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Full catalog/RDEFT4
RDEFT4·v1·dataset

How thick the sea ice is (CryoSat-2)

CryoSat-2 Level-4 Sea Ice Elevation, Freeboard, and Thickness V001
cryosphere NASA NSIDC_CPRD Level 4 active PNGnetCDF-3
In plain English

What it measures. Estimates of Arctic sea ice thickness and how much of the ocean it covers, plus how high the ice rides above the water (freeboard), surface roughness, and snow depth and density on top.

How it's made. Derived from the radar altimeter on ESA's CryoSat-2 satellite, with snow and ice data combined and delivered daily on a 25 km grid as 30-day averages for September through May.

How & where you'd use it. Used to monitor how thick Arctic sea ice is and how it is changing, important for tracking polar climate and the long-term health of the ice pack.

What's measured

CRYOSPHERE › SEA ICE › FREEBOARDCRYOSPHERE › SEA ICE › ICE DEPTH/THICKNESSCRYOSPHERE › SEA ICE › ICE ROUGHNESSCRYOSPHERE › SEA ICE › SEA ICE CONCENTRATIONCRYOSPHERE › SNOW/ICE › SNOW DENSITYCRYOSPHERE › SNOW/ICE › SNOW DEPTH

Coverage & cadence

  • Time span2010-09-20 → ongoing
  • Measured byCRYOSAT-2 (SIRAL) · DMSP 5D-3/F17 (SSMIS)
  • Processing levelLevel 4
  • Spatial extent-180, 55, 180, 90
  • FormatsPNG, netCDF-3
  • 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 estimates of Arctic sea ice thickness and concentration, ice freeboard and surface roughness, as well as snow density and depth, derived from the ESA CryoSat-2 Synthetic Aperture Interferometric Radar Altimeter (SIRAL). The data are provided daily on a 25 km grid as 30-day averages for the months between September and May.

Get the data

rdeft4_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="RDEFT4",
    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 NSIDC_CPRD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.