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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 - EO Sign In Authentication (Open)

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    Fundamental Data Records for Radiometry [MWR_FDR___]

    This dataset is a Fundamental Data Record (FDR) resulting from the ESA FDR4ALT project. The Fundamental Data Record for Radiometry V1 products contain intercalibrated Top of the Atmosphere brightness temperatures at 23.8 and 36.5 GHz. The collection covers data for the ERS-1, ERS-2 and Envisat missions, and is built upon a new processing of Level 0 data, incorporating numerous improvements in terms of algorithms, flagging procedures, and corrections. Compared to existing datasets, the Radiometry FDR demonstrates notable improvements in several aspects: New solutions for instrumental effects (ERS Reflector loss, Skyhorn, and Sidelobe corrections) Native sampling rate of 7Hz with enhanced coverage The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Fundamental Data Records for Altimetry [ALT_FDR___]

    This dataset is a Fundamental Data Record (FDR) resulting from the ESA FDR4ALT project. The Fundamental Data Record for Altimetry V1 products contain Level 0 and Level 1 altimeter-related parameters including calibrated radar waveforms and supplementary instrumental parameters describing the altimeter operating status and configuration through the satellite lifetime. The data record consists of data for the ERS-1, ERS-2 and Envisat missions for the period ranging from 1991 to 2012, and bases on the Level 1 data obtained from previous ERS REAPER and ENVISAT V3.0 reprocessing efforts incorporating new algorithms, flags, and corrections to enhance the accuracy and reliability of the data. For many aspects, the Altimetry FDR product has improved compared to the existing individual mission datasets: New neural-network waveform classification, surface type classification, distance to shoreline and surface flag based on GSHHG Instrumental calibration information directly available in the product Improved Orbit solutions Correction of REAPER drawbacks (i.e., time jumps and negative waveforms) The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Sea Ice Thematic Data Product [ALT_TDP_SI]

    This is the Sea Ice Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing the sea ice related geophysical parameters, along with associated uncertainties: snow depth, radar and sea-ice freeboard, sea ice thickness and concentration. The collection covers data for the ERS-1, ERS-2 and Envisat missions, and bases on Level 1 data coming from previous reprocessing (ERS REAPER and the Envisat V3.0) but taking into account the improvements made at Level 0/Level 1 in the frame of FDR4ALT (ALT FDR). The Sea Ice TDP provides data from the northern or southern hemisphere in two files corresponding to the Arctic and Antarctic regions respectively for the winter periods only, i.e., October to June for the Arctic, and May to November for the Antarctic. For many aspects, the Sea Ice TDP is very innovative: First time series of sea-ice thickness estimates for ERS Homogeneous calibration, allowing the first Arctic radar freeboard time series from ERS-1 (1991) to CryoSat-2 (2021) Uncertainties estimated along-track with a bottom-up approach based on dominant sources ERS pulse blurring error corrected using literature procedure [Peacock, 2004] The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Land Ice Thematic Data Product [ALT_TDP_LI]

    This is the Land Ice Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing estimates of ice sheet surface elevation and associated uncertainties. The collection covers data for three different missions: ERS-1, ERS-2 and Envisat, and based on Level 1 data coming from previous reprocessing (ERS REAPER and the Envisat V3.0) but taking into account the improvements made at Level 0/Level 1 in the frame of FDR4ALT (ALT FDR). The Land Ice TDP focuses specifically on the ice sheets of Greenland and Antarctica, providing these data in different files. For many aspects, the Land Ice Level 2 and Level 2+ processing is very innovative: Improved relocation approach correcting for topographic effects within the beam footprint to identify the Point of Closest Approach Homogeneous timeseries of surface elevation measurements at regular along-track reference nodes. The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Inland Waters Thematic Data Product [ALT_TDP_IW]

    This is the Inland Waters Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing improved Water Surface Height (WSH) data record from the ERS-1, ERS-2 and Envisat missions estimated using the ICE1 retracking range for its better performance on the hydro targets. The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Ocean and Coastal Topography Thematic Data Product [ALT_TDP_OC]

