Clouds - cloud cover retrieved from infrared measurements at 10 minute intervals at CESAR observatory

Four cloud cover parameters are retrieved continuously from sky temperature measurements by a scanning infrared radiometer (NubiScope). These parameters are resp. total, low -, middle - and high level cloud cover. Only measurements 20 degrees above horizon are used to create a hemispherical cloud mask. The temperature deviation of a sky pixel from an estimated background sky temperature determines whether a pixel is considered to be cloudy or clear sky. For more information about CESAR:

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Data and Resources

Additional Info

Field Value
Author KNMI Data Services
Maintainer KNMI Data Services
Version v1.0
Last Updated July 12, 2021, 15:18 (UTC)
Created July 12, 2021, 15:18 (UTC)
Dataset name cesar_nubiscope_cldcov_la1_t10
Dataset version v1.0
East bound longitude 4.93
File identifier 5d31d1fc-c37f-4dad-8814-fafd51802e11
From 2008-05-01T00:00:00
Identifier urn:xkdc:ds:nl.knmi::cesar_nubiscope_cldcov_la1_t10/v1.0/
Linage statement Sky brightness temperatures measured in one scan are analysed with software of the manufacturer IMK ( These programmes are 'scope.exe' for realtime and 'oncemore.exe' for postprocessing. Details of the processing are proprietary and not available. Data are postprocessed with IDL routine '' before the data are published.
North bound latitude 51.97
Publication timestamp 2021-01-08T12:00:00
Purpose scientific atmospheric research
Reference system identifier EPSG28992
South bound latitude 51.97
Status onGoing
Supplemental information This dataset was orginally distributed via the CESAR Database System under the full dataset name: cesar_nubiscope_cldcov_la1_t10, v1.0
Until 2017-04-30T23:59:59
Update frequency asNeeded
Use limitation no limitations
West bound longitude 4.93