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MODIS/Terra+Aqua Photosynthetically Active Radiation Daily/3-Hour L3 Global 1km SIN Grid V061

Metadata Updated: June 4, 2024

The MCD18A2 Version 6.1 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 6.1 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 MCD18A2 Version 6.1 product has an improved 1 km resolution over the 5 km Version 6.
  • The MCD18 suite has added CMG products (MCD18C1/MCD18C2).

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 June 4, 2024

Metadata Source

Harvested from NASA Data.json

Graphic Preview

Browse image for Earthdata Search

Additional Metadata

Resource Type Dataset
Metadata Created Date May 30, 2023
Metadata Updated Date June 4, 2024
Publisher LP DAAC
Maintainer
Identifier C2484080763-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. 2021-03-18. MODIS/Terra+Aqua Photosynthetically Active Radiation Daily/3-Hour 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/MCD18A2.061. https://doi.org/10.5067/MODIS/MCD18A2.061. 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/G2555640973-LPCLOUD?h=85&w=85
Harvest Object Id 6d023690-5b9b-4b8f-8bc4-0e2dcfdf5641
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://doi.org/10.5067/MODIS/MCD18A2.061
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 3acbb3b94196b3257ec590ac2bc54399a1fe0e93a8bad75f743d29deeacf044e
Source Schema Version 1.1
Spatial
Temporal 2000-02-24T00:00:00Z/2024-06-03T00:00:00Z

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