    This is the Ocean and Coastal Topography Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing improved sea surface height anomaly data records both at 1 Hz and 20 Hz resolution to address climate and/or coastal areas studies. The collection covers data for the ERS-1, ERS-2 and Envisat missions. Note that a dedicated processing to coastal zones has been applied for coastal distances below 200 km. Compared to existing datasets, the Ocean and Coastal Topography TDP demonstrates notable improvements in several aspects: Up-to-date orbit and geophysical corrections applied Adaptive retracker for Envisat The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Ocean Waves Thematic Data Product [ALT_TDP_WA]

    This is the Ocean Waves Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing Significant Wave Height estimates for the ERS-1, ERS-2 and Envisat missions. Compared to existing datasets, the Ocean Waves TDP demonstrates notable improvements in several aspects: Great improvements for Envisat due to noise reduction from Adaptive retracker and High-Frequency Adjustment (HFA) All variables are given at 5 Hz The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - EO Sign In Authentication (Open)

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    Atmospheric Thematic Data Product [MWR_TDPATM]

    This is the Atmospheric Thematic Data Product (TDP) V1 resulting from the ESA FDR4ALT project and containing Total Column Water Vapour (TCWV), Cloud Liquid Water Path (LWP), Atmospheric Attenuation of the altimeter backscattering coefficient at Ku-band (AttKu), and Wet Tropospheric Correction (WTC), retrieved from observations of the Microwave Radiometer (MWR) instruments flown on-board the ERS-1, and ERS-2, and Envisat satellites. Compared to existing datasets, the Atmospheric TDP demonstrates notable improvements in several aspects: Improved temporal coverage, especially for ERS-2 Improved L0 -> 1 processing Two different corrections are provided based on a neural network retrieval or on a 1D-VAR approach The FDR4ALT products are available in NetCDF format. Free standard tools for reading NetCDF data can be used. Information for expert altimetry users is also available in a dedicated NetCDF group within the products. Please consult the FDR4ALT Product User Guide before using the data. The FDR4ALT datasets represent the new reference data for the ERS/Envisat altimetry missions, superseding any previous mission data. Users are strongly encouraged to make use of these datasets for optimal results.

  • Data - Fast Registration with approval (Restrained)

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    WorldView ESA archive

    The WorldView ESA archive is composed of products acquired by WorldView-1, -2, -3 and -4 satellites and requested by ESA supported projects over their areas of interest around the world Panchromatic, 4-Bands, 8-Bands and SWIR products are part of the offer, with the resolution at Nadir depicted in the table. Band Combination Mission GSD Resolution at Nadir GSD Resolution (20° off nadir) Panchromatic WV-1 50 cm 55 cm WV-2 46 cm 52 cm WV-3 31 cm 34 cm WV-4 31 cm 34 cm 4-Bands WV-2 1.84 m 2.4 m WV-3 1.24 m 1.38 m WV-4 1.24 m 1.38 m 8-Bands WV-2 1.84 m 2.4 m WV-3 1.24 m 1.38 m SWIR WV-3 3.70 m 4.10 m The 4-Bands includes various options such as Multispectral (separate channel for Blue, Green, Red, NIR1), Pan-sharpened (Blue, Green, Red, NIR1), Bundle (separate bands for PAN, Blue, Green, Red, NIR1), Natural Colour (pan-sharpened Blue, Green, Red), Coloured Infrared (pan-sharpened Green, Red, NIR). The 8-Bands being an option from Multispectral (COASTAL, Blue, Green, Yellow, Red, Red EDGE, NIR1, NIR2) and Bundle (PAN, COASTAL, Blue, Green, Yellow, Red, Red EDGE, NIR1, NIR2). The processing levels are: Standard (2A): normalised for topographic relief View Ready Standard: ready for orthorectification (RPB files embedded) View Ready Stereo: collected in-track for stereo viewing and manipulation (not available for SWIR) Map Scale (Ortho) 1:12,000 Orthorectified: additional processing unnecessary Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service. The following table summarises the offered product types EO-SIP Product Type Band Combination Processing Level Missions WV6_PAN_2A Panchromatic (PAN) Standard/View Ready Standard WorldView-1 and 4 WV6_PAN_OR Panchromatic (PAN) View Ready Stereo WorldView-1 and 4 WV6_PAN_MP Panchromatic (PAN) Map Scale Ortho WorldView-1 and 4 WV1_PAN__2A Panchromatic (PAN) Standard/View Ready Standard WorldView-2 and 3 WV1_PAN__OR Panchromatic (PAN) View Ready Stereo WorldView-2 and 3 WV1_PAN__MP Panchromatic (PAN) Map Scale Ortho WorldView-2 and 3 WV1_4B__2A 4-Band (4B) Standard/View Ready Standard WorldView-2, 3 and 4 WV1_4B__OR 4-Band (4B) View Ready Stereo WorldView-2, 3 and 4 WV1_4B__MP 4-Band (4B) Map Scale Ortho WorldView-2, 3 and 4 WV1_8B_2A 8-Band (8B) Standard/View Ready Standard WorldView-2 and 3 WV1_8B_OR 8-Band (8B) View Ready Stereo WorldView-2 and 3 WV1_8B_MP 8-Band (8B) Map Scale Ortho WorldView-2 and 3 WV1_S8B__2A SWIR Standard/View Ready Standard WorldView-3 WV1_S8B__MP SWIR Map Scale Ortho WorldView-3

