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Full catalog/VJ103MODLL
VJ103MODLL·v021·dataset

Exact pixel locations, a helper file (VIIRS, NOAA-20, 750 m)

VIIRS/JPSS1 Moderate Resolution Terrain Corrected Geolocation 6-Min L1 Swath 750m Light V021
land NASA LPCLOUD Level 1A active HDF-EOS5
In plain English

What it measures. The precise ground location (latitude, longitude, and height) for each pixel in VIIRS data, at 750 meter resolution - essentially a map of where every measurement actually points on Earth.

How it's made. Computed for the NOAA-20 VIIRS sensor by tracing the instrument's line of sight down to Earth's surface using an elevation model, in 6-minute swaths.

How & where you'd use it. A helper file that pairs with other VIIRS products to pin their measurements to the right spot on the ground; most people use it indirectly via those data products.

What's measured

SPECTRAL/ENGINEERING › SENSOR CHARACTERISTICS › GEOLOCATION

Coverage & cadence

  • Time span2018-01-01 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 1A
  • 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 Visible Infrared Imaging Radiometer Suite (VIIRS) Moderate Resolution Terrain Correction Geolocation (VJ103MODLL) Version 2.1 product from the NOAA-20 VIIRS sensor is produced in 6 minute temporal satellite increments (swaths) at 750 meter resolution. Intersecting the VIIRS line of sight vector with Earth’s geoid and the World Geodetic System (WGS) ellipsoid, this product is based on the SRTM30 Version 2 digital elevation model (DEM), which uses GTOPO30 data for areas from 60° North to 60° South. VJ103MODLL is a terrain correction geolocation product that provides the spatial location for various VIIRS data products. Each swath of data is approximately 3,060 kilometers along track (long) and 3,060 kilometers across track (wide). Provided in the VJ103MODLL product are variables for height, latitude, and longitude. These Science Data Sets (SDS) variables are used in conjunction with the ([VJ114](https://doi.org/10.5067/viirs/vj114.002)) swath product for accurate geolocation information. 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

vj103modll_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ103MODLL",
    version="021",
    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.