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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
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 - Fast Registration with immediate access (Open)
Envisat ASAR Wave Imagette Cross Spectra L1 [ASA_WVS_1P]
The ASAR Wave product is extracted from the combined SLC and Cross Spectra product, ASA_WVI_1P, which is generated from data collected when the instrument was in Wave Mode using the Cross Spectra methodology. The product is meant for Meteo users. The spatial coverage is up to 20 spectra acquired every 100 km, with a minimum coverage of 5km x 5km. The file size has a maximum of 0.2 Mbytes. Auxiliary data include Orbit state vector, Time correlation parameters, Wave Processing parameters ADS, Wave Geolocation ADS, SQ ADS. The product provides a continuation of the ERS-SAR wave mode data. Output: Wavelength range from 20 to 1000 m in 24 logarithmic steps.
Data - Fast Registration with immediate access (Open)
Envisat ASAR WM Ocean Wave Spectra L2 [ASA_WVW_2P]
The ASAR Wave Mode product is created by inverting the cross-spectra which is computed from inter-look processing of the SLC wave imagettes in order to derive the directional ocean product ocean wave spectra. Auxiliary ADSs included with the product remains the same as for the ASAR Wave Mode Cross-Spectra product. The output follows the format of the Envisat ASAR Level 1B Wave Mode Imagette Cross-Spectra (ASA_WVS_1P) product. This is done in order to be compatible with the ground segment products of Envisat ASAR. This product provides a continuation of the ERS-SAR wave mode data. Output: Wavelength range from 20 to 1000 m in 24 logarithmic steps.
Data - EO Sign In Authentication (Open)
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)
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)
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 - Fast Registration with immediate access (Open)
Envisat ASAR Wave SLC and Cross-Spectra Imagettes L1 [ASA_WVI_1P]
This is the basic Level 1B ASAR Wave Mode product, including up to 400 single-look, complex, slant range, imagettes generated from Level 0 data and up to 400 imagette power spectra computed using the cross-spectra methodology. The auxiliary parameters used are the most up-to-date at the time of processing. A minimum number of corrections and interpolations are performed 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, when available (depending on external calibration activities), are provided in the product annotations. Imagette power spectrum is equivalent to the ERS UWA (Near Real Time) product with revisited algorithm (cross-spectra) taking into account the higher quality of the SLC imagette. Note that starting from an SLC imagette, the generation of an ERS UWA-type product might be ensured by a simple look detection and summation. This product provides a continuation of the ERS-SAR wave mode data. Imagette Spatial Resolution: 20 m ground range x 20 m azimuth. Cross Spectra Output: Wavelength range from 20 to 1000 m in 24 logarithmic steps.
Data - Data Service Request (Restrained)
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 - EO Sign In Authentication (Open)
Envisat MERIS Full Resolution - Level 1 [MER_FRS_1P/ME_1_FRG]
The MERIS Level 1 Full Resolution (FR) product contains the Top of Atmosphere (TOA) upwelling spectral radiance measurements. The in-band reference irradiances for the 15 MERIS bands are computed by averaging the in-band solar irradiance of each pixel. The in-band solar irradiance of each pixel is computed by integrating the reference solar spectrum with the band-pass of each pixel. The MERIS FR Level 1 product has Sentinel 3-like format starting from the 4th reprocessing data released to users in July 2020. Each measurement and annotation data file is in NetCDF 4. The Level 1 product is composed of 22 data files: 15 files containing radiances at each band (one band per file), accompanied by the associated error estimates, and 7 annotation data files. The 15 sun spectral flux values provided in the instrument data file of the Level 1 products are the in-band reference irradiances adjusted for the Earth-sun distance at the time of measurement. The band-pass of each pixel is derived from on-ground and in-flight characterisation via an instrument model. The values "Band wavelength" and "Bandwidth" provided in the Manifest file of the Level 1b products are the averaged band-pass of each pixel over the instrument field of view. Auxiliary data are also listed in the Manifest file associated to each product. The Level 1 FR product covers the complete instrument swath. The product duration is not fixed and it can span up to the time interval of the input Level 0 (for a maximum of 20 minutes). Thus the estimated size of the Level 1 FR is dependent on the start/stop time of the acquired segment. During the Envisat mission, acquisition of MERIS Full Resolution data was subject to dedicated planning based on on-demand ordering and coverage of specific areas according to operational recommendations and considerations. See yearly and global density maps to get a better overview of the MERIS FR coverage.
Data - EO Sign In Authentication (Open)
Envisat MERIS Full Resolution - Level 2 [MER_FRS_2P/ME_2_FRG]
MERIS FR Level 2 is a Full-Resolution Geophysical product for Ocean, Land and Atmosphere. Each MERIS Level 2 geophysical product is derived from a MERIS Level 1 product and auxiliary parameter files specific to the MERIS Level 2 processing. The MERIS FR Level 2 product has Sentinel 3-like format starting from the 4th reprocessing data released to users in July 2020. The data package is composed of NetCDF 4 files containing instrumental and scientific measurements, and a Manifest file which contains metadata information related to the description of the product. A Level 2 product is composed of 64 measurement files containing: 13 files containing Water-leaving reflectance, 13 files containing Land surface reflectance and 13 files containing the TOA reflectance (for all bands except those dedicated to measurement of atmospheric gas - M11 and M15), and several files containing additional measurements on Ocean, Land and Atmospheric parameters and annotation. The Auxiliary data used are listed in the Manifest file associated to each product. The Level 2 FR product covers the complete instrument swath. The product duration is not fixed and it can span up to the time interval of the input Level 0/Level 1. Thus the estimated size of the Level 2 FR is dependent on the start/stop time of the acquired segment. During the Envisat mission, acquisition of MERIS Full Resolution data was subject to dedicated planning based on on-demand ordering and coverage of specific areas according to operational recommendations and considerations. See yearly and global density maps to get a better overview of the MERIS FR coverage.