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Using the NASA EOSDIS Common Metadata Repository

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  • CEOS Cal Val Test Site - Mauritania 2 - Pseudo-Invariant Calibration Site (PICS)

    https://cmr.earthdata.nasa.gov/search/concepts/C1220566953-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): Mauritania 2 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: 18.92 -10.42 22.67 -7.52

    USGS_LTA Short Name: CEOS_CalVal_Test_Sites-Mauritania2 Version ID: Not provided Unique ID: C1220566953-USGS_LTA

  • CEOS Cal Val Test Site - Negev, Southern Israel - Instrumented Site

    https://cmr.earthdata.nasa.gov/search/concepts/C1220567024-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. Instrumented Sites: Negev, Southern Israel is one of eight instrumented sites that are CEOS Reference Test Sites. The CEOS instrumented sites are provisionally being called LANDNET. These instrumented sites are primarily used for field campaigns to obtain radiometric gain, and these sites can serve as a focus for international efforts, facilitating traceability and inter-comparison to evaluate biases of in-flight and future instruments in a harmonized manner.  In the longer-term it is anticipated that these sites will all be fully automated and provide surface and atmospheric measurements to the WWW in an autonomous manner reducing some of the cost of a manned campaign, at present three can operate in this manner.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 30 35 30.2 35.1

    USGS_LTA Short Name: CEOS_CalVal_Test_Site-Negev-Southern_Israel Version ID: Not provided Unique ID: C1220567024-USGS_LTA

  • CEOS Cal Val Test Site - Tuz Golu, Turkey - Instrumented Site

    https://cmr.earthdata.nasa.gov/search/concepts/C1220567092-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. Instrumented Sites: Tuz Golu, Turkey is one of eight instrumented sites that are CEOS Reference Test Sites. The CEOS instrumented sites are provisionally being called LANDNET. These instrumented sites are primarily used for field campaigns to obtain radiometric gain, and these sites can serve as a focus for international efforts, facilitating traceability and inter-comparison to evaluate biases of in-flight and future instruments in a harmonized manner.  In the longer-term it is anticipated that these sites will all be fully automated and provide surface and atmospheric measurements to the WWW in an autonomous manner reducing some of the cost of a manned campaign, at present three can operate in this manner.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: 37.69 30.69 40 35.79

    USGS_LTA Short Name: CEOS_CalVal_Test_Site-Tuz_Golu-Turkey Version ID: Not provided Unique ID: C1220567092-USGS_LTA

  • CONAE SAC-C High Resolution Technological Camera (HRTC) Image Catalog

    https://cmr.earthdata.nasa.gov/search/concepts/C1214591081-SCIOPS.xml
    Description:

    [Source: NASA Facts Online, http://www.nasa.gov/centers/goddard/pdf/110896main_FS-2000-11-012-GSFC-SAS-C.pdf ] SAC-C is an international cooperative mission between NASA, the Argentine Commission on Space Activities (CONAE), Centre National d'Etudes Spatiales (CNES or the French Space Agency), Instituto Nacional De Pesquisas Espaciais (Brazilian Space Agency), Danish Space Research Institute, and Agenzia Spaziale Italiana (Italian Space Agency). SAC-C was developed through the partnership of its senior partners, CONAE and NASA with contributions from Brazil, Denmark, France, and Italy. This metadata describes the imagery from the High Resolution Technological Camera (HRTC).

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -58 -75 -18 -57

    SCIOPS Short Name: SAC-C_HRTC_DATA Version ID: Not provided Unique ID: C1214591081-SCIOPS

  • Genesis GPS Occultation Observations Level 1A

    https://cmr.earthdata.nasa.gov/search/concepts/C1214610989-SCIOPS.xml
    Description:

