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Full catalog/MCD43D39
MCD43D39·v061·dataset

Data-quality flags for surface reflectance (MODIS, daily)

MODIS/Terra+Aqua BRDF/Albedo QA ValidobsBand7 Daily L3 Global 30ArcSec CMG V061
land NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. Quality information rather than a measurement itself — it flags how many valid, trustworthy observations went into the surface-reflectance results for one MODIS infrared band, so users can pick out the most reliable data.

How it's made. Generated daily alongside the combined Terra and Aqua MODIS surface products, gridded globally at about 1 km resolution.

How & where you'd use it. A companion data-quality layer that researchers check before trusting the matching reflectance values; it's a behind-the-scenes aid, not a standalone product.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › ALBEDOLAND SURFACE › SURFACE RADIATIVE PROPERTIES › ANISOTROPYLAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-02-16 → ongoing
  • Measured byTerra (MODIS) · Aqua (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The MCD43D39 Version 6.1 Bidirectional Reflectance Distribution Function and Albedo (BRDF/Albedo) QA ValidObs Band 7 dataset is produced daily using 16 days of Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) data at 30 arc second (1,000 meter (m)) resolution. Data are temporally weighted to the ninth day which is reflected in the Julian date in the file name. This Climate Modeling Grid (CMG) product covers the entire globe for use in climate simulation models. Due to the large file size, MCD43D product contains just one data layer. MCD43D39 provides MODIS band 7 valid observation quality information for the MCD43D products. Users are urged to use the band specific quality flags to isolate the highest quality full inversion results for their own science applications as described in the [User Guide](https://www.umb.edu/spectralmass/modis-user-guide-v006-and-v0061/mcd43d-cmg-30-arc-second-products/). MCD43D39 contains the valid observation quality layer representing each of the 16 days of the retrieval period for MODIS band 7. Known Issues * For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=MODIS&sat=TerraAqua&as=61).

Get the data

mcd43d39_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MCD43D39",
    version="061",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.