the ARC (ATSR Re-processing for Climate) Level 3 products. ARC reprocesses the ATSR multi-mission archive using new cloud detection and SST retrievals to produce a homogenous record of sea surface temperature. The main ARC objective is to reduce regional biases in retrieved SST to less than 0.1 K for all global oceans while creating a very homogenous record with a stability (lack of drift in the observing system and analysis) of 0.05 K per decade. ARC products are available for ATSR-1, ATSR-2 and AATSR. ARC products are provided in netCDF format and contain data for both the skin SST and the SST estimated for depths of 0.2 and 1.0 m (corresponding approximately to drifter and moored buoy depths). The AATSR estimated depth SSTs are adjusted to a local equatorial crossing time of 10:30 (approximately half an hour after observation), to provide continuity with ATSR-1 and ATSR-2 data. The ARC project was led by Chris Merchant (University of Reading, formerly of the University of Edinburgh) and funded by NERC and the UK Government.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Meteo Product [AT1/AT2_MET_2P]

    The data is a fast delivery Meteo product designed for use by meteorological offices, and contains averaged BT and SST at 10 arc minute resolution. The single MDS comprises the fields of MDS#3 (SST record, 10 arc min cell) of the AST product, with the addition of Average Brightness Temperature (ABT) fields (BT/TOA sea record, 10 arc min cell) to make it more self-contained. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.