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  • All Categories (37)
  • Data (16)
  • News (6)
  • Missions (1)
  • Events (12)
  • Campaigns (1)
  • Documents (1)
  • 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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    Applications of the ERS Along Track Scanning Radiometer Workshop 1999

    The workshop on ERS mission's Along Track Scanning Radiometer (ATSR) instrument gathered researchers and specialists working on different applications of the mission.

  • Event - Workshop

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    CEOS-IVOS Workshop on Inter-comparison of Large Scale Optical and Infrared Sensors

    The 2004 workshop was an opportunity to present and exchange experiences and knowledge from work on inter-comparing large scale optical sensors at different product levels.

  • Event - Conference

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    15 Years of Progress in Radar Altimetry Symposium

    A Symposium on "15 Years of Progress in Radar Altimetry" and the annual meeting of the Ocean Surface Topography Science Team, the International Doris Service Workshop and the ARGO Workshop.

  • Event - Training

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    Advanced Training Course on Ocean Remote Sensing 2006

    The objective of the course was to provide first-hand information on a broad range of ocean research topics including key principles of SAR, Radar Altimetry, Ocean Colour and Sea Surface Temperature measurements, processing algorithms, data products and their use in oceanographic applications.

  • News - General News

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    Satellite Radar Altimetry: past and future

    Satellite radar altimetry measurements yield a wealth of information that can be used for a wide range of applications.

  • Event - Meeting

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    20th GHRSST Science Team Meeting

    The 20th GHRSST International Science Team meeting in 2019 brought together sea surface temperature experts to look at future innovations.

  • Campaign

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    AirScatterGNSS

    In this project an Airborne Wind Vector Scatterometer (AWVS) system was designed and built for measurements of sea surface backscattering from an aircraft.

  • Data - Campaigns (Open)

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    AirScatterGNSS

    In this project an Airborne Wind Vector Scatterometer (AWVS) system was designed and built for measurements of sea surface backscattering from an aircraft.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Averaged Surface Temperature [AT1/AT2_AR__2P]

    The Averaged Surface Temperature Product (AST) contains averaged geophysical data at two different resolutions, and with respect to two different averaging schemes: measurement data sets at resolutions of 0.5 by 0.5 degrees and 10 by 10 arcmin with respect to a latitude/longitude grid; other data sets contain data averaged over equal area cells of 50 by 50 km and 17 by 17 km aligned with the satellite ground track. Both top-of-atmosphere and surface data sets are provided. The surface temperature data sets provide, for sea cells, nadir and dual view sea surface temperatures, and for land cells, land surface temperature (currently 11 micron BT) and NDVI. Cloud data is also included. No ADS are included in the AST product; auxiliary data is contained within the MDS. The data sets of the AST product are arranged by surface type and resolution. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - Data Description

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    ERS-1/2 ATSR Meteo Product [AT1/AT2_MET_2P]

    The data is a fast delivery Meteo product designed for use by meteorological offices, and contains averaged BT and SST at 10 arc minute resolution. The single MDS comprises the fields of MDS#3 (SST record, 10 arc min cell) of the AST product, with the addition of Average Brightness Temperature (ABT) fields (BT/TOA sea record, 10 arc min cell) to make it more self-contained. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - Data Description

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    ERS-1/2 ATSR ARC L2P/L3U [UPA-L2P_GHRSST/L3U_GHRSST]

    The L2P product contains full resolution dual-view Sea Surface Temperature (SST) values. These SST use the ARC SST retrieval and cloud screening which differ from the methods used to produce the Gridded Surface Temperature (ATS_NR__2P) products. In addition to SST, the L2P products contain the ATSR Saharan Dust Index (ASDI) and the clear-sky probability estimated by the ARC cloud detection algorithm. The L2P processor also generates L3U products; these are the L2P products averaged onto a regular grid at 0.1 degree resolution (they are therefore similar to the AR / Meteo Envisat-format products). The L2P and L3U products are provided in NetCDF-4 format following GHRSST Data Specifications (GDS) v2. The L2P/L3U archive has been reprocessed with a new processor based upon the ARC SST; the changes are outlined in full in the L2P Reprocessing User Note.

