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Full catalog/SNDRSNCrISL1BIMGC
SNDRSNCrISL1BIMGC·v2·dataset

Index matching infrared and imager pixels (Suomi NPP)

S-NPP CrIS IMG_COL: Array indices for collocated VIIRS observations V2 (SNDRSNCrISL1BIMGC) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. Rather than science data itself, this is a lookup table of array positions that tells you which imager (VIIRS) pixels line up with each infrared sounder (CrIS) measurement.

How it's made. Derived alongside the CrIS infrared sounder data on the Suomi-NPP satellite, computing the matching pixel locations between the CrIS instrument and the VIIRS imager.

How & where you'd use it. A purely technical building block for scientists who need to combine the two instruments' observations; ordinary users encounter its benefits only through higher-level merged products.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › BRIGHTNESS TEMPERATURESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE IMAGERYSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2012-01-20 → ongoing
  • Measured bySuomi-NPP (CrIS, VIIRS)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • 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 Cross-track Infrared Sounder (CrIS) Level 1B Normal Spectral Resolution (NSR) data files contain radiance measurements along with ancillary spacecraft, instrument, and geolocation data of the CrIS instrument on the Suomi National Polar-orbiting Partnership Project (SNPP). In December 2014, the CrIS instrument on the SNPP satellite doubled the spectral resolution of shortwave infrared data being transmitted to the ground. In November 2015, additional points were included at the ends of the longwave and shortwave interferograms to improve the quality of the calibration. Prior to November 2, 2015 the data are only available in Normal Spectral Resolution, after November 2, 2015 at 16:06 UTC, the data are available in both NSR and Full Spectral Resolution (FSR). The NSR files have 1,317 channels: 163 shortwave channels from 3.9 to 4.7 microns (2555 to 2150 cm-1), 437 midwave channels from 5.7 to 8.05 microns (1752.5 to 1242.5 cm-1), and 717 longwave channels from 9.1 to 15.41 microns (1096.25 to 648.75 cm-1). Each CrIS field-of-regard (FOR) contains 9 field-of-views (FOVs) arranged in a 3X3 array. The Level 1B files contain 30 FORs in the cross track direction and 45 in the along track direction. Data products are constructed on six minute boundaries. The Visible Infrared Imaging Radiometer Suite (VIIRS) has 22 imaging and radiometric bands covering wavelengths from 0.41 to 12.5 microns. It provides the sensor data records for clouds, sea surface temperature, ocean color, and others. This IMG_COL product contains the colocation indices of the VIIRS pixels within each CrIS footprint.

Get the data

sndrsncrisl1bimgc_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDRSNCrISL1BIMGC",
    version="2",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.