Description:

The Operational Sea Surface Temperature and Sea Ice Analysis Reprocessed (OSTIA-REP) is a GHRSST reprocessed Level-4 sea surface temperature and ice-concentration analysis produced by the UK Met Office (UKMO) using optimal interpolation (OI) on a global 0.05 degree grid. It is a sister product of the Near Real Time version (OSTIA-NRT), but incorporates satellite data from over 25 different SST sensors as well as in situ data from drifting and moored buoys. The OSTIA-REP is produced on a biannual frequency when more satellite and climatology observations are available from existing geostationary IR, and polar orbiting IR and MW satellites in addition to the data used in OSTIA-NRT. While OSTIA-NRT is produced to mainly serve as a lower boundary condition in Numerical Weather Prediction (NWP) models, this OSTIA-REP aims to provide a more accurate and consistent record of SST measurements over time, which is crucial for detecting long-term climate trends and variability. Both versions follow GHRSST Data Processing Specification (GDS) version 2 format guidelines. Data to June 2022 are also distributed through the E.U. Copernicus Marine Service Information (https://marine.copernicus.eu/, DOI: https://doi.org/10.48670/moi-00168 with the following license). Please refer to the user guide for more information.

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Temporal Extent:

Start: 1982-01-01T00:00:00.000Z

End: 2024-01-01T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: -90 -180 90 180

POCLOUD Short Name: OSTIA-UKMO-L4-GLOB-REP-v2.0 Version ID: 2.0 Unique ID: C2586786218-POCLOUD

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Description:

This dataset contains Daily Snow Cover Fraction of viewable snow from AVHRR, produced by the Snow project of the ESA Climate Change Initiative programme. Snow cover fraction viewable (SCFV) indicates the area of snow viewable from space over land surfaces. In forested areas this refers to snow viewable on top of the forest canopy. The SCFV is given in percentage (%) per pixel. The global SCFV product is available at about 5 km pixel size for all land areas, excluding Antarctica and Greenland ice sheets. The coastal zones of Greenland are included.The SCFV time series provides daily products for the period 1979-2023. The product V4.0 is based on EUMETSAT Fundamental Data Record (FDR) medium resolution optical satellite data from the Advanced Very High Resolution Radiometer (AVHRR). Clouds are masked using the CLARA-A3 cloud product. The retrieval method of the snow_cci SCFV product from AVHRR data has been further developed and improved based on the ESA GlobSnow approach described by Metsämäki et al. (2015) and complemented with a pre- and post-classification module. All cloud free pixels are then used for the snow extent mapping, using spectral bands centred at about 0.63 µm and 1.61 µm (channel 3a or the reflective part of channel 3b (ref3b)), and an emissive band centred at about 10.8 µm. The snow_cci snow cover mapping algorithm is a three-step approach: first, a strict pre-classification is applied to identify all cloud free pixels which are certainly snow free. For all remaining pixels, the snow_cci SCFV retrieval method is applied. Finally, a post-processing removes erroneous snow pixels caused either by falsely classified clouds in the tropics or by unreliable ref3b values at a global scale. The following auxiliary data set is used for product generation: ESA CCI Land Cover from 2000; water bodies and permanent snow and ice areas are masked based on this dataset. Both classes were separately aggregated to the pixel spacing of the SCF product. Water areas are masked if more than 50 percent of the pixel is classified as water, permanent snow and ice areas are masked if more than 50 percent are identified as such areas in the aggregated map. RMSE is retrieved from a statistical model and added as pixel-wise information.The SCFV product is aimed to serve the needs for users working in the cryosphere and climate research and monitoring activities, including the detection of variability and trends, climate modelling and aspects of hydrology, meteorology and biology.The Remote Sensing Research Group of the University of Bern, in cooperation with Gamma Remote Sensing is responsible for the SCFV product development and generation. ENVEO (ENVironmental Earth Observation IT GmbH) developed and prepared all auxiliary data sets used for the product generation. The SCFV AVHRR product comprises a few data gaps in 1979 – 1986 (1979: 22.-24.Feb.; 01.-07.Oct.; 03.-04.Nov.; 07.Nov.; 17.-18.Nov.; 1980: 22.-27.Feb.; 01.March; 03.March; 15.-20.March; 30.March – 02.April; 26.-29.June; 12.-19.July; 12.-18.Dec.; 1981: 09.-11.May; 01.-03.Aug.; 14.-23.Aug.; 1982: 28.- 31.May; 25.-26. Oct.; 1983: 27.- 31. July; 01.- 02. and 06. Aug.; 1984: 14.-15.Jan.; 06. Dec.; 1985: 01.- 24.Feb; 1986: 15. March), resulting in a 99% data coverage over the entire study period of 43 years.

