MCD18C2: Global Daily Photosynthetically Active Radiation at 0.05 Degree Resolution

MCD18C2 Version 6.2 provides global estimates of Photosynthetically Active Radiation (PAR) every 3 hours at a 0.05-degree resolution. The National Aeronautics and Space Administration produced this combined Terra and Aqua MODIS product, which was last updated in March 2026. PAR measures incident solar radiation in the 400-700 nanometer spectrum, a critical variable for land-surface modeling.

Use Cases

• Modeling vegetation growth and carbon cycles based on incident solar radiation in the visible spectrum.
• Assessing surface energy budgets for climate studies based on 3-hour PAR estimates.
• Improving land-surface model accuracy in cloud- and snow-covered regions based on the inclusion of shortwave infrared bands.
• Analyzing diurnal patterns of solar radiation available for photosynthesis based on the 3-hour data array.

Strengths

• Algorithm improvements in Version 6.2, including the use of MODIS shortwave infrared bands, reduce estimation uncertainties.
• Data is produced daily at a global 0.05-degree (approximately 5,600-meter) spatial resolution.
• Includes a View Zenith Angle layer alongside instantaneous and 3-hour PAR arrays.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Known issues exist and require consultation of the external MODIS/VIIRS Land Quality Assessment website.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Generated from a prototyping algorithm using multi-temporal signatures of MODIS and geostationary satellite data with a look-up table approach.

Time Range

Daily production.

Freshness

Last updated 2026-03-12 23:22:16.528694; freshness should be verified.

Geography

Global coverage.