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Full catalog/VJ143C1
VJ143C1·v002·dataset

Reflectance model settings per pixel (NOAA-20, daily, 5 km)

VIIRS/JPSS1 BRDF/Albedo Model Parameters Daily L3 Global 0.05Deg CMG V002
land NASA LPCLOUD Level 3 active HDF-EOS5
In plain English

What it measures. Not a finished map but the per-pixel model settings that describe how each spot on the land reflects light from different angles, on a 5-km global grid.

How it's made. Derived from the VIIRS instrument on the NOAA-20 satellite over a 16-day window; these are the fitted parameters of a reflectance model for each pixel.

How & where you'd use it. An intermediate building block used to produce the matching albedo and adjusted-reflectance products; most people use those finished products rather than these parameters directly.

What's measured

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

Coverage & cadence

  • Time span2018-01-05 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS5
  • 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 NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Bidirectional Reflectance Distribution Function (BRDF) and Albedo Model Parameters Daily Global 0.05 Degree Climate Modeling Grid (CMG) Version 2 product (VJ143C1) is derived from the 30 arc second CMG VJ143D Version 2 product suite. VJ143C1 is generated daily from all available high-quality reflectance data over a 16-day moving window emphasizing the ninth day of the retrieval period, which is reflected in the Julian date in the filename. VJ143C1 supplies the weighting parameters associated with the RossThick/Li-Sparse-Reciprocal BRDF model that best describes the anisotropy of each pixel, which is used to produce the [VJ143C3](https://doi.org/10.5067/VIIRS/VJ143C3.002) Albedo and [VJ143C4](https://doi.org/10.5067/VIIRS/VJ143C4.002) Nadir BRDF-Adjusted Reflectance (NBAR) products. The highest quality full inversion values are used for the temporal fitting effort and supplemented with lower quality pixels, spatial fitting, and spatial smoothing as needed. The status of each pixel can be found in the ancillary layers. Users are encouraged to assess the quality information before using the BRDF/Albedo data. This 0.05 degree (5,600 meters at the equator) CMG product covers the entire globe for use in climate simulation models. The VJ143C1 product includes 39 layers containing the three parameters (fiso, fvol, and fgeo) for the VIIRS Day/Night band (DNB), moderate resolution bands M1 through M5, M7, M8, M10, and M11, as well as the shortwave band, visible band, and near-infrared (NIR) broadbands. Along with the parameter data for the 13 bands are five ancillary layers for uncertainty, quality, local solar noon, percent finer resolution inputs, and snow cover. A low-resolution browse is also provided showing BRDF/Albedo parameters for bands M5, M4, and M3 as a red, green, blue (RGB) image in JPEG format. 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=VIIRS).

Get the data

vj143c1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ143C1",
    version="002",
    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.