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Full catalog/VJ143MA3
VJ143MA3·v002·dataset

How much sunlight the land reflects, daily (VIIRS, NOAA-20, 1 km)

VIIRS/JPSS1 BRDF/Albedo Albedo Daily L3 Global 1km SIN Grid V002
land NASA LPCLOUD Level 3 active HDF-EOS5
In plain English

What it measures. Daily maps of how much sunlight the land surface reflects (its albedo) at 1-kilometer resolution, given both as reflection under direct sun at local noon and under diffuse, all-sky light.

How it's made. Calculated from 16 days of VIIRS observations on the NOAA-20 satellite using a model that accounts for how reflectance changes with viewing and sun angle, then weighted to a central day.

How & where you'd use it. Important for climate and energy-balance studies, since how much sunlight the surface reflects versus absorbs affects warming; it continues NASA's long-running MODIS albedo record.

What's measured

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

Coverage & cadence

  • Time span2018-01-01 → 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 (VJ143MA3) Version 2 product provides albedo values at 1 kilometer (km) resolution for the bihemispherical reflectance white-sky albedo (WSA) and directional hemispherical reflectance black-sky albedo (BSA) at local solar noon. The VJ143MA3 product is produced daily using 16 days of VIIRS data and is weighted temporally to the ninth day, which is reflected in the file name. The VJ143 data products are designed to promote the continuity of NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) BRDF/Albedo data product suite. The VJ143 algorithm uses the RossThick/Li-Sparse-Reciprocal (RTLSR) semi-empirical kernel-driven BRDF model, with the three kernel weights from [VJ143MA1](https://doi.org/10.5067/VIIRS/VJ143MA1.002) to reconstruct surface anisotropic effects, correcting the directional reflectance to a common view geometry ([VJ143MA4](https://doi.org/10.5067/VIIRS/VJ143MA4.002)), while also computing integrated black-sky albedo (BSA) at local solar noon and white-sky albedo (WSA) (VJ143MA3). Researchers can use the BRDF model parameters with a simple polynomial, to obtain black-sky albedo at any solar illumination angle. Likewise, both the BSA and WSA Science Dataset (SDS) variables can be used with a simple polynomial, to manually estimate instantaneous actual albedo (blue-sky albedo). Additional details regarding the methodology are available in the Algorithm Theoretical Basis Document (ATBD). The VJ143MA3 product provides a total of 36 SDS variables including: BSA; WSA; and mandatory quality variables for nine VIIRS moderate bands M1-M5, M7-M8, and M10-M11; as well as near-infrared (NIR); shortwave; and visible broadbands. A low-resolution image is also available showing retrievals of WSA for band M1 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

vj143ma3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ143MA3",
    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.