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Using the NASA EOSDIS Common Metadata Repository

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  • 500 metre interval contours of Antarctica derived from ERS radar altimetry data.

    https://cmr.earthdata.nasa.gov/search/concepts/C1214308545-AU_AADC.xml
    Description:

    500 metre interval contours of the Antarctic continent derived from slope corrected orthometric heights that were captured using European Remote Sensing (ERS) radar altimetry. ESA's two European Remote Sensing (ERS) satellites, ERS-1 and 2, were launched into the same orbit in 1991 and 1995 respectively. Their payloads included a synthetic aperture imaging radar, radar altimeter and instruments to measure ocean surface temperature and wind fields. ERS-2 added an additional sensor for atmospheric ozone monitoring. The two satellites acquired a combined data set extending over two decades. The ERS-1 mission ended on 10 March 2000 and ERS-2 was retired on 05 September 2011.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -82 -180 -65 180

    AU_AADC Short Name: ERS_CONT_500_ANT Version ID: 1 Unique ID: C1214308545-AU_AADC

  • A digital terrain model of Antarctica in Triangulated Irregular Network (TIN) format, derived from ERS Radar Altimetry.

    https://cmr.earthdata.nasa.gov/search/concepts/C1214308549-AU_AADC.xml
    Description:

    An ESRI formatted triangular irregular network (TIN) of the Antarctic continental terrain, derived from ERS radar altimeter data. The data is in a Polar Stereographic projection with true scale at 71 degrees South. The TIN is unreliable in latitudes south of 82 degrees South and steep areas of the continent, particularly along the coast. ESA's two European Remote Sensing (ERS) satellites, ERS-1 and 2, were launched into the same orbit in 1991 and 1995 respectively. Their payloads included a synthetic aperture imaging radar, radar altimeter and instruments to measure ocean surface temperature and wind fields. ERS-2 added an additional sensor for atmospheric ozone monitoring. The two satellites acquired a combined data set extending over two decades. The ERS-1 mission ended on 10 March 2000 and ERS-2 was retired on 05 September 2011.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -82 -180 -65 180

    AU_AADC Short Name: ERS_DTM_TIN_ANT Version ID: 1 Unique ID: C1214308549-AU_AADC

  • Antarctic iceberg sizes and spatial distribution from SAR image analysis - Map

    https://cmr.earthdata.nasa.gov/search/concepts/C1214311458-AU_AADC.xml
    Description:

    This map shows the distribution of the iceberg data extracted from ERS SAR images. Icebergs are identified in Synthetic Aperture Radar [SAR] images by image analysis using the texture and intensity of the microwave backscatter observations. The images are segmented using an edge detecting algorithm, and segments identified as iceberg or background, which may be sea ice, open water, or a mixture of both. Dimensions of the icebergs are derived by spatial analysis of the corresponding image segments. Location of the iceberg is derived from its position within the image and the navigation data that gives the location and orientation of the image. More than 20,000 individual observations have been extracted from SAR images acquired by the European Space Agency's ERS-1 and 2 satellites and the Canadian Space Agency's Radarsat satellite. Because images can overlap, some proportion of the observations represent multiple observations of the same set of icebergs. Most observations relate to the sector between longitudes 70E and 135E. The data set includes observations from several other discrete areas around the Antarctic coast. In general observations are within 200 km of the coast but in limited areas extend to about 500 km from the coast. This metadata record has been derived from work performed under the auspices of ASAC project 2187 (ASAC_2187). The map in the pdf file shows the extent of the coverage of individual SAR scenes used in the analysis and the abundance and size characteristics (by a limited colour palette) of the identified icebergs.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -80 70 -55 135

    AU_AADC Short Name: AAD_Ant_iceberg_SAR Version ID: 1 Unique ID: C1214311458-AU_AADC

  • Antarctic surface snow grain size spatial distribution from satellite nir analysis - Map

    https://cmr.earthdata.nasa.gov/search/concepts/C1214311469-AU_AADC.xml
    Description:

