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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 - Data Description

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    Envisat ASAR AP Co- and Cross-polar L0 [ASA_APC/APH/APV_0P]

    The ASAR Alternating Polarization Mode Level 0 (Co-polar and Cross-polar H and V) products contain time-ordered Annotated Instrument Source Packets (AISPs) corresponding to one of the three possible polarisation combinations: HH & HV, VV & VH and HH & VV, respectively. The echo samples in the AISPs have been compressed to 4 bits/sample using FBAQ. This is a high-rate, narrow swath mode, so data is only acquired for partial orbit segments. There are two co-registered images per acquisition and may be from one of seven different image swaths. The Level 0 product was produced systematically for all data acquired within this mode. Data Size: 56-100 km across track x 100 km along track. There are three AP Mode Level 0 products: ASA_APH_0P: The Cross-polar H Level 0 product corresponds to the polarisation combination HH/HV. ASA_APV_0P: The Cross-polar V Level 0 product corresponds to the polarisation combination VV/VH. ASA_APC_0P: The Co-polar Level 0 product corresponds to the polarisation combination HH/VV= H and H received/V transmit and V received.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR AP Medium Resolution L1 [ASA_APM_1P]

    This ASAR Alternating Polarization Medium Resolution Image product has been generated from Level 0 data collected when the instrument was in Alternating Polarisation Mode. The product has lower geometric resolution but higher radiometric resolution than ASA_APP and contains one or two co-registered images corresponding to one of the three polarisation combination sub modes (HH and VV, HH and HV, VV and VH). This product has been processed using the SPECAN algorithm and contains radiometric resolution good enough for ice applications and covers a continuous area along the imaging swath. The ASAR AP L0 full mission data archive has been bulk processed to Level 1 (ASA_APM_1P) in Envisat format with the IPF-ASAR processor Version 6.03. Spatial Resolution: 150 m ground range x 150 m azimuth.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR AP Single-Look Complex L1 [ASA_APS_1P]

    This product is a complex, slant-range, digital image generated from Level 0 data collected when the instrument is in Alternating Polarisation mode. (7 possible swaths). It contains two CO-registered images corresponding to one of the three polarisation combination submodes (HH and VV, HH and HV, VV and VH). In addition, the product uses the Range Doppler algorithm and the most up to date processing parameters available at the time of processing. It can be used to derive higher level products for SAR image quality assessment, calibration and interferometric applications, if allowed by the instrument acquisition. A minimum number of corrections and interpolations are performed on the data in order to allow the end-user maximum freedom to derive higher level products. Complex output data is retained to avoid loss of information. Absolute calibration parameters are available depending on external calibration activities and are provided in the product annotations. Spatial Resolution: Approximately 8m slant range x approximately 4m azimuth.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR AP Precision L1 [ASA_APP_1P]

    This ASAR Alternating Polarisation Mode Precision product is generated from Level 0 data collected when the instrument is in Alternating Polarisation Mode (7 possible swaths). The product contains two CO-registered images corresponding to one of the three polarisation combination submodes (HH and VV, HH and HV, VV and VH). This is a stand-alone multi-look, ground range, narrow swath digital image generated using the SPECAN algorithm and the most up to date auxiliary information available at the time of processing. Engineering corrections and relative calibration (antenna elevation gain, range spreading loss) are applied to compensate for well-understood sources of system variability. Generation of this product uses a technique to allow half the looks of an image to be acquired in horizontal polarisation and the other half in vertical polarisation and processed to 30-m resolution (with the exception of IS1). Absolute calibration parameters are available depending on external calibration activities and are provided in the product annotations. Spatial Resolution: 30 m ground range x 30 m azimuth.

  • Data - Data Service Request (Restrained)

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    Envisat ASAR WS L0 [ASA_WS__0P]

    The WS Mode Level 0 product consists of time-ordered AISPs collected while the instrument was is in Wide Swath Mode. The echo samples in the AISPs have been compressed to 4 bits per sample using FBAQ. This is a high-rate, wide swath (ScanSAR) mode so data is only acquired for partial orbit segments and is composed from five image swaths (SS1 to SS5). The Level 0 product is produced systematically for all data acquired within this mode. The objective of this product is to offer Level 0 data for possible image processing on another processing site. It includes mandatory information for SAR processing. Data Size: 400 km across track x 400 km along track.

  • Data - Fast Registration with immediate access (Open)

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    Envisat DORIS Doppler [DOR_DOP_1P]

    This product was generated by the Centre de Traitement Doris Poseidon (CTDP). The DORIS Doppler product (DOR_DOP_1P) was consolidated offline 2-4 weeks after sensing and stored in the F-PAC archive. The file size is 0.5 Mbytes per orbit.

  • Data - Fast Registration with immediate access (Open)

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    Envisat DORIS Precise Orbit [DOR_VOR_AX]

    The latest version of the Envisat DORIS Precise Orbit product, DOR_VOR_AX, was generated by the Centre de Traitement Doris Poseidon (CTDP) using the Geophysical Data Records F standards (GDR-F). The product is used to obtain the satellite orbital parameters (latitude, longitude, height and height rate) by using orbit computation routines. The most significant changes related to the GDR-F standards concern the new ocean tide model (FES2014) and the updated Terrestrial Reference Frame (ITRF2014). The new standards significantly improve all Precise Orbit Determination (POD) metrics with respect to GDR-E. The mean difference and variance of Sea Surface Height (SSH) at crossovers is slightly reduced. The DOR_VOR_AX product adopts the Envisat format, and the size is 0.2 Mbytes per orbit. Users are recommended to apply the GDR-F version, but the previous datasets are still available (i.e. GDR-D and GDR-E versions). See further details in the readme file for Envisat DORIS Precise Orbit Determination files. Comparison of Envisat Sea Level Anomaly trends obtained using DORIS Precise Orbit GDR-E and F standards. North/South patterns are evident. Credits: CNES/CLS.