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Full catalog/GLAH13
GLAH13·v034·dataset

Sea-ice surface heights from laser (ICESat)

GLAS/ICESat L2 Sea Ice Altimetry Data (HDF5) V034
ocean NASA NSIDC_CPRD Level 2 HDF
In plain English

What it measures. The surface height of sea ice, measured by bouncing a laser off the surface, along with the laser footprint's location and reflectance.

How it's made. Produced from the laser altimeter on NASA's ICESat satellite, processed into a Level-2 product specifically for sea-ice regions using algorithms tuned to that surface.

How & where you'd use it. Used to study sea-ice elevation and thickness changes, part of a family of ICESat products covering ice sheets, sea ice, land, and oceans.

What's measured

OCEANS › SEA ICE › ICE ROUGHNESSCRYOSPHERE › SEA ICE › ICE ROUGHNESSCRYOSPHERE › SEA ICE › REFLECTANCECRYOSPHERE › SEA ICE › SEA ICE ELEVATIONOCEANS › SEA ICE › SEA ICE ELEVATION

Coverage & cadence

  • Time span2003-02-20 → 2009-10-11
  • Measured byICESat (ALTIMETERS, CD, GLAS, GPS, GPS Receiver, LA, PC)
  • Processing levelLevel 2
  • Spatial extent-180, -86, 180, 86
  • FormatsHDF
  • StatusCOMPLETE

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

GLAH06 is used in conjunction with GLAH05 to create the Level-2 altimetry products. Level-2 altimetry data provide surface elevations for ice sheets (GLAH12), sea ice (GLAH13), land (GLAH14), and oceans (GLAH15). Data also include the laser footprint geolocation and reflectance, as well as geodetic, instrument, and atmospheric corrections for range measurements. The Level-2 elevation products, are regional products archived at 14 orbits per granule, starting and stopping at the same demarcation (± 50° latitude) as GLAH05 and GLAH06. Each regional product is processed with algorithms specific to that surface type. Surface type masks define which data are written to each of the products. If any data within a given record fall within a specific mask, the entire record is written to the product. Masks can overlap: for example, non-land data in the sea ice region may be written to the sea ice and ocean products. This means that an algorithm may write the same data to more than one Level-2 product. In this case, different algorithms calculate the elevations in their respective products. The surface type masks are versioned and archived at NSIDC, so users can tell which data to expect in each product. Each data granule has an associated browse product.

Get the data

glah13_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GLAH13",
    version="034",
    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.