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Full catalog/VJ143DNBA2
VJ143DNBA2·v002·dataset

How much nighttime light the land reflects (NOAA-20, 1 km daily)

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

What it measures. How much nighttime light the land surface reflects, expressed as albedo and reflectance-shape (BRDF) quality information, at 1 km resolution worldwide.

How it's made. Produced daily from 16 days of Day/Night Band data from the VIIRS instrument on the NOAA-20 satellite, using a model that corrects for viewing angle; designed to continue NASA's earlier MODIS albedo records.

How & where you'd use it. Supports studies of surface reflectivity and continuity with long-running MODIS records; researchers can use its model parameters to compute reflectance under different lighting conditions.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCELAND SURFACE › SURFACE RADIATIVE PROPERTIES › ALBEDOLAND SURFACE › SURFACE RADIATIVE PROPERTIES › ANISOTROPY

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) Day/Night Band (DNB) Bidirectional Reflectance Distribution Function (BRDF) and Albedo Quality (VJ143DNBA2) Version 2 product provides BRDF and Albedo quality at 1 kilometer (km) resolution. The VJ143DNBA2 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 VJ143DNBA2 product gives information regarding band quality and days of valid observation within a 16-day period for the VIIRS DNB. 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 [VJ143DNBA1](https://doi.org/10.5067/VIIRS/VJ143DNBA1.002) to reconstruct surface anisotropic effects, correcting the directional reflectance to a common view geometry ([VJ143DNBA4](https://doi.org/10.5067/VIIRS/VJ143DNBA4.002)), while also computing integrated black-sky albedo (BSA) at local solar noon and white-sky albedo (WSA) ([VJ143DNBA3](https://doi.org/10.5067/VIIRS/VJ143DNBA3.002)). 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 VJ143DNBA2 data product provides a total of seven SDS variables, including BRDF/Albedo band quality and days of valid observation within a 16-day period for the VIIRS DNB, as well as land water type class flag, snow BRDF albedo class flag, local solar noon, and the platform name. 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

vj143dnba2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ143DNBA2",
    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.