    The Genesis GPS Occultation Observations Level 1A data set consists of LEO-GPS (low-earth-orbiter satellites and Global Positioning System satellites) radio occultation (limb sounding) atmospheric phase delay and amplitude data for use in computing atmospheric refractivity, temperature, pressure, and water vapor profiles. LEOs collecting occultation data include GFZ's CHAMP (CHallenging Minisatellite Payload satellite) and CONAE's SAC-C. Data are available at the two GPS frequencies, 1.2 and 1.6 GHz, the latter at a time resolution of 0.01 or 0.02 seconds. These are the Level 1A products of this radio occultation data set. The full set of products available include * Level 0: Raw GPS data * GPS data for orbit determination in RINEX format * Orbit products * Level 1A: Atmospheric phase delay and signal amplitude * Level 1B: Atmospheric doppler shift and bending * Level 2: Atmospheric refractivity, temperature, pressure, water vapor pressure profiles, and comparisons to weather analysis and radiosondes. CHAMP and SAC-C each carry a JPL Blackjack GPS receiver and a rearward-facing antenna to record the signals of GPS satellites setting behind the Earth's limb as the signal passes through the atmosphere. (SAC-C also carries a forward-facing antenna, currently inactive.) Typically over 200 of these "occultations" occur per day per LEO with fairly uniform global distribution. By measuring the precise phase delay experienced by the GPS signals, and using precise clock-offset and orbit information, the atmospheric component of the phase delay can be extracted. Assuming local spherical symmetry about the tangent point, inversion of the atmospheric phase delay phase measurements during an occultation yields atmospheric refractivity profiles, which can be converted to temperature and pressure profiles between 60 km and the middle troposphere, and, with independent knowledge of temperature, into water vapor density in the middle and lower troposphere. Valuable properties of radio occultation measurements of atmospheric profiles include: * Self-calibrating, making them ideal for climate detection. * Sub-kilometer vertical resolution. * Sub-Kelvin temperature accuracy below 45 km. * All-weather operation * Independent height and pressure data allowing computation of geopotential heights and derived wind fields * Concurrent global coverage with a small constellation Comparison of CHAMP and SAC-C to National Center for Environmental Prediction (NCEP) and the European Center for Medium-range Weather Forecast (ECMWF) analyses show that GPS occultation temperature profiles are consistent with the models to better than 0.5 K in the mean, and better than 1.5 K in standard deviation. Geometric optics inversion techniques primarily use the phase delay, but physical optics inversion can also make precise use of signal amplitude variation to account for diffraction effects. Each Level 1A data file contains atmospheric phase delay and amplitude data from a single occultation at a rate of 50 or 100 samples/sec at the 1.6 GHz frequency. 1.2 GHz data is also included, but may be noisier and at a lower sample rate.

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

    SCIOPS Short Name: JPL_Genesis_L1A Version ID: Not provided Unique ID: C1214610989-SCIOPS

  • Genesis GPS Occultation Observations Level 1B

    https://cmr.earthdata.nasa.gov/search/concepts/C1214611007-SCIOPS.xml
    Description:

    The Genesis GPS Occultation Observations Level 1B data set consists of LEO-GPS (low-earth-orbiter satellites and Global Positioning System satellites) radio occultation (limb sounding) atmospheric doppler and bending data for use in computing atmospheric refractivity, temperature, pressure, and water vapor profiles. LEOs collecting occultation data include GFZ's CHAMP (CHallenging Minisatellite Payload satellite) and CONAE's SAC-C. Data are available at the two GPS frequencies, 1.2 and 1.6 GHz, at a time resolution of 1 second or better. These are the Level 1B products of this radio occultation data set. The full set of products available include * Level 0: Raw GPS data * GPS data for orbit determination in RINEX format * Orbit products * Level 1A: Atmospheric phase delay and signal amplitude * Level 1B: Atmospheric doppler shift and bending * Level 2: Atmospheric refractivity, temperature, pressure, water vapor pressure profiles, and comparisons to weather analysis and radiosondes. CHAMP and SAC-C each carry a JPL Blackjack GPS receiver and a rearward-facing antenna to record the signals of GPS satellites setting behind the Earth's limb as the signal passes through the atmosphere. (SAC-C also carries a forward-facing antenna, currently inactive.) Typically over 200 of these "occultations" occur per day per LEO with fairly uniform global distribution. By measuring the precise phase delay experienced by the GPS signals, and using precise clock-offset and orbit information, the atmospheric component of the phase delay can be extracted. Assuming local spherical symmetry about the tangent point, inversion of the atmospheric phase delay phase measurements during an occultation yields atmospheric refractivity profiles, which can be converted to temperature and pressure profiles between 60 km and the middle troposphere, and, with independent knowledge of temperature, into water vapor density in the middle and lower troposphere. Valuable properties of radio occultation measurements of atmospheric profiles include: * Self-calibrating, making them ideal for climate detection. * Sub-kilometer vertical resolution. * Sub-Kelvin temperature accuracy below 45 km. * All-weather operation * Independent height and pressure data allowing computation of geopotential heights and derived wind fields * Concurrent global coverage with a small constellation Comparison of CHAMP and SAC-C to National Center for Environmental Prediction (NCEP) and the European Center for Medium-range Weather Forecast (ECMWF) analyses show that GPS occultation temperature profiles are consistent with the models to better than 0.5 K in the mean, and better than 1.5 K in standard deviation. Smoothed atmospheric doppler and bending angle are useful intermediate products between the Levels 1A and 2 products. These products are provided at a sample rate of 1/sec or better for the 1.6 GHz frequency, and at a rate of 1/sec for the 1.2 GHz frequency. The 1.2 GHz data has lower SNR than the 1.6 GHZ data, and is used to subtract the effect of the ionosphere. Atmospheric bending with the effect of the ionosphere removed, and impact parameter are also provided. Bending angle and impact parameter are computing assuming local spherical symmetry.

