55aa94abf6bf40fab87143f24849ac89 English 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646 34e75e7e8e838b0f3ee5916856d510b4 dataset NERC EDS Centre for Environmental Data Analysis 01235446432 RAL Space STFC Rutherford Appleton Laboratory, Harwell Campus Didcot OX11 0QX United Kingdom support@ceda.ac.uk pointOfContact 2026-04-15T18:45:08 UK GEMINI 2.3 WGS 84 MOD021KM - Level 1B Calibrated Radiances - 1km 2021-04-15T14:05:21 publication 2021-04-15T14:05:21 creation https://catalogue.ceda.ac.uk/uuid/55aa94abf6bf40fab87143f24849ac89 55aa94abf6bf40fab87143f24849ac89 National Aeronautics and Space Administration (NASA) These data are a copy of MODIS data from the NASA Level-1 and Atmosphere Archive & Distribution System (LAADS) Distributed Active Archive Center (DAAC). The copy is potentially only a subset. Below is the description from https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/MOD021KM "The MODIS Level-1B data set contains calibrated and geolocated at-aperture radiances for 36 discrete bands located in the 0.4 µm to 14.4 µm region of the electromagentic spectrum. These data are generated from MODIS Level-1A scans of raw radiance, and in the process are converted to geophysical units of W/(m2µm sr). In addition, the Bidirectional Reflectance Distribution Function (BRDF) may be determined for the solar reflective bands (1-19, 26) through knowledge of the solar irradiance (e.g., determined from MODIS solar diffuser data, and from the target illumination geometry). Additional data are provided including quality flags, error estimates and calibration data. Visible, shortwave infrared, and near infrared measurements are only made during the daytime, while radiances for the thermal infrared region (bands 20-25, 27-36) are measured continuously. The resolution of channels 1 and 2 is 250 m, channels 3 through 7 are 500m resolution, and the rest are 1 km resolution. However, for the MODIS L1B 1 km product, the 250 m and 500 m band radiance data and their associated uncertainties have been aggregated to 1 km resolution. Thus, the entire channel data set is referenced to the same spatial and geolocation scales. Separate L1B products are available for just the 250 m channels (MOD02QKM) and the 500 m channels (MOD02HKM) that preserve the original resolution of the data. Spatial resolution for pixels at nadir is 1 km, degrading to 4.8 km in the along-scan direction at the scan extremes. However, thanks to the overlapping of consecutive swaths and the respective pixels there, the resulting resolution at the scan extremes is about 2 km. A 55 degree scanning pattern at the EOS orbit of 705 km results in a 2330 km orbital swath width with global coverage every one to two days. A single MODIS Level-1B granule will nominally contain a scene built from 203 scans (or swaths) sampled 1354 times in the cross-track direction, corresponding to approximately 5 minutes worth of data. Since an individual MODIS scan (or swath) will contain 10 along-track spatial elements, the scene will be composed of 1354 by 2030 pixels, resulting in a spatial coverage of 2330 km by 2030 km. Due to the MODIS scan geometry, there will be increasing overlap occurring beyond about a 25 degree scan angle. Users requiring the full-resolution geolocation and solar/satellite geometry can obtain the separate MODIS Level-1 Geolocation product (MOD03) from LAADS." Shortname: MOD021KM , Platform: Terra , Instrument: MODIS , Processing Level: Level-1B , Spatial Resolution: 1 km , Temporal Resolution: 5 minute , ArchiveSets: 61, 6 , Collection: MODIS Collection 6.1 - Level 1, Atmosphere, Land (ArchiveSet 61) , PGE Number: PGE02 , File Naming Convention: MOD021KM.AYYYYDDD.HHMM.CCC.YYYYDDDHHMMSS.hdf AYYYYDDD = Acqusition Year and Day of Year HHMM = Hour and Minute of acquisition CCC = Collection number YYYYDDDHHMMSS = Production Date and Time YYYYDDD = Year and Day of Year of acquisition , Citation: MODIS Characterization Support Team (MCST), 2017. MODIS 1km Calibrated Radiances Product. NASA MODIS Adaptive Processing System, Goddard Space Flight Center, USA: http://dx.doi.org/10.5067/MODIS/MOD021KM.061 , Keywords: Climate Change, Radiance National Aeronautics and Space Administration (NASA) author USA unknown author NERC EDS Centre for Environmental Data Analysis custodian 01235446432 RAL Space STFC Rutherford Appleton Laboratory, Harwell Campus Didcot OX11 0QX United Kingdom support@ceda.ac.uk custodian NERC EDS Centre for Environmental Data Analysis distributor 01235446432 RAL Space STFC Rutherford Appleton Laboratory, Harwell Campus Didcot OX11 0QX United Kingdom support@ceda.ac.uk distributor National Aeronautics and Space Administration (NASA) principal_investigator USA unknown principalInvestigator NERC EDS Centre for Environmental Data Analysis point_of_contact 01235446432 RAL Space STFC Rutherford Appleton Laboratory, Harwell Campus Didcot OX11 0QX United Kingdom support@ceda.ac.uk pointofContact National Aeronautics and Space Administration (NASA) publisher USA unknown publisher asNeeded dataset Climate Change Radiance orthoimagery theme GEMET - INSPIRE themes, version 1.0 2008-06-01 publication otherRestrictions Public data: access to these data is available to both registered and non-registered users. otherRestrictions Under the following licence https://modaps.modaps.eosdis.nasa.gov/services/faq/LAADS_Data-Use_Citation_Policies.pdf, appropriate use of these data may fall under unclassified use. This message is intended as guidance, always read the full licence. When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record. grid English imageryBaseMapsEarthCover -180.0 180.0 -90.0 90.0 2000-02-23T23:55:00 HDF NERC EDS Centre for Environmental Data Analysis Data Center Contact 01235446432 RAL Space STFC Rutherford Appleton Laboratory, Harwell Campus Didcot OX11 0QX United Kingdom support@ceda.ac.uk distributor https://catalogue.ceda.ac.uk/uuid/55aa94abf6bf40fab87143f24849ac89 CEDA Data Catalogue Page Detail and access information for the resource information http://data.ceda.ac.uk/neodc/modis/data/MOD021KM DOWNLOAD Download Data download https://ladsweb.modaps.eosdis.nasa.gov/search/order/2/MOD021KM--61 LAADS DAAC - Search for Product Files No further details. information https://ladsweb.modaps.eosdis.nasa.gov/archive/allData/61/MOD021KM/ LAADS DAAC - Data Archive No further details. information https://ladsweb.modaps.eosdis.nasa.gov/filespec/MODIS/61/MOD021KM LAADS DAAC - Collection 61 File Specification No further details. information http://dx.doi.org/10.5067/MODIS/MOD021KM.061 LAADS DAAC DOI: 10.5067/MODIS/MOD021KM.061 No further details. information dataset Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 Data were downloaded from https://ladsweb.modaps.eosdis.nasa.gov/archive/allData/ to support UK research groups, especially NCEO.