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Full catalog/ATL20
ATL20·v005·dataset

How high sea ice floats, gridded (ICESat-2, daily & monthly)

ATLAS/ICESat-2 L3B Daily and Monthly Gridded Sea Ice Freeboard V005
cryosphere NASA NSIDC_CPRD Level 3 active HDF5
In plain English

What it measures. How high sea ice floats above the surrounding water (its freeboard), summarized on daily and monthly maps.

How it's made. Derived from the ICESat-2 satellite's laser altimeter measurements of along-track ice height, then gridded into daily and monthly averages.

How & where you'd use it. Used to study sea-ice conditions and, with further analysis, to estimate ice thickness — both key for tracking polar change.

What's measured

CRYOSPHERE › SEA ICE › FREEBOARD

Coverage & cadence

  • Time span2018-10-14 → ongoing
  • Measured byICESat-2 (ATLAS)
  • Processing levelLevel 3
  • Spatial extent-180, 37, 180, 89
  • FormatsHDF5
  • 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

ATL20 contains daily and monthly gridded estimates of sea ice freeboard, derived from ATLAS/ICESat-2 L3A Sea Ice Freeboard (ATL10) along-track freeboard estimates.

Get the data

atl20_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ATL20",
    version="005",
    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.