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Full catalog/VJ143IA3
VJ143IA3·v002·dataset

How much sunlight the surface reflects (NOAA-20, daily, 500 m)

VIIRS/JPSS1 BRDF/Albedo Albedo Daily L3 Global 500m SIN Grid V002
land NASA LPCLOUD Level 3 active HDF-EOS5
In plain English

What it measures. How reflective the land surface is at midday (albedo), given both for direct sunlight (black-sky) and even all-directions lighting (white-sky), at 500 m resolution.

How it's made. Produced daily from 16 days of VIIRS data on the NOAA-20 satellite, designed to carry on NASA's long-running MODIS albedo record.

How & where you'd use it. Helps track how much sunlight different surfaces bounce back over time, useful for climate, land-change, and energy-balance research, and for extending the MODIS reflectivity record into the VIIRS era.

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 (VJ143IA3) Version 2 product provides albedo values at 500 meter (m) resolution for the bihemispherical reflectance white-sky albedo (WSA) and directional hemispherical reflectance black-sky albedo (BSA) at local solar noon. The VJ143IA3 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 [VJ143IA1](https://doi.org/10.5067/VIIRS/VJ143IA1.002) to reconstruct surface anisotropic effects, correcting the directional reflectance to a common view geometry ([VJ143IA4](https://doi.org/10.5067/VIIRS/VJ143IA4.002)), while also computing integrated black-sky albedo (BSA) at local solar noon and white-sky albedo (WSA) (VJ143IA3). 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 VJ143IA3 product provides a total of 9 SDS variables including: BSA, WSA, and mandatory quality variables for VIIRS imagery bands I1, I2, and I3. A low-resolution browse image is also available showing retrievals of WSA for band I1 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

vj143ia3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ143IA3",
    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.