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Full catalog/SNDRJ2CrISL1BIMG
SNDRJ2CrISL1BIMG·v3.0·dataset

Cloud-mask summary linking two JPSS-2 instruments

JPSS-2 CrIS IMG: Collocated VIIRS level 1 / cloud mask statistical summary V3.0 (SNDRJ2CrISL1BIMG) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. A statistical summary that matches detailed cloud and imaging information from one instrument to the footprints of another, both on the same satellite, including cloud-mask values.

How it's made. Created by pairing data from the CrIS infrared sounder with the higher-resolution VIIRS imager aboard the JPSS-2 (NOAA-21) satellite, aggregating VIIRS values within each CrIS view.

How & where you'd use it. Designed to be used alongside the CrIS measurements, mainly by atmospheric scientists who need to know cloud conditions within each sounding footprint.

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 span2023-02-22 → ongoing
  • Measured byNOAA-21 (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 Full Spectral Resolution (FSR) data files contain radiance measurements along with ancillary spacecraft, instrument, and geolocation data of the CrIS instrument on the Joint Polar Satellite System-2 (JPSS-2) platform. This platform is also know as NOAA-21 (National Oceanic and Atmospheric Administration). The IMG product supplements the CrIS Level 1B (L1B) hyperspectral radiance product by providing collocated high-spatial resolution data from the Visible Infrared Imaging Radiometer Suite (VIIRS) imager located on the same platform. VIIRS radiance and cloud mask values are grouped and aggregated for every CrIS field of view (FOV) and made available in a format intended for use alongside the CrIS L1B data. The collocated VIIRS level 1 / cloud mask statistical summary is the main product and consists of collocated CrIS field of views with the VIIRS cloud mask and radiances/reflectances. This can be thought of as a match-up between CrIS and VIIRS. The supplementary product, array indices for collocated VIIRS observations (collection name SNDRJ2CrISL1BIMGC), consists of array indices for collocated VIIRS observations and provides the collocated indices of the VIIRS pixels within each CrIS footprint. The FSR files have 2,223 channels (*2211 apodized channels): 637 (*633) shortwave channels from 3.9 to 4.7 microns (2555 to 2150 cm-1), 869 (*865) midwave channels from 5.7 to 8.05 microns (1752.5 to 1242.5 cm-1), and 717 (*713)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

sndrj2crisl1bimg_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDRJ2CrISL1BIMG",
    version="3.0",
    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.