  • Data - Announcement of Opportunity (Restrained)

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    Announcement of Opportunity for G-POD

    ESA is offering all scientists the possibility to perform bulk processing and/or validation of their own algorithms exploiting the large ESA Earth-observation archive.

  • Data - Project Proposal (Restrained)

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    WorldView-1 full archive and tasking

    WorldView-1 high resolution optical products are available as part of the Maxar Standard Satellite Imagery products from the QuickBird, WorldView-1/-2/-3/-4, and GeoEye-1 satellites. All details about the data provision, data access conditions and quota assignment procedure are described into the Terms of Applicability available in Resources section. In particular, WorldView-1 offers archive and tasking panchromatic products up to 0.50 m GSD resolution. Band Combination Data Processing Level Resolution Panchromatic Standard(2A)/View Ready STANDARD (OR2A) 50 cm, 30 cm HD View Ready Stereo 50 cm Map-Ready (Ortho) 1:12.000 Orthorectified 50 cm, 30 cm HD Native 50 cm resolution products are processed with MAXAR HD Technology to generate the 30 cm HD products: the initial special resolution (GSD) is unchanged but the HD technique increases the number of pixels and improves the visual clarity achieving aesthetically refined imagery with precise edges and well reconstructed details.

  • Data - Fast Registration with immediate access (Open)

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    ERS-1/2 Radar Altimeter REAPER Geophysical Data Record - GDR [ERS_ALT_2]

    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 1 Hz and a high rate of 20 Hz. Most 1 Hz data is also represented at 20 Hz, 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). This product is extended through Envisat RA-2 data.

  • Data - Fast Registration with immediate access (Open)

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    ERS-1/2 Radar Altimeter REAPER METEO Product - [ERS_ALT_2M]

    This is a RA Meteo product containing only the 1 Hz parameters for altimeter (surface range, satellite altitude, wind speed and significant wave height at nadir) and ATSR/MWR data (brightness temperature at 23.8 GHz and 36.5 GHz, water vapour content, liquid water content) used to correct altimeter measurements. It also contains the full geophysical corrections. This product corresponds to a subset of the REAPER GDR product (ERS_ALT_2_). 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 only the low rate of 1 Hz data. The REAPER Meteo (ERS_ALT_2M) 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). This product is extended through Envisat RA-2 data.

  • Data - Fast Registration with immediate access (Open)

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    ERS-1/2 Radar Altimeter REAPER Sensor Geophysical Data Record - SGDR [ERS_ALT_2S]

    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 1 Hz and a high rate of 20 Hz. Most 1 Hz data is also represented at 20 Hz, 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). This product is extended through Envisat RA-2 data.

  • 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 - EO Sign In Authentication (Open)

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    ERS-1/2 SAR IM Precision L1 [SAR_IMP_1P]

    The SAR Precision product is a multi-look (speckle-reduced), ground range image acquired in Image Mode. This product type is most applicable to users interested in remote sensing applications, but is also suitable for calibration purposes. The products are calibrated and corrected for the SAR antenna pattern and range-spreading loss. Radar backscatter can be derived from the products for geophysical modelling, but no correction is applied for terrain-induced radiometric effects. The images are not geocoded, and terrain distortion (foreshortening and layover) has not been removed. The numbering sequence relates to the satellite position and therefore differs between Ascending and Descending scenes. Product characteristics: Pixel size: 12.5 m (range - across track) x 12.5 m (azimuth - along track) Scene area: 100 km (range) x at least 102.5 km (azimuth) Scene size: 8000 pixels range x at least 8200 lines (azimuth) Pixel depth: 16 bits unsigned integer Total product volume: 125 MB Projection: Ground-range Number of looks: 3.

