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Full catalog/NSIDC-0778
NSIDC-0778·v1·dataset

Where Antarctic ice starts floating (grounding zone)

MEaSUREs Grounding Zone of the Antarctic Ice Sheet V001
cryosphere NASA NSIDC_CPRD Level 4 ShapefileGeoPackage
In plain English

What it measures. Maps the narrow zone around Antarctica where the ice sheet stops resting on bedrock and starts floating on the ocean, and shows how that boundary shifts back and forth with the ocean tides over a year.

How it's made. Created by an automated machine-learning method that traces the boundary in radar images from Sentinel-1 satellites, with help from COSMO-SkyMed, RADARSAT, and ERS satellites.

How & where you'd use it. Helps scientists watch where Antarctic ice is most vulnerable to ocean melting and track changes that signal ice-sheet instability and future sea-level rise.

What's measured

CRYOSPHERE › GLACIERS/ICE SHEETS › GLACIERS › GROUNDING LINE

Coverage & cadence

  • Time span2018-01-01 → 2020-12-31
  • Measured byCOSMO-SKYMED (SAR) · ERS-1 (SAR) · ERS-2 (SAR) · RADARSAT-1 (SAR) · RADARSAT-2 (SAR) · Sentinel-1A (C-SAR) · Sentinel-1B (C-SAR)
  • Processing levelLevel 4
  • Spatial extent-180, -90, 180, -60
  • FormatsShapefile, GeoPackage
  • StatusCOMPLETE

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 provides a comprehensive map for the Antarctic Ice Sheet of the short-term zone of migration of the ice grounding line (i.e., the transition boundary between grounded ice and ice floating in the ocean waters) for the given period, due to changes in oceanic tide. This variation is represented by polylines that indicate the upstream and downstream bounds in the grounding line variation for a given year. The data are derived using an automated machine learning algorithm to delineate thousands of grounding lines in interferometric synthetic aperture radar (InSAR) data acquired by Sentinel-1 A/B, supplemented by data from COSMO SkyMed, RADARSAT-2, and European Remote Sensing (ERS) satellites.

Get the data

nsidc-0778_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="NSIDC-0778",
    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.