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    • MODIS/Terra+Aqua Photosynthetically Active Radiation Daily/3-Hour L3 Global 1km SIN Grid V062

    Metadata Updated: June 4, 2024

    The MCD18A2 Version 6.2 is a Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua combined Photosynthetically Active Radiation (PAR) gridded Level 3 product produced daily at 1 kilometer pixel resolution with estimates of PAR every 3 hours. PAR is incident solar radiation in the visible spectrum (400-700 nanometers) and is an important variable in land-surface models that address a variety of scientific and application issues. The MCD18 products are based on a prototyping algorithm that uses multi-temporal signatures of MODIS data to derive surface reflectance and then calculate incident PAR using the look-up table (LUT) approach. The LUTs consider different types of loadings of aerosols and clouds at a variety of illumination/viewing geometry. Global PAR products are generated from MODIS and geostationary satellite data. Additional details regarding the methodology used to create the data are available in the Algorithm Theoretical Basis Document (ATBD) (https://lpdaac.usgs.gov/documents/106/MCD18_ATBD.pdf)).

    Provided in the MOD18A2 product are layers for instantaneous PAR array for each individual MODIS overpass and 3-hour PAR array along with a View Zenith Angle layer.

    Validation at stage 1 (https://modis-land.gsfc.nasa.gov/MODLAND_val.html) has been achieved for the MODIS Surface Radiation products. Further details regarding MODIS land product validation for the MCD18 data products are available from the MODIS Land Team Validation site (https://modis-land.gsfc.nasa.gov/ValStatus.php?ProductID=MCD18).

    The Version 6.2 Level-1B (L1B) products have been improved by undergoing various calibration changes that include: 1) MODIS shortwave infrared bands are included in the retrieval algorithm, which significantly reduces estimation uncertainties in cloud- and snow-covered pixels. 2) An improved climatology of surface reflectance was produced and used in the retrieval algorithm.

    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 March 28, 2024
    Metadata Updated Date June 4, 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 March 28, 2024
    Metadata Updated Date June 4, 2024
    Publisher LP DAAC
    Maintainer
    Identifier C2486282714-LPCLOUD
    Data First Published 2021-03-18
    Language en-US
    Data Last Modified 2021-03-18
    Category Terra, Aqua, 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 Dongdong Wang. 2024-03-07. MCD18A2.062. MODIS/Terra+Aqua Photosynthetically Active Radiation Daily/3-Hour L3 Global 1km SIN Grid V062. 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/MCD18A2.062. https://doi.org/10.5067/MODIS/MCD18A2.062. The DOI landing page provides citations in APA and Chicago styles..
    Creator Dongdong Wang
    Graphic Preview Description Browse image for Earthdata Search
    Graphic Preview File https://cmr.earthdata.nasa.gov/browse-scaler/browse_images/granules/G2800165776-LPCLOUD?h=85&w=85
    Harvest Object Id 6cd87c6a-76ec-42b7-8db2-0df2921ed196
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL https://doi.org/10.5067/MODIS/MCD18A2.062
    Metadata Type geospatial
    Old Spatial -180.0 -90.0 180.0 90.0
    Program Code 026:001
    Release Place Sioux Falls, South Dakota, USA
    Series Name MCD18A2.062
    Source Datajson Identifier True
    Source Hash c5857442d88c7c14c202bd1ae1a0dda74ba84e894d692cdd2e168a8c55d89e92
    Source Schema Version 1.1
    Spatial
    Temporal 2000-02-24T00:00:00Z/2024-06-03T00:00:00Z

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