    The spatial distribution of surface snow grain size over the Antarctic snow cover has been determined from analysis of near-thermal-infra-red data acquired with the ATSR-2 instrument on the European Space Agency's ERS-2 satellite. Scattering from a snow surface in the short wave infra-red part of the spectrum (0.9 to 3.5 micron) is strongly dependent on grain size, and to a lesser extent on shape. A relation between snow surface reflectance, illumination incidence-angle, and grain size, has been established using a model of BRDF [Bi-Directional Reflectance Distribution Function] for snow and laboratory measurements of the BRDF behaviour of snow. This relation is used to invert the derived values of reflectance at Top-Of-Atmosphere to grain size. TOA reflectance values are derived from satellite observations of radiance in two channels with wave-band centred at 0.87 and 1.6 micron. A ratio of the two channels is used to correct for the effect of local surface slope variation on the apparent reflectance. Grain size is determined at a regular spacing in a grid of cells, each 16 km x 16 km. The ATSR-2 instrument provides observations on a 1 km pixel, so that 256 observations are accumulated to improve signal/ratio response. Calculations are made on a per orbit basis. Cloud affected cells are detected by two methods: a variance test within the 16 km cell; and a minimum grain size criterion. Very small grain size (less than 25 micron) occurs almost exclusively in clouds. A maximum solar incidence angle of 75 degrees is imposed and relatively small viewing incidence angles are used in order to minimise possible errors that could be introduced by the BRDF effect of the snow surface and its roughness. Approximately 5400 scenes of ATSR-2 data (512 km x 512 km) were analysed. These data span the time interval from 16 November 1999 to 26 January 2000. The results are presented as a spatial distribution of grain size values on the regular array of 16 km cells. They include mean values accumulated over all orbits for the 1999-2000 summer season, together with standard deviation, and density of observations contributing to the mean. Time series of grain size values for each cell can also be extracted from the data set for the individual orbits. For the 1999-2000 austral summer season, incidence of cloud cover was very high in West Antarctica, and to a lesser extent around the near-coastal margin. Cloud cover over much of East Antarctica was low. This metadata record has been derived from work performed under the auspices of ASAC project 2200 (ASAC_2200).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -84 -180 -60 180

    AU_AADC Short Name: AAD_Ant_surf_snow_grain_size Version ID: 1 Unique ID: C1214311469-AU_AADC

  • ATSR Fire Product Over Indonesia

    https://cmr.earthdata.nasa.gov/search/concepts/C1214559939-ESA.xml
    Description:

    The Fire Product: ATSR Fire Products Over Indonesia was part of the International Geosphere-Biosphere Programme Data and Information System (IGBP-DIS) Regional Satellite Fire Data Compilation CD-ROM. A fast delivery service dedicated to fire monitoring applications has been set up at ESA/ESRIN. The nighttime acquisitions of the ATSR-2 instrument on board ERS-2 have been processed in order to visualize and localize hot spots in South East Asia. The results of the ERS-2 Indonesian fire survey are available from the ESA Earth Observation Page "http://earth.esa.int/ew/fires/indonesia_97/". The fire product consists of 83 different datasets show fire locations for different ATSR images. Two kinds of files are available for each dataset: - a GIF image file showing in lat/long projection the area, the footprint of the relevant ATSR frame and the saturated counts sensed in the 3.7 micron channel. - an ASCII location file listing for each hotspot: sample (relevant to the GIF image), line (relevant to the GIF image), latitude and longitude coordinates.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -10 100 5 120

    ESA Short Name: IGBP-DIS_FIRE_INDONESIA Version ID: Not provided Unique ID: C1214559939-ESA

  • AVISO Level 4 Absolute Dynamic Topography for Climate Model Comparison

    https://cmr.earthdata.nasa.gov/search/concepts/C1652971731-PODAAC.xml
    Description:

    This dataset contains absolute dynamic topography (similar to sea level but with respect to the geoid) binned and averaged monthly on 1 degree grids. The coverage is from October 1992 to December 2010. These data were provided by AVISO (French space agency data provider) to support the CMIP5 (Coupled Model Intercomparison Project Phase 5) under the World Climate Research Program (WCRP) and was first made available via the JPL Earth System Grid. The dynamic topography are derived from sea surface height measured by several satellites including Envisat, TOPEX/Poseidon, Jason-1 and OSTM/Jason-2, and referenced to the geoid. Along with this dataset, two additional ancillary data files are included in the same directory which contain the number of observations and standard error co-located on the same 1 degree grids.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    PODAAC Short Name: AVISO_L4_DYN_TOPO_1DEG_1MO Version ID: 1 Unique ID: C1652971731-PODAAC

  • Brightness Temperature images processed and delivered in near-real time from the AVHRR and ATSR instruments at Tromso Satellite Station

    https://cmr.earthdata.nasa.gov/search/concepts/C1214607945-SCIOPS.xml
    Description:

