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Full catalog/VJ110A1
VJ110A1·v2·dataset

Where snow covers the ground, daily (VIIRS, NOAA-20, 375 m)

VIIRS/JPSS1 Snow Cover Daily L3 Global 375m SIN Grid V002
cryosphere NASA NSIDC_CPRD Level 3 active HDF-EOS5
In plain English

What it measures. A daily worldwide map showing where the ground is covered by snow, at about 375 m detail.

How it's made. Built from light measurements by the VIIRS instrument on the NOAA-20 satellite, combined from many short passes and gridded, using a snow index plus checks to flag uncertain detections.

How & where you'd use it. Valuable for tracking seasonal snow cover, managing water supplies fed by snowmelt, and studying how snow patterns shift with climate.

What's measured

CRYOSPHERE › SNOW/ICE › SNOW COVER

Coverage & cadence

  • Time span2018-01-05 → ongoing
  • Measured byJPSS-1 (VIIRS) · NOAA-20 (VIIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS5
  • StatusACTIVE

What you can do with it

  • Measure sea ice, snow cover and glaciers
  • Watch ice-sheet elevation change
  • Track freeze/thaw and permafrost
Official description

This data set contains daily snow cover derived from radiance data acquired by the Visible Infrared Imaging Radiometer Suite (VIIRS) on board the Joint Polar Satellite System's first satellite (JPSS-1). The data is a gridded composite, generated from 6 minute swaths, and projected to a 375 m Sinusoidal grid. Snow cover is identified using the Normalized Difference Snow Index (NDSI) and a series of screens designed to alleviate errors and flag uncertain snow cover detections.

Get the data

vj110a1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VJ110A1",
    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 NSIDC_CPRD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.