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Temporal Extent:

Start: 1979-01-01T00:00:00.000Z

End: 2023-12-31T23:59:59.000Z

Spatial Extent:

Minimum Bounding Rectangle: -90 -180 90 180

FEDEO Short Name: 3c71c04cf08a410fac2c680cbf88cfd7 Version ID: NA Unique ID: C4017534711-FEDEO

Description:

Level-1B description This collection is composed of AVHRR L1B products (1.1 km) reprocessed from the NOAA POES and Metop AVHRR sensors data acquired at the University of Dundee and University of Bern ground stations and from the ESA and University of Bern data historical archive. The product format is the NOAA AVHRR Level 1B that combines the AVHRR data from the HRPT stream with ancillary information like Earth location and calibration data which can be applied by the user. Other appended parameters are time codes, quality indicators, solar and satellite angles and telemetry. Two data collections cover Europe and the neighbouring regions in the period of 1 January 1981 to 31 December 2020 and the acquired data in the context of the 1-KM project in the ‘90s. During the early 1990’s various groups, including the International Geosphere-Biosphere Programme (IGBP), the Commission of the European Communities (CEC), the Moderate Resolution Imaging Spectrometer (MODIS) Science Team and ESA concluded that a global land 1 KM AVHRR data set would have been crucial to study and develop algorithms for several land products for the Earth Observing System. USGS, NOAA, ESA and other non-U.S. AVHRR receiving stations endorsed the initiative to collect a global land 1-km multi-temporal AVHRR data set over all land surfaces using NOAA's TIROS "afternoon" polar-orbiting satellite. On 1 April 1992, the project officially began up to the end of 1999 with the utilisation of 23 stations worldwide plus the NOAA local area coverage (LAC) on-board recorders. The global land 1-km AVHRR dataset is composed of 5 channels, raw AVHRR dataset at 1.1 km resolution from the NOAA-11 and NOAA-14 satellites covering land surfaces, inland water and coastal areas. Level-1C Description This data collection consists of measurements from the Advanced Very High Resolution Radiometer (AVHRR) at 1.1km full Local Area Coverage (LAC) resolution. It is based on the ESA AVHRR Level 1B European Data Set, a curated collection of AVHRR 1km data from 1981 to 2020 covering Europe, selected areas in Africa and the acquired data out-of-Europe in the context of the 1-KM project in the ‘90s (see the Level-1B description for details). The AVHRR LAC measurements were processed by the Remote Sensing Research Group of the University Bern, Switzerland. A landmark based navigation correction software adjusted time and satellite attitude to improve the georeferencing accuracy. The PyGAC software was used to convert the counts to reflectances for the visible and near-infrared channels 1, 2, 3A, and to brightness temperatures for the infrared channels 3B, 4, 5. The infrared calibration uses on-board calibration data and is satellite specific without cross-calibration between satellites. Due to the lack of on-board calibration data for the visible channels calculated coefficients from the CIMSS PATMOS-X project, version 2017r1, were used for the visible calibration aiming to minimize spectral differences among the various AVHRR sensors. The data format is NetCDF. The calibrated AVHRR data are accompanied by coordinates, satellite and solar angles, additional metadata, and basic quality indicators. The NOAA nomenclature is used for the data record labelling it as a set of AVHRR L1C data.

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Temporal Extent:

Start: 1981-01-01T00:00:00.000Z

End: 2020-12-31T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: 35 -30 90 70

ESA Short Name: AVHRRLocalAreaCoverageImagery10 Version ID: 10.0 Unique ID: C3325394521-ESA

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: 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.

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Temporal Extent:

Start: 1975-04-15T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: 39 91.98 41.45 96.52

USGS_LTA Short Name: CEOS_CalVal_Test_Site-Dunhuang-China Version ID: Not provided Unique ID: C1220566840-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: 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.

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Temporal Extent:

Start: 1972-08-26T00:00:00.000Z

Spatial Extent:

Minimum Bounding Rectangle: 35.45 -115.5 35.65 -115.3

USGS_LTA Short Name: CEOS_CalVal_Test_Site-Ivanpah_Playa-USA Version ID: Not provided Unique ID: C1220566841-USGS_LTA