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Full catalog/VJ117A2
VJ117A2·v002·dataset

How much carbon plants capture, 8-day (NOAA-20, 500 m)

VIIRS/JPSS1 Gross Primary Productivity and Net Photosynthesis 8-Day L4 Global 500m SIN Grid V002
atmosphere NASA LPCLOUD Level 4 active HDF-EOS5
In plain English

What it measures. Estimates how much carbon plants pull from the air through photosynthesis (gross primary productivity) and their net photosynthesis, summed over 8-day windows across the globe at 500 m detail.

How it's made. Calculated from the VIIRS instrument on the NOAA-20 satellite using the radiation-use-efficiency approach, delivered as a gridded product.

How & where you'd use it. Feeds models of the carbon, water, and energy cycles and helps scientists track how productive and healthy vegetation is worldwide.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROCESSES › EVAPOTRANSPIRATIONATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROCESSES › EVAPORATIONATMOSPHERE › PRECIPITATION › PRECIPITATION PROFILES › LATENT HEAT FLUXBIOSPHERE › VEGETATION › VEGETATION PRODUCTIVITY

Coverage & cadence

  • Time span2025-01-01 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 4
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS5
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Gross Primary Productivity (GPP) and Net Photosynthesis (PSN) (VJ117A2) Version 2 data product is a cumulative composite of GPP values based on the radiation use efficiency concept that is potentially used as inputs to data models to calculate terrestrial energy, carbon, water cycle processes, and biogeochemistry of vegetation. VJ117A2 is an 8-day composite at 500 meter spatial resolution delivered as a gridded Level 4 (L4) product in Sinusoidal projection. Provided in the VJ117A2 product are layers for GPP, PSN, along with a quality control layer. A low resolution browse image for GPP is also available for each VJ117A2 granule. 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

vj117a2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ117A2",
    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.