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Full catalog/VJ117A3GF
VJ117A3GF·v002·dataset

How much carbon plants take in, gap-filled yearly (NOAA-20, 500 m)

VIIRS/JPSS1 Gross and Net Primary Production Gap-Filled Yearly L4 Global 500m SIN Grid V002
atmosphere NASA LPCLOUD Level 4 active HDF-EOS5
In plain English

What it measures. Yearly totals of how much carbon plants take in through photosynthesis (gross primary production) and how much they keep after their own respiration (net primary production), mapped globally at 500-meter detail, with gaps filled.

How it's made. Computed from the VIIRS instrument on the NOAA-20 satellite using a light-use-efficiency approach; poor-quality inputs are cleaned and gaps filled, so it is produced at the end of each year.

How & where you'd use it. Used to estimate annual plant growth and carbon uptake across ecosystems, supporting carbon-cycle and climate research.

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 span2018-01-01 → 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 and Net Primary Production (NPP) Gap-Filled (VJ117A3GF) Version 2 data product is a cumulative composite of Gross Primary Productivity (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. VJ117A3GF is a yearly composite at 500 meter spatial resolution delivered as a gridded Level 4 (L4) product in Sinusoidal projection. The VJ117A3GF will be generated at the end of each year when the entire yearly 8-day VJ115A2H is available. Hence, the gap-filled VJ117A3GF is the improved VJ117A2, which has cleaned the poor-quality inputs from 8-day Leaf Area Index and Fraction of Photosynthetically Active Radiation (LAI/FPAR) based on the Quality Control (QC) label for every pixel. If any LAI/FPAR pixel did not meet the quality screening criteria, its value is determined through linear interpolation. However, users cannot get VJ117A3GF in near-real time because it will be generated only at the end of a given year. Provided in the VJ117A3GF product are variables for GPP, NPP, along with a quality control variable. A low resolution browse image for GPP is also available for each VJ117A3GF 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

vj117a3gf_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ117A3GF",
    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.