2024-03-28T11:16:28.387Zhttps://cmr.earthdata.nasa.gov/opensearch/collections.atomCMRechodev@echo.nasa.govECHO dataset metadataSearch parameters: satellite => SAC-C boundingBox => startTime => endTime => 19101https://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1000000024-CDDISCMRechodev@echo.nasa.govGEOSSEOSDISCDDIS_GNSS_satellite_dataGlobal Navigation Satellite System (GNSS) data consists of the U.S. Global Positioning System (GPS) and the Russian GLObal NAvigation Satellite System (GLONASS) (plus other international systems) data sets. The Global Positioning System, developed by the U.S. Department of Defense, has been fully operational since 1994. GPS consists of a constellation of 24 satellites and three active spares each traveling in a 12 hour circular orbit, 20,200 kilometers above the Earth. The satellites are positioned so that six are observable nearly 100 percent of the time from any point on the Earth. The GLObal NAvigation Satellite System (GLONASS), managed and deployed by the Russian Federation, is similar to the U. S. Global Positioning System (GPS) in terms of the satellite constellation, orbits, and signal structure. GNSS receivers detect, decode, and process signals from the GNSS satellites. The satellites transmit the ranging codes on two radio-frequency carriers, allowing the locations of GNSS r2012-06-14T00:00:00.000ZC1000000024-CDDIS2002-01-01T00:00:00.000Z/CDDIS_GNSS_satellite_dataCDDIS_GNSS_satellite_data1CDDISNASA/GSFC/SED/ESD/GGL/CDDISNASA/GSFC/SED/ESD/GGL/CDDIS1CARTESIAN-90 -180 90 180falsefalsefalsefalsefalsefalsefalsefalse0.65gov.nasa.eosdistruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220567099-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Algeria 3 - Pseudo-Invariant Calibration Site (PICS)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.C1220567099-USGS_LTA1972-08-11T00:00:00.000Z/CEOS Cal Val Test Site - Algeria 3 - Pseudo-Invariant Calibration Site (PICS)CEOS_CalVal_Test_Sites-Algeria3Not providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN29.09 5.22 31.36 10.01falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.native_id"CALVAL_PIS_ALGERIA_3"org.ceos.wgiss.cwic.granules.provider"USGSLSI"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220567104-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Algeria 5 - Pseudo-Invariant Calibration Site (PICS)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 5 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.C1220567104-USGS_LTA1972-08-15T00:00:00.000Z/CEOS Cal Val Test Site - Algeria 5 - Pseudo-Invariant Calibration Site (PICS)CEOS_CalVal_Test_Sites-Algeria5Not providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN29.24 -1.32 32.79 4.24falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.geoss.geoss_data-coreorg.ceos.wgiss.cwic.granules.native_id"CALVAL_PIS_ALGERIA_5"org.ceos.wgiss.cwic.granules.provider"USGSLSI"gov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566821-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Dome C, Antarctica - Instrumented SiteOn 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:
Dome C, Antarctica 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.C1220566821-USGS_LTA1972-12-06T00:00:00.000Z/CEOS Cal Val Test Site - Dome C, Antarctica - Instrumented SiteCEOS_CalVal_Test_Site-Dome_C-AntarcticaNot providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN-76.6 123 -74.5 131.18falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.ceos.wgiss.cwic.granules.native_id"CALVAL_IS_DOME_C_ANT"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566840-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Dunhuang, China - Instrumented SiteOn 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:
Dunhuang, China, 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.C1220566840-USGS_LTA1975-04-15T00:00:00.000Z/CEOS Cal Val Test Site - Dunhuang, China - Instrumented SiteCEOS_CalVal_Test_Site-Dunhuang-ChinaNot providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN39 91.98 41.45 96.52falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.geoss.geoss_data-coreorg.ceos.wgiss.cwic.granules.native_id"CALVAL_IS_DUNHUANG_CHINA"org.ceos.wgiss.cwic.granules.provider"USGSLSI"gov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566808-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Frenchman Flat, USA - Instrumented SiteOn 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:
Frenchman Flat, USA 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.C1220566808-USGS_LTA1972-08-09T00:00:00.000Z/CEOS Cal Val Test Site - Frenchman Flat, USA - Instrumented SiteCEOS_CalVal_Test_Site-Frenchman_Flat-USANot providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN36.7 -115.9 36.9 -115.8falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.ceos.wgiss.cwic.granules.native_id"CALVAL_IS_FRENCHMAN_FLAT"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566841-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Ivanpah Playa, USA - Instrumented SiteOn 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:
Ivanpah Playa, USA 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.C1220566841-USGS_LTA1972-08-26T00:00:00.000Z/CEOS Cal Val Test Site - Ivanpah Playa, USA - Instrumented SiteCEOS_CalVal_Test_Site-Ivanpah_Playa-USANot providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN35.45 -115.5 35.65 -115.3falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.ceos.wgiss.cwic.granules.native_id"CALVAL_IS_IVANPAH_PLAYA"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566843-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - La Crau, France - Instrumented SiteOn 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:
La Crau, France 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.C1220566843-USGS_LTA1972-08-16T00:00:00.000Z/CEOS Cal Val Test Site - La Crau, France - Instrumented SiteCEOS_CalVal_Test_Site-La_Crau-FranceNot providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN41.86 1.92 45.63 6.49falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.ceos.wgiss.cwic.granules.native_id"CALVAL_IS_LACRAU_FRANCE"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566868-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Libya 1 - Pseudo-Invariant Calibration Site (PICS)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):
Libya 4 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.C1220566868-USGS_LTA1973-01-15T00:00:00.000Z/CEOS Cal Val Test Site - Libya 1 - Pseudo-Invariant Calibration Site (PICS)CEOS_CalVal_Test_Site-Libya1Not providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN23.44 12.19 25.76 14.83falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.ceos.wgiss.cwic.granules.native_id"CALVAL_PIS_LIBYA_1"org.geoss.geoss_data-coregov.nasa.eosdistruetruehttps://cmr.earthdata.nasa.gov/opensearch/collections.atom?uid=C1220566922-USGS_LTACMRechodev@echo.nasa.govCEOSCWICCEOS Cal Val Test Site - Mauritania 1 - Pseudo-Invariant Calibration Site (PICS)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 1 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.C1220566922-USGS_LTA1972-09-26T00:00:00.000Z/CEOS Cal Val Test Site - Mauritania 1 - Pseudo-Invariant Calibration Site (PICS)CEOS_CalVal_Test_Site-Mauritania1Not providedUSGS_LTADOI/USGS/EROSDOI/USGS/EROSNot ProvidedCARTESIAN17.74 -10.74 21.26 -7.9falsefalsefalsefalsefalsefalsefalsefalse0.65org.ceos.wgiss.cwic.granules.prodorg.ceos.wgiss.cwic.granules.provider"USGSLSI"org.geoss.geoss_data-coreorg.ceos.wgiss.cwic.granules.native_id"CALVAL_PIS_MAURITANIA_1"gov.nasa.eosdistruetrue