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Full catalog/VJ202IMG
VJ202IMG·v2.1·dataset

Calibrated raw imagery (NOAA-21, 375 m)

VIIRS/JPSS2 Imagery Resolution 6-Min L1B Swath 375m V2.1
land NASA LAADS Level 1B active netCDF-4
In plain English

What it measures. Calibrated imagery from five sensor bands at 375 m detail, recording both reflected sunlight and heat (infrared) given off by surfaces.

How it's made. Produced from the VIIRS instrument on the NOAA-21 satellite at an early processing stage, converting raw sensor counts into properly calibrated readings.

How & where you'd use it. A foundational input used to build sharper higher-level products, such as fire detection and land and cloud imagery, rather than something most people open directly.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2023-02-10 → ongoing
  • Measured byNOAA-21 (VIIRS)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • 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 VIIRS/JPSS2 Imagery Resolution 6-Min L1B Swath 375m, short-name VJ202IMG is the Joint Polar-orbiting Satellite System-2 (JPSS-2/NOAA-21; referred to hereafter as J2) platform-derived NASA Visible Infrared Imaging Radiometer Suite (VIIRS) L1B calibrated radiances product that comprise five image-resolution or I-bands, which have a 375-meter resolution at nadir. These I-bands comprise three reflective solar bands (RSB) and two thermal emissive bands (TEB). Each of the I-bands has 32 detectors in the along-track direction with 32 rows of pixels per scan that offer a resolution that is twice finer than that of the moderate (M) and Day-Night bands (DNB). Ranging in wavelengths from 0.6 µm to 12.4 µm, the I-bands are sensitive to visible/reflective, near-, shortwave-, mediumwave-, and longwave-infrared wavelengths. The J2 VIIRS radiometric calibration Level-1B reprocessing includes a few calibration updates for the reflective solar bands (RSB), but no significant changes for the day-night band (DNB) or thermal emissive bands (TEB).

Get the data

vj202img_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ202IMG",
    version="2.1",
    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 LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.