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Full catalog/VJ113A2
VJ113A2·v002·dataset

How green the land is (NOAA-20, 16-day, 1 km)

VIIRS/JPSS1 Vegetation Indices 16-Day L3 Global 1km SIN Grid V002
biosphere NASA LPCLOUD Level 3 active HDF-EOS5
In plain English

What it measures. How green and healthy the land vegetation is, summarized as 'vegetation indices' (NDVI and two versions of EVI) that rise with denser, healthier plant cover. It also includes the underlying light-reflectance bands.

How it's made. Made from the VIIRS instrument on the NOAA-20 satellite, choosing the best clear pixel over each 16-day window at 1-km resolution, designed to continue the long MODIS record.

How & where you'd use it. Used to monitor crops, forests, and droughts, and to extend decades-long records of how Earth's vegetation changes over time.

What's measured

BIOSPHERE › VEGETATION › VEGETATION INDEX › NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI)BIOSPHERE › VEGETATION › PLANT PHENOLOGYBIOSPHERE › VEGETATION › VEGETATION INDEX › ENHANCED VEGETATION INDEX (EVI)

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

  • Map vegetation, forests and biomass
  • Monitor ecosystem productivity and carbon
  • Support habitat and biodiversity studies
Official description

The NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Vegetation Indices (VJ113A2) Version 2 data product provides vegetation indices by a process of selecting the best available pixel over a 16-day acquisition period at 1 kilometer (km) resolution. The VJ113 data products are designed after the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua Vegetation Indices product suite to promote the continuity of the Earth Observation System (EOS) mission. The VJ113 algorithm process produces three vegetation indices: The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), and the Enhanced Vegetation Index-2 (EVI2). NDVI is one of the longest continual remotely sensed time series observations, using both the red and near-infrared (NIR) bands. EVI is a slightly different vegetation index that is more sensitive to canopy cover, while NDVI is more sensitive to chlorophyll. EVI2 is a reformation of the standard 3-band EVI, using the red band and NIR band. This reformation addresses arising issues when comparing VIIRS EVI to other EVI models that do not include a blue band. EVI2 will eventually become the standard EVI. Along with the three Vegetation Indices variables, this product also includes variables for NIR reflectance; three shortwave infrared (SWIR) reflectance; red, blue, and green reflectance; composite day of year; pixel reliability; relative azimuth, view, and sun angles, and a quality variable. Two low resolution browse images are also available for each VJ113A2 product: EVI and NDVI. Known Issues * Due to missing critical inputs, this product lacks coverage for tiles h33v07 and h18v14, which are located over water. * 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) and the User Guide and ATBD.

Get the data

vj113a2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ113A2",
    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.