    Under an ESA contract TSS receives global ATSR data from the ERS-1 satellite. This is a demonstration project where data is processed in Tromso and the products are distributed directly to the end user. The UK Met. Office is one of the users having received ATSR data products from TSS. This near real-time service is set up using Internet for transmission of the products. The operational service aquires an average of 10 ERS-1 passes a day, every day throughout the year. Through this near real-time demonstration project, the TSS infrastructure has proven to be very well suited for supporting an operational service with useful and necessary information. A full resolution ATSR data product chain has also been implemented very recently. TSS can now offer in near-real time full resolution (1 km) brightness and sea surface temperature products. The coverage is global for the ATSR, and for the AVHRR the coverage is that of TSS (i.e. Europe).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 50 -55 90 110

    SCIOPS Short Name: BT_images Version ID: Not provided Unique ID: C1214607945-SCIOPS

  • CDDIS_SLR_data

    https://cmr.earthdata.nasa.gov/search/concepts/C1000000041-CDDIS.xml
    Description:

    In Satellite Laser Ranging (SLR), a short pulse of coherent light generated by a laser (Light Amplification by Stimulated Emission of Radiation) is transmitted in a narrow beam to illuminate corner cube retroreflectors on the satellite. The return signal, typically a few photons, is collected by a telescope and the time-of-flight is measured. Using information about the satellite's orbit, the time-of-flight, and the speed of light, the location of the ranging station can be determined. Similar data acquired by another station, many kilometers distant from the first, or on a different continent, can be used to determine the distance between stations to precisions of centimeters or better. Repetitive measurements over months and years yield the change in distance, or the motion of the Earth's crust.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    CDDIS Short Name: CDDIS_SLR_data Version ID: 1 Unique ID: C1000000041-CDDIS

  • CDDIS_SLR_predictions

    https://cmr.earthdata.nasa.gov/search/concepts/C1000000025-CDDIS.xml
    Description:

    Predicted satellite orbits for Satellite Laser Ranging (SLR) tracking of satellites equipped with corner cube retroreflectors. SLR stations download these prediction files and coordinate tracking schedules for satellite acquisition. The predicted orbit files typically contain orbit information for multiple days and are issued on a daily or sub-daily basis.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -90 -180 90 180

    CDDIS Short Name: CDDIS_SLR_predictions Version ID: 1 Unique ID: C1000000025-CDDIS

  • CEOS Cal Val Test Site - Algeria 3 - Pseudo-Invariant Calibration Site (PICS)

    https://cmr.earthdata.nasa.gov/search/concepts/C1220567099-USGS_LTA.xml
    Description:

    On the background of these requirements for sensor calibration, intercalibration and product validation, the subgroup on Calibration and Validation of the Committee on Earth Observing System (CEOS) formulated the following recommendation during the plenary session held in China at the end of 2004, with the goal of setting-up and operating an internet based system to provide sensor data, protocols and guidelines for these purposes: Background: Reference Datasets are required to support the understanding of climate change and quality assure operational services by Earth Observing satellites. The data from different sensors and the resulting synergistic data products require a high level of accuracy that can only be obtained through continuous traceable calibration and validation activities. Requirement: Initiate an activity to document a reference methodology to predict Top of Atmosphere (TOA) radiance for which currently flying and planned wide swath sensors can be intercompared, i.e. define a standard for traceability. Also create and maintain a fully accessible web page containing, on an instrument basis, links to all instrument characteristics needed for intercomparisons as specified above, ideally in a common format. In addition, create and maintain a database (e.g. SADE) of instrument data for specific vicarious calibration sites, including site characteristics, in a common format. Each agency is responsible for providing data for their instruments in this common format. Recommendation : The required activities described above should be supported for an implementation period of two years and a maintenance period over two subsequent years. The CEOS should encourage a member agency to accept the lead role in supporting this activity. CEOS should request all member agencies to support this activity by providing appropriate information and data in a timely manner. Pseudo-Invariant Calibration Sites (PICS): Algeria 3 is one of six CEOS reference Pseudo-Invariant Calibration Sites (PICS) that are CEOS Reference Test Sites. Besides the nominally good site characteristics (temporal stability, uniformity, homogeneity, etc.), these six PICS were selected by also taking into account their heritage and the large number of datasets from multiple instruments that already existed in the EO archives and the long history of characterization performed over these sites. The PICS have high reflectance and are usually made up of sand dunes with climatologically low aerosol loading and practically no vegetation. Consequently, these PICS can be used to evaluate the long-term stability of instrument and facilitate inter-comparison of multiple instruments.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 29.09 5.22 31.36 10.01

    USGS_LTA Short Name: CEOS_CalVal_Test_Sites-Algeria3 Version ID: Not provided Unique ID: C1220567099-USGS_LTA