Earth Data School
About
Full catalog/ATL12
ATL12·v007·dataset

Height of the ocean surface (ICESat-2, v7)

ATLAS/ICESat-2 L3A Ocean Surface Height V007
ocean NASA NSIDC_CPRD Level 3 active HDF5
In plain English

What it measures. The height of the open ocean's surface measured along the satellite's path, including averages, variability, and uncertainty over stretches of sea, even reaching into areas where sea ice is present.

How it's made. Measured by the ATLAS laser altimeter on the ICESat-2 satellite, which times laser pulses bouncing off the sea surface to gauge its height relative to a standard Earth reference shape.

How & where you'd use it. Helps study ocean surface height and its changes, sea state, and conditions near sea ice, contributing to research on ocean circulation and climate.

What's measured

OCEANS › SEA SURFACE TOPOGRAPHY › SEA SURFACE HEIGHT

Coverage & cadence

  • Time span2018-10-13 → ongoing
  • Measured byICESat-2 (ATLAS)
  • Processing levelLevel 3
  • Spatial extent-180, -88, 180, 88
  • FormatsHDF5
  • StatusACTIVE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

ATL12 contains along-track sea surface height (SSH) of the global open ocean relative to the WGS84 ellipsoid. Height averages, distributions, and uncertainties are provided over ocean segments 400 to 7,000 m in length. Heights relative to the EGM2008 geoid and variables such as photon return rate are provided in 10 m along-track bins within each ocean segment. Additionally, 10 m bins corresponding to ATL07 bright leads are identified, and heights within the bins are averaged over ocean segments to yield accurate SSHs where ice concentrations are greater than 15%. The data were acquired by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the ICESat-2 observatory.

Get the data

atl12_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ATL12",
    version="007",
    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.