  • Data - External Data (Restrained)

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    ERS-1/2 ATSR ARC Level 3 products [AT1/AT2_AVG_3PAARC]

    The recommended ATSR Level 3 products for Sea Surface Temperature (SST) applications are the ARC (ATSR Re-processing for Climate) Level 3 products. ARC reprocesses the ATSR multi-mission archive using new cloud detection and SST retrievals to produce a homogenous record of sea surface temperature. The main ARC objective is to reduce regional biases in retrieved SST to less than 0.1 K for all global oceans while creating a very homogenous record with a stability (lack of drift in the observing system and analysis) of 0.05 K per decade. ARC products are available for ATSR-1, ATSR-2 and AATSR. ARC products are provided in netCDF format and contain data for both the skin SST and the SST estimated for depths of 0.2 and 1.0 m (corresponding approximately to drifter and moored buoy depths). The AATSR estimated depth SSTs are adjusted to a local equatorial crossing time of 10:30 (approximately half an hour after observation), to provide continuity with ATSR-1 and ATSR-2 data. The ARC project was led by Chris Merchant (University of Reading, formerly of the University of Edinburgh) and funded by NERC and the UK Government.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Gridded Surface Temperature [AT1/AT2_NR__2P]

    The Gridded Surface Temperature (GST) Product is the Level 2 full resolution geophysical product. The product contains gridded sea-surface temperature images using both nadir and dual view retrieval algorithms. The product includes pixel latitude/longitude positions, X/Y offset and the results of the cloud-clearing/land-flagging. It contains a single measurement data set the content of which is switchable, that is to say, the content of each pixel field will depend on the surface type. Specifically, the contents of the data fields will depend on the setting of the forward and nadir cloud flags and the land flag. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - Fast Registration with approval (Restrained)

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    ERS-1/2 ATSR Gridded Brightness Temperature/Reflectance [AT1/AT2_TOA_1P]

    The Gridded Brightness Temperature/Reflectance (GBTR) product contains top of atmosphere (TOA) brightness temperature (BT) values for the infra-red channels and reflectance values for the visible channels. Values for each channel and for the nadir and forward views occupy separate measurement data sets. Additional MDS contain cloud and land/sea flags and confidence flags for each image pixel. The 3rd reprocessing of ATSR data was performed in 2013; the processing updates that have been put in place and the scientific improvements are outlined in full in the User Summary Note for the Third ERS ATSR Reprocessing.

  • Data - EO Sign In Authentication (Open)

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    Envisat ASAR WS Single Look Complex L1 [ASA_WSS_1P]

    The Level-1B data product offered by ESA from the ASAR Wide-Swath Mode (WS) is a multi-look detected product, ASA_WSM_1P, intended to support applications that exploit intensity data. In order to support the development of new applications with the ASAR ScanSAR data, a WSM product providing phase information has been developed and implemented in the ESA ASAR processor - the Wide-Swath Single-Look complex product (ASA_WSS_1P). This product is mainly used for INSAR applications based either on wide-swath/wide-swath pairs or wide-swath/image mode pairs, applications of ocean current mapping, large-area ocean wave retrievals and atmospheric water vapour characterisation. It is important to mention that the standard ESA WSS product is based on the prototype WSS processor developed by Polimi/Poliba, which has also been used to generate prototype products for testing potential and preparing the exploitation of the WSS product. The ESA ASA_WSS_1P product is available as a standard Envisat ASAR product. The ASA_WSS_1P product format is slightly different from other ASAR products since: There are 5 different MDSs, one per sub-swath A "Doppler Grid" ADS has been included to support ocean current mapping applications There are 5 records in the MPP ADS, one per sub-swath There are 5 records in the SQ ADS, one per sub-swath. Other key characteristics of the ASA_WSS_1P product are summarised below: Processing is fully phase preserving Data in the MDSs is sampled in a common grid both in range and in azimuth Standard product is 60 sec long with 80 m az. pixel spacing Auxiliary timeline information has been added in the Main Processing Parameters ADS Elevation antenna pattern correction is applied by default (although the product is a single-look complex). Spatial Resolution: Approximately 8 m slant range x 80 m azimuth.