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

    SCIOPS Short Name: JPL_Genesis_L1B Version ID: Not provided Unique ID: C1214611007-SCIOPS

  • Genesis GPS Occultation Observations Level 2

    https://cmr.earthdata.nasa.gov/search/concepts/C1214611008-SCIOPS.xml
    Description:

    The Genesis GPS Occultation Observations Level 2 data set contains profiles of atmospheric temperature, pressure, refractivity, and water vapor pressure with resolution of about a kilometer, derived from LEO-GPS (low-earth-orbiter satellites and satellites of the Global Positioning System) radio occultation (limb sounding) data. Similar profiles from NCEP and ECMWF analyses are also included. LEOs collecting occultation data include GFZ's CHAMP (CHallenging Minisatellite Payload satellite) and CONAE's SAC-C. These are the Level 2 products of this radio occultation data set. The full set of products available include * Level 0: Raw GPS data * GPS data for orbit determination in RINEX format * Orbit products * Level 1A: Atmospheric phase delay and signal amplitude * Level 1B: Atmospheric doppler shift and bending * Level 2: Atmospheric refractivity, temperature, pressure, water vapor pressure profiles, and comparisons to weather analysis and radiosondes. CHAMP and SAC-C each carry a JPL Blackjack GPS receiver and a rearward-facing antenna to record the signals of GPS satellites setting behind the Earth's limb as the signal passes through the atmosphere. (SAC-C also carries a forward-facing antenna, currently inactive.) Typically over 200 of these "occultations" occur per day per LEO with fairly uniform global distribution. By measuring the precise phase delay experienced by the GPS signals, and using precise clock-offset and orbit information, the atmospheric component of the phase delay can be extracted. Assuming local spherical symmetry about the tangent point, inversion of the atmospheric phase delay phase measurements during an occultation yields atmospheric refractivity profiles, which can be converted to temperature and pressure profiles between 60 km and the middle troposphere, and, with independent knowledge of temperature, into water vapor density in the middle and lower troposphere. Valuable properties of radio occultation measurements of atmospheric profiles include: * Self-calibrating, making them ideal for climate detection. * Sub-kilometer vertical resolution. * Sub-Kelvin temperature accuracy below 45 km. * All-weather operation * Independent height and pressure data allowing computation of geopotential heights and derived wind fields * Concurrent global coverage with a small constellation Comparison of CHAMP and SAC-C to National Center for Environmental Prediction (NCEP) and the European Center for Medium-range Weather Forecast (ECMWF) analyses show that GPS occultation temperature profiles are consistent with the models to better than 0.5 K in the mean, and better than 1.5 K in standard deviation.

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

    SCIOPS Short Name: JPL_Genesis_L2 Version ID: Not provided Unique ID: C1214611008-SCIOPS

  • Multispectral Medium Resolution Scanner (MMRS) coverage over the southern part of South America

    https://cmr.earthdata.nasa.gov/search/concepts/C1214611774-SCIOPS.xml
    Description:

    The MMRS camera has 5 wavelengths (0.49, 0.55, 0.66, 0.82 and 1.63 microns) and a projected pixel size of 175 meter with 8 bits depth. Swath is ~360 km wide (2000 pixels). Scenes are provided in CDs with radiometric and geometric corrections applied. The MMRS camera is on board of SAC-C satellite. SAC-C is in heliosynchronic orbit at a height of 705 km passing at 10:21 local solar time.

    Links: Temporal Extent: Spatial Extent:
    Minimum Bounding Rectangle: -57 -96 -5 -34

    SCIOPS Short Name: MMRSSACC Version ID: Not provided Unique ID: C1214611774-SCIOPS

  • UCAR COSMIC Data Analysis and Archive Center (CDAAC) CHAMP, SAC-C and GPS/MET data products

    https://cmr.earthdata.nasa.gov/search/concepts/C1214620675-SCIOPS.xml
    Description:

    The UCAR COSMIC Data Analysis and Archive Center (CDAAC) provides HAMP, SAC-C and GPS/MET data using the CDAAC 2.0 software. Data access is free, but users must submit a data agreement. Data and information available directly from the project web site include: Zenith Troposphere Comparisons, Monthly Statistics, Occultation Failure Percentages, File Inventories, and Ionosonde comparisons.

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

    SCIOPS Short Name: CDAAC_COSMIC_DATA Version ID: Version 4.0 Unique ID: C1214620675-SCIOPS