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 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.

Links:

• undefined
• undefined

Temporal Extent:

Start: 1972-09-26T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: 17.74 -10.74 21.26 -7.9

USGS_LTA Short Name: CEOS_CalVal_Test_Site-Mauritania1 Version ID: Not provided Unique ID: C1220566922-USGS_LTA

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:

• undefined
• undefined

Temporal Extent:

Start: 1972-09-15T00:00:00.000Z

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

Description:

The EOS Land Validation Core Sites are intended as a focus for land product validation over a range of biome types. These sites will provide a focus for satellite, aircraft, and ground data collection of land product validation, and will provide sites for which scientists can readily access in situ and EOS instrument data. The Mongu, Zambia EOS core validation test site provides data contributing to field experiments including the SAFARI 2000 field experiment. The following data sets are available from the core web site at: http://landval.gsfc.nasa.gov/coresite.php?SiteID=21 - ASTER data - ETM+ data from Landsat 7 - Landsat 5 GeoCover Orthorectified data - Global Land Cover Test Site (GLCTS) from EDC (LP DAAC) - MISR data from ASDC (LARC DAAC) - MODIS data from EDC (LP DAAC) - SeaWiFS data - IKONOS imagery (available through Scientific Data Purchase Program) - AERONET data See: &http://modarch.gsfc.nasa.gov/MODIS/LAND/VAL/s2k_sites.html& for other SAFARI 2000 land validation test sites.

Links:

• Data link
• Metadata link
• Metadata link
• LANDVAL_MONGU

Temporal Extent:

Start: 1970-01-01T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: -17.4 21.25 -13.4 25.25

SCIOPS Short Name: LANDVAL_MONGU Version ID: Not provided Unique ID: C1214611692-SCIOPS

Description:

This dataset contains various global lake products (1992-2019) produced by the European Space Agency (ESA) Lakes Climate Change Initiative (Lakes_cci) project. This is version 1.1 of the dataset.Lakes are of significant interest to the scientific community, local to national governments, industries and the wider public. A range of scientific disciplines including hydrology, limnology, climatology, biogeochemistry and geodesy are interested in distribution and functioning of the millions of lakes (from small ponds to inland seas), from the local to the global scale. Remote sensing provides an opportunity to extend the spatio-temporal scale of lake observation. The five thematic climate variables included in this dataset are:• Lake Water Level (LWL): a proxy fundamental to understand the balance between water inputs and water loss and their connection with regional and global climate changes.• Lake Water Extent (LWE): a proxy for change in glacial regions (lake expansion) and drought in many arid environments, water extent relates to local climate for the cooling effect that water bodies provide.• Lake Surface Water temperature (LSWT): correlated with regional air temperatures and a proxy for mixing regimes, driving biogeochemical cycling and seasonality. • Lake Ice Cover (LIC): freeze-up in autumn and advancing break-up in spring are proxies for gradually changing climate patterns and seasonality. • Lake Water-Leaving Reflectance (LWLR): a direct indicator of biogeochemical processes and habitats in the visible part of the water column (e.g. seasonal phytoplankton biomass fluctuations), and an indicator of the frequency of extreme events (peak terrestrial run-off, changing mixing conditions).Data generated in the Lakes_cci project are derived from data from multiple instruments and multiple satellites including; TOPEX/Poseidon, Jason, ENVISAT, SARAL, Sentinel, Landsat, ERS, Terra/Aqua, Suomi NPP, Metop and Orbview. For more information please see the product user guide in the documents.

Links:

• Data link
• Data link
• undefined
• ef1627f523764eae8bbb6b81bf1f7a0a

Temporal Extent:

Start: 1992-09-15T00:00:00.000Z

End: 2019-12-31T23:59:59.000Z

Spatial Extent:

Minimum Bounding Rectangle: -90 -180 90 180

FEDEO Short Name: ef1627f523764eae8bbb6b81bf1f7a0a Version ID: NA Unique ID: C2548142828-FEDEO

Description:

The Global Annual PM2.5 Grids from MODIS, MISR and SeaWiFS Aerosol Optical Depth (AOD) with GWR, 1998-2016 consist of annual concentrations (micrograms per cubic meter) of ground-level fine particulate matter (PM2.5), with dust and sea-salt removed. This data set combines AOD retrievals from multiple satellite instruments including the NASA Moderate Resolution Imaging Spectroradiometer (MODIS), Multi-angle Imaging SpectroRadiometer (MISR), and the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS). The GEOS-Chem chemical transport model is used to relate this total column measure of aerosol to near-surface PM2.5 concentration. Geographically Weighted Regression (GWR) is used with global ground-based measurements to predict and adjust for the residual PM2.5 bias per grid cell in the initial satellite-derived values. These estimates are primarily intended to aid in large-scale studies. Gridded data sets at 0.01 degrees are provided to allow users to agglomerate data as best meets their particular needs. Data sets are gridded at the finest resolution of the information sources that were incorporated, but do not fully resolve PM2.5 gradients at the gridded resolution due to influence by information sources at coarser resolutions. The data are distributed as GeoTIFF files and are in WGS 84 projection.

Links:

• Metadata link
• undefined
• Metadata link
• Data link

Temporal Extent:

Start: 1998-01-01T00:00:00.000Z

End: 2016-12-31T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: -54.85 -180 69.85 180

ESDIS Short Name: CIESIN_SEDAC_SDEI_GWRPM25_MMSAOD Version ID: 1.0 Unique ID: C3550191751-ESDIS

Search this collection...