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    • MODIS/Terra Land Surface Temperature/3-Band Emissivity 8-Day L3 Global 1km SIN Grid V061

    Metadata Updated: May 27, 2024

    A suite of Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature and Emissivity (LST&E) products are available in Collection 6.1. The MOD21 Land Surface Temperature (LST) algorithm differs from the algorithm of the MOD11 (https://doi.org/10.5067/modis/mod11_l2.061) LST products, in that the MOD21 algorithm is based on the ASTER Temperature/Emissivity Separation (TES) technique, whereas the MOD11 uses the split-window technique. The MOD21 TES algorithm uses a physics-based algorithm to dynamically retrieve both the LST and spectral emissivity simultaneously from the MODIS thermal infrared bands 29, 31, and 32. The TES algorithm is combined with an improved Water Vapor Scaling (WVS) atmospheric correction scheme to stabilize the retrieval during very warm and humid conditions.

    The MOD21A2 dataset is an 8-day composite LST product that uses an algorithm based on a simple averaging method. The algorithm calculates the average from all the cloud free MOD21A1D (http://doi.org/10.5067/MODIS/MOD21A1D.061) and MOD21A1N (http://doi.org/10.5067/MODIS/MOD21A1N.061) daily acquisitions from the 8-day period. Unlike the MOD21A1 data sets where the daytime and nighttime acquisitions are separate products, the MOD21A2 contains both daytime and nighttime acquisitions as separate Science Dataset (SDS) layers within a single Hierarchical Data Format (HDF) file. The LST, Quality Control (QC), view zenith angle, and viewing time have separate day and night SDS layers, while the values for the MODIS emissivity bands 29, 31, and 32 are the average of both the nighttime and daytime acquisitions. Additional details regarding the method used to create this Level 3 (L3) product are available in the Algorithm Theoretical Basis Document (ATBD (https://lpdaac.usgs.gov/documents/1399/MOD21_ATBD.pdf)).

    Validation at stage 1 (https://modis-land.gsfc.nasa.gov/MODLAND_val.html) has been achieved for the MODIS Land Surface Temperature and Emissivity data products. Further details regarding MODIS land product validation for the MOD21 data products are available from the MODIS Land Team Validation site (https://modis-land.gsfc.nasa.gov/ValStatus.php?ProductID=MOD21).

    Improvements/Changes from Previous Versions

    • The Version 6.1 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: changes to the response-versus-scan angle (RVS) approach that affects reflectance bands for Aqua and Terra MODIS, corrections to adjust for the optical crosstalk in Terra MODIS infrared (IR) bands, and corrections to the Terra MODIS forward look-up table (LUT) update for the period 2012 - 2017.
    • A polarization correction has been applied to the L1B Reflective Solar Bands (RSB).
    • The product utilizes GEOS data replacing MERRA2.
    • Three new CMG products are available in the MxD21 suite (MxD21C1/C2/C3).

    Access & Use Information

    Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

    Downloads & Resources

    Dates

    Metadata Created Date May 30, 2023
    Metadata Updated Date May 27, 2024

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Graphic Preview

    Browse image for Earthdata Search

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date May 30, 2023
    Metadata Updated Date May 27, 2024
    Publisher LP DAAC
    Maintainer
    Identifier C2565791040-LPCLOUD
    Data First Published 2021-02-08
    Language en-US
    Data Last Modified 2021-02-08
    Category Terra, geospatial
    Public Access Level public
    Bureau Code 026:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Metadata Catalog ID https://data.nasa.gov/data.json
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Citation Glynn Hulley, Simon Hook. 2021-02-08. MODIS/Terra Land Surface Temperature/3-Band Emissivity 8-Day L3 Global 1km SIN Grid V061. Sioux Falls, South Dakota, USA. Archived by National Aeronautics and Space Administration, U.S. Government, NASA EOSDIS Land Processes Distributed Active Archive Center. https://doi.org/10.5067/MODIS/MOD21A2.061. https://doi.org/10.5067/MODIS/MOD21A2.061. The DOI landing page provides citations in APA and Chicago styles..
    Creator Glynn Hulley, Simon Hook
    Graphic Preview Description Browse image for Earthdata Search
    Graphic Preview File https://cmr.earthdata.nasa.gov/browse-scaler/browse_images/granules/G2630796535-LPCLOUD?h=85&w=85
    Harvest Object Id 4c72cc7f-11a0-4031-b6c9-a4f10fb90888
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL https://doi.org/10.5067/MODIS/MOD21A2.061
    Metadata Type geospatial
    Old Spatial -180.0 -90.0 180.0 90.0
    Program Code 026:001
    Release Place Sioux Falls, South Dakota, USA
    Source Datajson Identifier True
    Source Hash 25c595d31adfc2fbce2b1188ab2b519e0763fd382bcfb29e3afbeabad1c6426d
    Source Schema Version 1.1
    Spatial
    Temporal 2000-02-18T00:00:00Z/2024-05-27T00:00:00Z

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