  • Data - Fast Registration with immediate access (Open)

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    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 - Data Description

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    GRACE-A and GRACE-B Level 1B, Level 1B combined and Level 2 Data Products

    Level-1A Data Products are the result of a non-destructive processing applied to the Level-0 data at NASA/JPL. The sensor calibration factors are applied in order to convert the binary encoded measurements to engineering units. Where necessary, time tag integer second ambiguity is resolved and data are time tagged to the respective satellite receiver clock time. Editing and quality control flags are added, and the data is reformatted for further processing. The Level-1A data are reversible to Level-0, except for the bad data packets. This level also includes the ancillary data products needed for processing to the next data level. The Level-1B Data Products are the result of a possibly destructive, or irreversible, processing applied to both the Level-1A and Level-0 data at NASA/JPL. The data are correctly time-tagged, and data sample rate is reduced from the higher rates of the previous levels. Collectively, the processing from Level-0 to Level-1B is called the Level-1 Processing. This level also includes the ancillary data products generated during this processing, and the additional data needed for further processing. The Level-2 data products include the static and time-variable (monthly) gravity field and related data products derived from the application of Level-2 processing at GFZ, UTCSR and JPL to the previous level data products. This level also includes the ancillary data products such as GFZ's Level-1B short-term atmosphere and ocean de-aliasing product (AOD1B) generated during this processing. GRACE-A and GRACE-B Level-1B Data Product: Satellite clock solution [GA-OG-1B-CLKDAT, GB-OG-1B-CLKDAT, GRACE CLKDAT]: Offset of the satellite receiver clock relative to GPS time, obtained by linear fit to raw on-board clock offset estimates GPS flight data [GA-OG-1B-GPSDAT, GB-OG-1B-GPSDAT, GRACE GPSDAT]: Preprocessed and calibrated GPS code and phase tracking data edited and decimated from instrument high-rate (10 s (code) or 1 s (phase)) to low-rate (10 s) samples for science use (1 file per day, level-1 format) Accelerometer Housekeeping data [GA-OG-1B-ACCHKP, GB-OG-1B-ACCHKP, GRACE ACCHKP]: Accelerometer proof-mass bias voltages, capacitive sensor outputs, instrument control unit (ICU) and sensor unit (SU) temperatures, reference voltages, primary and secondary power supply voltages (1 file per day, level-1 format) Accelerometer data [GA-OG-1B-ACCDAT, GB-OG-1B-ACCDAT, GRACE ACCDAT]: Preprocessed and calibrated Level-1B accelerometer data edited and decimated from instrument high-rate (0.1 s) to low-rate (1s) samples for science use (1 file per day, level-1 format) Intermediate clock solution [GA-OG-1B-INTCLK, GB-OG-1B-INTCLK, GRACE INTCLK]: derived with GIPSY POD software (300 s sample rate) (1 file per day, GIPSY format) Instrument processing unit (IPU) Housekeeping data [GA-OG-1B-IPUHKP, GB-OG-1B-IPUHKP, GRACE IPUHKP]: edited and decimated from high-rate (TBD s) to low-rate (TBD s) samples for science use (1 file per day, level-1 format) Spacecraft Mass Housekeeping data [GA-OG-1B-MASDAT, GB-OG-1B-MASDAT, GRACE MASDAT]: Level 1B Data as a function of time GPS navigation solution data [GA-OG-1B-NAVSOL, GB-OG-1B-NAVSOL, GRACE NAVSOL]: edited and decimated from instrument high-rate (60 s) to low-rate (30 s) samples for science use (1 file per day, level-1 format) OBDH time mapping to GPS time Housekeeping data [GA-OG-1B-OBDHTM, GB-OG-1B-OBDHTM, GRACE OBDHTM]: On-board data handling (OBDH) time mapping data (OBDH time to receiver time Star camera data [GA-OG-1B-SCAATT, GB-OG-1B-SCAATT, GRACE SCAATT]: Preprocessed and calibrated star camera quaternion data edited and decimated from instrument high-rate (1 s) to low-rate (5 s) samples for science use (1 file per day, level-1 format) Thruster activation Housekeeping data [GA-OG-1B-THRDAT, GB-OG-1B-THRDAT, GRACE THRDAT]: GN2 thruster data used for attitude (10 mN) and orbit (40 mN) control GN2 tank temperature and pressure Housekeeping data [GA-OG-1B-TNKDAT, GB-OG-1B-TNKDAT, GRACE TNKDAT]: GN2 tank temperature and pressure data Oscillator frequency data [GA-OG-1B-USODAT, GB-OG-1B-USODAT, GRACE USODAT]: derived from POD product GRACE-A and GRACE-B Combined Level-1B Data Product Preprocessed and calibrated k-band ranging data [GA-OG-1B-KBRDAT, GB-OG-1B-KBRDAT, GRACE KBRDAT]: range, range-rate and range-acceleration data edited and decimated from instrument high-rate (0.1 s) to low-rate (5 s) samples for science use (1 file per day, level-1 format) Atmosphere and Ocean De-aliasing Product [GA-OG-1B-ATMOCN, GB-OG-1B-ATMOCN, GRACE ATMOCN]: GRACE Atmosphere and Ocean De-aliasing Product. GRACE Level-2 Data Product: GAC [GA-OG-_2-GAC, GB-OG-_2-GAC, GRACE GAC]: Combination of non-tidal atmosphere and ocean spherical harmonic coefficients provided as average over certain time span (same as corresponding GSM product) based on level-1 AOD1B product (1file per time span, level-2 format) GCM [GA-OG-_2-GCM, GB-OG-_2-GCM, GRACE GCM]: Spherical harmonic coefficients and standard deviations of the long-term static gravity field estimated by combination of GRACE satellite instrument data and other information for a dedicated time span (multiple years) and spatial resolution (1 file per time span, level-2 format) GAB [GA-OG-_2-GAB, GB-OG-_2-GAB, GRACE GAB]: Non-tidal ocean spherical harmonic coefficients provided as average over certain time span (same as corresponding GSM product) based on level-1 AOD1B product (1file per time span, level-2 format) GAD [GA-OG-_2-GAD, GB-OG-_2-GAD, GRACE GAD]: bottom pressure product - combination of surface pressure and ocean (over the oceans, and zero over land). Spherical harmonic coefficients provided as average over certain time span (same as corresponding GSM product) based on level-1 AOD1B product (1file per time span, level-2 format) GSM [GA-OG-_2-GSM, GB-OG-_2-GSM, GRACE GSM]: Spherical harmonic coefficients and standard deviations of the static gravity field estimated from GRACE satellite instrument data only for a dedicated time span (e.g. weekly, monthly, multiple years) and spatial resolution (1 file per time span, level-2 format).