  • Data - EO Sign In Authentication (Open)

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    ERS-1/2 SAR IM Single Look Complex L1 [SAR_IMS_1P]

    The SAR SLC product is a single look complex acquired in Image Mode. It is a digital image, with slant range and phase preserved, generated from raw SAR data using up-to-date auxiliary parameters. The products are intended for use in SAR quality assessment, calibration and interferometric applications. A minimum number of corrections and interpolations are performed on the data. Absolute calibration parameters (when available) are provided in the product annotation. Product characteristics: Pixel size: 8 m (range - across track) x 4 m (azimuth - along track – varying slightly depending on acquisition Pulse Repetition Frequency) Scene area: 100 km (range) x at least 102.5 km (azimuth) Scene size: 5000 samples (range) x at least 30000 lines (azimuth) Pixel depth: 32 bits signed integer (16 bits I, 16 bits Q) Total product volume: 575 MB Projection: Slant range- Number of looks: 1.

  • Data - Fast Registration with immediate access (Open)

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    ERS-2 GOME Spectral Product L1

    GOME Level 1 products contain Earthshine radiance at the Top of the Atmosphere and solar irradiance spectra. They were generated by DLR on behalf of the European Space Agency with Level 1 GOME Data Processor (GDP-L1) starting from the Extracted GOME Calibration (EGOC) Level 0 data files. Originally raw detector signals (binary Analog to Digital Converted units) of the science measurements plus calibration constants were provided (dataset version 4 and lower), but following the end of the operational phase of the ERS-2 mission (2 July 2011), as part of ESA's post-operational algorithm improvement activities (Coldewey-Egbers et al., 2018), the GOME Level 1 data type was entirely revised and a dataset of fully calibrated and ready to use data was generated with GOME processor version 5.1. The version 5.1 data bring relevant quality improvements for the revised calibration approach, compensating aging and instrument degradation, and provide enhanced accessibility. The version 5.1 data are in NetCDF format and differ fundamentally from the previous GOME Level 1 data, having the Envisat proprietary format and basically containing Level 1a data where a dedicated extraction software tool had to be applied by end user to obtain spectrally and radiometrically calibrated radiances (including the correction for polarisation, leakage current and stray light). Such calibrations are now applied to the version 5.1 L1b data product in the standard processing. Users of GOME Level 1 products are strongly recommended to migrate to the latest reprocessed dataset. Please consult the GOME Product Quality Readme file before using the data.

  • Data - Fast Registration with immediate access (Open)

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    ERS-2 GOME Total Column Amount of Trace Gases Product

    GOME Level 2 products were generated by DLR on behalf of the European Space Agency, and are the end result of the Level 1 to 2 reprocessing campaign of GOME Level 1 version 4 data with Level 2 GOME Data Processor (GDP) version 5.0 (HDF-5 format). The GOME Level 2 data product comprises the product header, total column densities of ozone and nitrogen dioxide and their associated errors, cloud properties and selected geo-location information, diagnostics from the Level 1 to 2 algorithms and a small amount of statistical information.

  • Data - Fast Registration with immediate access (Open)

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    ERS-1/2 SCATTEROMETER Ocean Wind field and Sea Ice probability [ASPS20.H/ASPS20.N]

    The ASPS Level 2 products contain, for each node: the radar backscattering sigma nought for the three beams of the instrument, the four aliased wind solutions (Rank 1-4 wind vector) and the de-aliased wind vector flag, the sea-ice probability and sea-ice flag, the YAW quality flag. The wind retrieval is performed with the CMOD5N geophysical model function derived by ECMWF to compute the neutral winds rather than 10 m winds. ASPS L2.0 High resolution products are provided with a spatial resolution of 25x25 km and a grid spacing of 12.5 km. ASPS L2.0 Nominal resolution products are provided with a spatial resolution of 50x50 km and a grid spacing of 25 km. One product covers one orbit from ascending node crossing. Please consult the Product Quality Readme file before using the ERS ASPS data.