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Full catalog/SNDRSNIML2CCPCCRN
SNDRSNIML2CCPCCRN·v2·dataset

Infrared readings with clouds removed (Suomi-NPP)

Sounder SIPS: Suomi NPP CrIMSS Level 2 CLIMCAPS Normal Spectral Resolution: Cloud Cleared Radiances V2 (SNDRSNIML2CCPCCRN) at GES DISC
land NASA GES_DISC Level 2 active
In plain English

What it measures. Infrared readings across 1,305 channels with the effects of clouds mathematically removed, representing what the sensor would have seen if the sky had been completely clear.

How it's made. Produced by the CLIMCAPS algorithm using the CrIS infrared sounder paired with the ATMS microwave sounder on the Suomi-NPP satellite, which together estimate and subtract the cloud contribution.

How & where you'd use it. An intermediate input that feeds retrievals of temperature, humidity, and atmospheric composition; most people use it through those higher-level products rather than directly.

What's measured

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

Coverage & cadence

  • Time span2012-01-20 → ongoing
  • Measured bySuomi-NPP (CrIS, ATMS)
  • Processing levelLevel 2
  • 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 CLIMCAPS (Community Long-term Infrared Microwave Coupled Product System) algorithm is used to analyze data from the Cross-track Infrared Sounder/Advanced Technology Microwave Sounder (CrIS/ATMS) instruments, also known as CrIMSS (Cross-track Infrared and Microwave Sounding Suite). The CrIS/ATMS instruments used for this product are on board the Suomi National Polar-orbiting Partnership (SNPP) platform and use the Normal Spectral Resolution (NSR) data. The CrIS instrument is a Fourier transform spectrometer with a total of 1305 NSR infrared sounding channels covering the longwave (655-1095 cm-1), midwave (1210-1750 cm-1), and shortwave (2155-2550 cm-1) spectral regions. The ATMS instrument is a cross-track scanner with 22 channels in spectral bands from 23 GHz through 183 GHz. Cloud clearing is the process of computing the clear column radiance for a given channel n, and represents what the channel would have observed if the entire scene were cloud free. The entire scene is defined as the ATMS field of regard (FOR) which includes and array of 3x3 CrIS field of views (FOV). The basic assumption of cloud-clearing is that if the observed radiances in each field-of-view are different, the differences in the observed radiances are solely attributed to the differences in the fractional cloudiness in each field of view while everything else (surface properties and atmospheric state) is uniform across the field of regard. A level 2 granule has been set as 6 minutes of data, 30 footprints cross track by 45 lines along track. There are 240 granules per day, with an orbit repeat cycle of approximately 16 day. The CLIMCAPS algorithm uses data from the second Modern-Era Retrospective analysis for Research and Applications (MERRA-2) as a first-guess for the atmospheric state. Because MERRA-2 products typically have a latency from 3 to 7 weeks, so too do the CLIMCAPS products.

Get the data

sndrsniml2ccpccrn_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDRSNIML2CCPCCRN",
    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.