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Full catalog/CLDCR_L2_VIIRS_SNPP
CLDCR_L2_VIIRS_SNPP·v1·dataset

How much thin cirrus cloud is overhead (VIIRS, Suomi-NPP)

VIIRS/SNPP Cirrus Reflectance 6-min L2 Swath 750m
land NASA LAADS Level 2 active NetCDF-4
In plain English

What it measures. This indicates the presence of thin, high cirrus cloud and how confident the algorithm is that the ground was seen clearly, also flagging where shadows affect the scene. It is essentially a clear-view confidence map.

How it's made. Produced from the VIIRS sensor on Suomi-NPP at 750-meter detail, using a series of visible and infrared tests on the sensor's measured light; gaps appear wherever the input data was missing or low quality.

How & where you'd use it. Mainly a quality and screening input that helps other products tell clear scenes from cloudy ones, rather than a product most people view on its own.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2012-03-01 → ongoing
  • Measured bySuomi-NPP (VIIRS)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsNetCDF-4
  • 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 VIIRS/Suomi-NPP Cirrus Reflectance 6-Min Swath 750m product is a Level-2 product generated at 750-m (at nadir) spatial resolutions. The algorithm employs a series of visible and infrared threshold and consistency tests to specify confidence that an unobstructed view of the Earth's surface has been observed. An indication of shadows affecting the scene is also provided. Radiometrically-accurate radiances are required, thus holes in the Cloud Mask will appear wherever the input radiances are incomplete or of poor quality assurance. For more information consult Product Page at: https://cimss.ssec.wisc.edu/MVCM/

Get the data

cldcr_l2_viirs_snpp_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="CLDCR_L2_VIIRS_SNPP",
    version="1",
    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 LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.