  • Data - Data Description

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    ERS-1/2 Radar Altimeter REAPER METEO Product - [ERS_ALT_2M]

    This is a RA Meteo product containing only the 1 Hz parameters for altimeter (surface range, satellite altitude, wind speed and significant wave height at nadir) and ATSR/MWR data (brightness temperature at 23.8 GHz and 36.5 GHz, water vapour content, liquid water content) used to correct altimeter measurements. It also contains the full geophysical corrections. This product corresponds to a subset of the REAPER GDR product (ERS_ALT_2_). The REAPER (REprocessing of Altimeter Products for ERS) product is generated by applying a similar processing as for Envisat RA-2 on the Level 1b consolidated waveforms using 4 different re-trackers, RA calibration improvement, new precise orbit solution (POD), new ionospheric corrections (NICO09 until 1998 and GIM up to 2003), ECMWF ERA-interim model and updated SSB tables. This product contains only the low rate of 1 Hz data. The REAPER Meteo (ERS_ALT_2M) is a global product including data over ocean, ice and land. It should be noted that this product differs from the Envisat RA2 in the following ways: The product format; which is NetCDF (more details can be found in the Product Handbook), and not PDS The product is delivered based on orbit acquisition and not per pass (pole-to-pole). This product is extended through Envisat RA-2 data.

  • Data - Fast Registration with immediate access (Open)

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    Envisat RA-2 Geophysical Data Record - GDR [RA2_GDR__2P]

    This is a RA-2 Geophysical Data Record (GDR) Full Mission Reprocessing (FMR) V3 product containing radar range and orbital altitude, wind speed, wave height, water vapour from the MWR and geophysical corrections. This FMR follows the first Envisat Altimetry reprocessing Version (V2.1) completed in 2012. The GDR and S-GDR data products were reprocessed for all cycles from 6 to 113 (May 2002 to April 2012) into a homogeneous standard in NetCDF format (close to Sentinel-3). For many aspects, the V3.0 reprocessed data are better than the previous dataset: In terms of available and valid data, the coverage is better, notably thanks to a better availability of MWR data at the beginning of the mission In terms of performance at cross-overs, the quality is improved: the annual signal and average of Mean SSH is decreased, as well as the standard deviation The new MWR characteristics were shown to improve largely the global quality of data. As well as the new tide model, the new MSS and the new orbit standard The Global and regional Mean Sea Level trend is very weakly impacted though the effort was put, this time, on the mesoscale restitution, rather than long term drift, as during V2.1 reprocessing. Please consult the Envisat RA-2/MWR Product Quality Readme file PDF before using the data.