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Full catalog/SNPPCrISL1B
SNPPCrISL1B·v3·dataset

Raw infrared spectra of the atmosphere (Suomi-NPP CrIS)

Suomi NPP CrIS Level 1B Full Spectral Resolution V3 (SNPPCrISL1B) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. Highly detailed infrared 'fingerprints' of the atmosphere across more than 2,200 wavelength channels, recording how much infrared energy reaches the sensor. These raw spectra carry information about temperature and gases in the air.

How it's made. Captured by the CrIS infrared sounder on the Suomi-NPP satellite and calibrated to engineering-quality readings; this Version 3 improves the calibration and geolocation.

How & where you'd use it. A foundational input most people use indirectly: scientists turn these spectra into temperature, moisture, and gas profiles for weather forecasting and atmospheric studies.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › BRIGHTNESS TEMPERATURESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCE

Coverage & cadence

  • Time span2015-11-02 → ongoing
  • Measured bySuomi-NPP (CrIS)
  • 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 Suomi National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory 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 (NSR), after November 2, 2015 at 16:06 UTC, the data are available in both NSR and Full Spectral Resolution. The FSR files have 2,223 channels: 637 shortwave channels from 3.9 to 4.7 microns (2555 to 2150 cm-1), 869 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. Version 3 of this product contain improvements to the L1B calibration, geolocation, quality monitoring, and metadata. Additional information can be found in the NASA Cross Track Infrared Sounder (CrIS) Level 1B Product Users’ Guide. CrIS is designed to be used with the ATMS (Advanced Technology Microwave Sounder) instrument. Processing the data from both of these instruments together is referred to as CrIMSS (Cross-Track Infrared and Microwave Sounder Suite). If you were redirected to this page from a DOI from an older version, the "Version History" tab will provide additional information about older versions of this product. Please contact the GES DISC user support if you need additional information.

Get the data

snppcrisl1b_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNPPCrISL1B",
    version="3",
    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.