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Full catalog/MCD43D41
MCD43D41·v061·dataset

Uncertainty in surface reflectivity data (MODIS, daily, 1 km)

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

What it measures. An error bar, not a measurement itself: it records how much uncertainty there is in the companion data describing how the land surface reflects sunlight. Each pixel covers about a kilometer.

How it's made. Derived from 16 days of MODIS observations off NASA's Terra and Aqua satellites, processed into a daily global grid sized for climate models.

How & where you'd use it. A quality-control companion for the surface-reflectance products. Researchers use it to judge how much to trust each reflectance pixel rather than using it on its own.

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 MCD43D41 Version 6.1 Bidirectional Reflectance Distribution Function and Albedo (BRDF/Albedo) QA Uncertainty 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, each MCD43D product contains just one data layer. MCD43D41 provides BRDF inversion 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/). MCD43D41 layer contains the uncertainty range of each BRDF/Albedo pixel for the retrieval period. 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

mcd43d41_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MCD43D41",
    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.