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Full catalog/SNDRSNCrISL1BIMG
SNDRSNCrISL1BIMG·v2·dataset

Cloud-mask summary linking two Suomi-NPP instruments

S-NPP CrIS IMG: Collocated VIIRS level 1 / cloud mask statistical summary V2 (SNDRSNCrISL1BIMG) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. A statistical summary linking detailed imaging and cloud-mask data from one instrument to the footprints of an infrared sounder on the same satellite.

How it's made. Produced by matching the CrIS infrared sounder with the higher-resolution VIIRS imager aboard the Suomi-NPP satellite, grouping VIIRS values into each CrIS field of view.

How & where you'd use it. A companion product to the CrIS radiance data, used by researchers to account for cloud conditions within each sounding when analyzing the atmosphere.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › BRIGHTNESS TEMPERATURESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE FLUX

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 product primarily contains statistics of the VIIRS cloud mask and VIIRS L1B data within each CrIS footprint..

Get the data

sndrsncrisl1bimg_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDRSNCrISL1BIMG",
    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.