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  • Data (13)
  • News (9)
  • Missions (1)
  • Events (5)
  • Documents (2)
  • Document - Newsletter

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    Earth Online Newsletter - 08 March 2024

    This issue of the Earth Online Newsletter covers a selection of the latest news and events from ESA.

  • News - Data Release news

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    FDR4ALT - ESA unveils new cutting-edge ERS/Envisat Altimeter and Microwave Radiometer Datasets

    The European Space Agency (ESA) has developed a comprehensive suite of innovative Earth system data records as part of the Fundamental Data Records for Altimetry project - FDR4ALT.

  • News - Operational News

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    Temporary interruption to Envisat AATSR dissemination service

    A planned downtime will affect the access to the ftp dissemination server for the Envisat AATSR data during the period 13-15 February 2024.

  • News - Thematic area articles

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    Space data support Earth’s ecosystems

    ESA’s Earth observation (EO) missions are making a critical contribution to monitoring transformations in our planet’s ecosystems, helping track changes in the vegetation, soil, and ocean that affect these systems.

  • News - Thematic area articles

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    Global understanding of Earth's land surfaces greatly boosted by satellite data

    ESA perform land surface monitoring with a range of instruments onboard satellites acquiring optical and radar data. Collections of data from these missions are freely available for research purposes.

  • Event - Training

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    EO Summer School 5

    ESA's series of summer schools, on Monitoring of the Earth System, aims to promote the exploitation of Earth observation data.

  • News - Thematic area articles

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    Space helps monitor Earth’s changing biosphere

    Earth’s biosphere is continually changing. Through its pioneering Earth observation missions, ESA is making critical contributions to monitor these changes and their impacts on Earth’s water and carbon cycles.

  • News - Events and Proceedings

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    Data preservation takes centre stage at Living Planet Symposium

    Against the backdrop of the famed Rhine River, world-class scientists and Earth observation data-users are gathered this week in the historical city of Bonn, at the Living Planet Symposium (LPS).

  • News - Success Stories

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    How Envisat helped to shape global understanding of Earth’s systems

    Twenty years have passed since a ground-breaking European spacecraft designed to deliver unprecedented insight into the planet’s changing environment was lofted into orbit.

  • News - Thematic area articles

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    Satellite data boost global understanding of land surface

    Understanding our changing land surface is essential in the study of climate change. Satellites are used to monitor changes to the material that covers Earth’s surface, so-called land cover, such as vegetation and water.

  • Event - Workshop

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    Envisat Validation Workshop 2002

    The workshop covered various aspects of validation of the Envisat instruments.

  • 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.

  • News - Infographics

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    Envisat - ESA's versatile Earth observation satellite

    Learn more about ESA's Envisat mission - the largest Earth observation satellite ever built - in a new infographic.

  • Data - EO Sign In Authentication (Open)

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    JERS-1 SAR Level 1 Precision Image

    The JSA_PRI_1P product is comparable to the ESA PRI/IMP images generated for Envisat ASAR and ERS SAR instruments. It is a ground range projected detected image in zero-Doppler SAR coordinates, with a 12.5 metre pixel spacing. It has four overlapping looks in Doppler covering a total bandwidth of 1000Hz, with each look covering a 300Hz bandwidth. Sidelobe reduction is applied to achieve a nominal PSLR of less than -21dB. The image is not geocoded, and terrain distortion (foreshortening and layover) has not been removed. Data acquired by ESA ground stations. Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service.

  • Data - EO Sign In Authentication (Open)

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    JERS-1 SAR Level 1 Single Look Complex Image

    The JSA_SLC_1P product is comparable to the ESA SLC/IMS images generated for Envisat ASAR and ERS SAR instruments. It is a slant-range projected complex image in zero-Doppler SAR coordinates. The data is sampled in natural units of time in range and along track, with the range pixel spacing corresponding to the reciprocal of the platform ADC rate and the along track spacing to the reciprocal of the PRF. Data is processed to an unweighted Doppler bandwidth of 1000Hz, without sidelobe reduction. The product is suitable for interferometric, calibration and quality analysis applications. Data acquired by ESA ground stations. Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service.

  • Data - EO Sign In Authentication (Open)

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    JERS-1 OPS (Optical Sensor) Very Near Infrared Radiometer (VNIR) System Corrected Products level 1

    The JERS-1 Optical System (OPS) is composed of a Very Near Infrared Radiometer (VNIR) and a Short Wave Infrared Radiometer (SWIR). The instrument has 8 observable spectral bands from visible to short wave infrared. Data acquired by ESA ground stations The JERS-1 OPS products are available in GeoTIFF format. These products are available only for the VNIR sensor. All four bands are corrected. The correction consists in a vertical and horizontal destriping, the radiometry values are expanded from the range [0.63] to the range [0.255]. No geometrical correction is applied on level 1. The pixel size of approximately 18 x 24.2 metres for raw data is newly dimensioned to 18 x 18 metres for System Corrected data using a cubic convolution algorithm. Disclaimer: Cloud coverage for JERS OPS products has not been computed using an algorithm. The cloud cover assignment was performed manually by operators at the acquisition stations. Due to missing attitude information, the Nadir looking band (band 3) and the corresponding forward looking band (band 4) are not well coregistered, resulting in some accuracy limitations. The quality control was not performed systematically for each frame. A subset of the entire JERS Optical dataset was selected and manually checked. As a result of this, users may occasionally encounter issues with some of the individual products. Spatial coverage: Check the spatial coverage of the collection on a map available on the Third Party Missions Dissemination Service.

  • 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.