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- Data (11)
- News (9)
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- Events (6)
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Document - Newsletter
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
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
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
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 - Success Stories
Commercial and international data for fire monitoring
As climate change sparks a surge in the frequency and intensity of wildfires, satellite data disseminated through ESA’s Third Party Missions (TPM) programme are helping scientists to track and investigate these potentially damaging natural events.
News - Thematic area articles
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
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 - Events and Proceedings
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
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
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.
Data - EO Sign In Authentication (Open)
Landsat 8 Collection 2 European Coverage
This dataset contains the European coverage of Landsat-8 Collection 2 data, both Level-1 and Level-2, acquired since the beginning of the mission. Landsat-8 Collection 2 is the result of a reprocessing effort on the archive and on newly acquired products with significant improvement with respect to Collection 1 on data quality, obtained by means of advancements in data processing and algorithm development. Primarily, this involves a relevant improvement in the absolute geolocation accuracy (now re-baselined to the European Space Agency Copernicus Sentinel-2 Global Reference Image (GRI) but also includes updated digital elevation modelling sources, improved Radiometric Calibration (even correction for the TIRS striping effect), enhanced Quality Assessment Bands, updated and consistent metadata files and usage of Cloud Optimised Georeferenced (COG) Tagged Image File Format. Landsat-8 Level-1 products combine data from the two Landsat instruments, OLI and TIRS. The Level-1 products generated can be either L1TP or L1GT: L1TP - Level-1 Precision Terrain (Corrected) (L1T) products: Radiometrically calibrated and orthorectified using ground control points (GCPs) and digital elevation model (DEM) data to correct for relief displacement. The highest quality Level-1 products suitable for pixel-level time series analysis. GCPs used for L1TP correction are derived from the Global Land Survey 2000 (GLS2000) data set. L1GT - Level-1 Systematic Terrain (Corrected) (L1GT) products: L1GT data products consist of Level-0 product data with systematic radiometric, geometric and terrain corrections applied and resampled for registration to a cartographic projection, referenced to the WGS84, G873, or current version. The dissemination server contains three different classes of Level-1 products Real Time (RT): Newly acquired Landsat-8 OLI/TIRS data are processed upon downlink but use an initial TIRS line-of-sight model parameters; the data are made available in less than 12 hours (4-6 hours typically). Once the data have been reprocessed with the refined TIRS parameters, the products are transitioned to either Tier 1 or Tier 2 and removed from the Real-Time tier (in 14-16 days). Tier 1 (T1): Landsat scenes with the highest available data quality are placed into Tier 1 and are considered suitable for time-series analysis. Tier 1 includes Level-1 Precision and Terrain (L1TP) corrected data that have well-characterized radiometry and are inter-calibrated across the different Landsat instruments. The georegistration of Tier 1 scenes is consistent and within prescribed image-to-image tolerances of ≦ 12-metre radial root mean square error (RMSE). Tier 2 (T2): Landsat scenes not meeting Tier 1 criteria during processing are assigned to Tier 2. Tier 2 scenes adhere to the same radiometric standard as Tier 1 scenes, but do not meet the Tier 1 geometry specification due to less accurate orbital information (specific to older Landsat sensors), significant cloud cover, insufficient ground control, or other factors. This includes Systematic Terrain (L1GT) and Systematic (L1GS) processed data. Landsat-8 Level-2 products are generated from L1GT and L1TP Level-1 products that meet the <76 degrees Solar Zenith Angle constraint and include the required auxiliary data inputs to generate a scientifically viable product. The data are available a couple of days after the Level-1 T1/T2. The Level-2 products generated can be L2SP or L2SR: L2SP - Level-2 Science Products (L2SP) products: include Surface Reflectance (SR), Surface Temperature (ST), ST intermediate bands, an angle coefficients file, and Quality Assessment (QA) Bands. L2SR - Level-2 Surface Reflectance (L2SR) products: include Surface Reflectance (SR), an angle coefficients file, and Quality Assessment (QA) Bands; it is generated if ST could not be generated. Two different categories of Level-1 products are offered: LC with Optical, Thermal and Quality Map images, LO with Optical and Quality Map images (Thermal not available). For the Level-2 data, only LC combined products are generated.
Event - Workshop
Envisat Validation Workshop 2002
The workshop covered various aspects of validation of the Envisat instruments.
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.
News - Infographics
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)
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 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 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)
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)
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)
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.