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  • Data (12)
  • News (9)
  • Events (11)
  • Tools (1)
  • Activities (1)
  • Documents (3)
  • Document - General Reference

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    Envisat-ASAR-science-and-applications.pdf

    This document describes the technical specifications of the Envisat ASAR instrument and its operations and objectives.

  • Document - Proceedings

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    EO-Summer-School-5-Microwave-remote-sensing-of-soil-moisture.pdf

    This presentation from ESA's EO Summer School 5 describes microwave remote sensing of soil moisture

  • Event - Conference

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    3rd ERS Symposium

    The ESA Directorate for Observation of the Earth and its Environment held the 3rd ERS Symposium, in 1997, where many of the results from the ERS-1 and ERS-2 missions were presented and discussed by the scientific community.

  • Event - Workshop

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    POLinSAR 2005

    The objectives of the POLinSAR 2005 workshop was to present the latest studies and results of SAR polarimetry and polarimetric interferometry.

  • Event - Workshop

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    POLinSAR 2007

    The POLinSAR 2007 workshop was open to ESA Principal Investigators and co-investigators, scientists and students working in the field of SAR Polarimetry and Polarimetric Interferometry, and to representatives from national, European and international space agencies and value adding industry.

  • Event - Workshop

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    2nd Space for Hydrology Workshop

    The workshop aimed to assess the current stage of knowledge and activities in space-based hydrological observations and to exchange knowledge and know how with hydrologists and researchers.

  • Event - Workshop

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    POLinSAR 2009

    The 2009 workshop focused on theory and methods in the fields of SAR Polarimetry and Polarimetric Interferometry

  • Event - Conference

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    Living Planet Symposium 2019

    ESA's Living Planet Symposia are amongst the biggest Earth observation conferences in the world. Scientists present their latest findings on Earth's environment and climate.

  • Data - Campaigns (Open)

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    SPARC

    ESA's SPectra bARrax Campaign (SPARC) activity was part of the preparatory study for a proposed ESA Earth Explorer mission called SPECTRA. The objective was to collect a CHRIS/PROBA reference dataset for SPECTRA-related studies.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR WS Medium Resolution L1 [ASA_WSM_1P]

    The strip-line product has been generated from Level 0 data collected when the instrument was in Wide Swath Mode. The product includes slant range to ground range corrections and covers a continuous area along the imaging swath. It is intended to perform application oriented analysis on large scale phenomena over a wide region and for multi-temporal imaging. This is the standard product for ASAR Wide Swath Mode. The ASAR WS L0 full mission data archive has been bulk processed to Level 1 (ASA_WSM_1P) in Envisat format with the IPF-ASAR processor Version 6.03. Spatial Resolution: 150 m slant range x 150 m azimuth.

  • 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 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 - 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 Global Monitoring L1 [ASA_GM1_1P]

    This product has been generated from Level 0 data collected when the instrument was in Global Monitoring Mode. One product covers a full orbit. The product includes slant range to ground range corrections. This strip-line product is the standard for ASAR Global Monitoring Mode. It is processed to approximately 1 km resolution using the SPECAN algorithm. The swath width is approximately 400 km. The ASAR GM L0 full mission data archive has been bulk processed to Level 1 (ASA_GM1_1P) in Envisat format with the IPF-ASAR processor Version 6.03. Spatial Resolution: 1 km ground range x 1 km azimuth.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR IM Medium Resolution L1 [ASA_IMM_1P]

    This ASAR Medium Resolution strip-line product has been generated from Level 0 data collected when the instrument was in Image Mode. This product has lower resolution but higher radiometric resolution than the ASA_IMP. It is intended to perform applications-oriented analysis on large scale phenomena and multi-temporal imaging. This product provides a continuation of the ERS-SAR Image Mode data. The ASAR IM L0 full mission data archive has been bulk processed to Level 1 (ASA_IMM_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 IM Precision L1 [ASA_IMP_1P]

    This is a multi-look, ground range, digital Precision Image generated from Level 0 data collected when the instrument was in Image Mode (7 possible swaths HH or VV polarisation). The product includes slant range to ground range correction. It is for users wishing to perform applications-oriented analysis and applies to multi-temporal imaging and to derive backscattering coefficients. The stand-alone image is generated using the Range/Doppler algorithm. The processing uses up to date (at time of processing) auxiliary parameters corrected for antenna elevation gain, and range spreading loss. Engineering corrections and relative calibration are applied to compensate for well-understood sources of system variability. Absolute calibration parameters, when available (depending on external calibration activities) are provided in the product annotations. This product provides a continuation of the ERS-SAR_PRI product. Spatial Resolution: 30 m ground range x 30 m azimuth.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR IM Single Look Complex L1 [ASA_IMS_1P]

    This data product represents a single-look, complex, slant-range, digital image generated from Level 0 ASAR data collected when the instrument is in Image Mode. Seven possible swaths in HH or VV polarisation are available. The product is primarily intended for use in SAR quality assessment and calibration or applications requiring complex SAR images such as interferometry, and can be used to derive higher level products. The spatial coverage is about 100 km along track per 56 - 100 km across track, and the radiometric resolution is 1 look in azimuth, 1 look in range. The file size is 741 Mbytes. It is worth highlighting that Azimuth pixel spacing depends on Earth-Satellite relative velocity and actual PRF and slant range pixel spacing is given by ASAR sampling frequency (19.208 Mhz). Auxiliary data include: Orbit state vector, Time correlation parameters, Main Processing parameters ADS, Doppler Centroid ADS, Chirp ADS, Antenna Elevation Pattern ADS, Geolocation Grid ADS, SQ ADS. Spatial Resolution: Approximately 8m slant range x approximately 4m 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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    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.

  • Event - Training

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    4th Advanced Training Course in Land Remote Sensing

    ESA organised the 4th Advanced Training Course in Land Remote Sensing which took place in Athens, Greece from 1 to 5 July 2013