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Full catalog/GLAH12
GLAH12·v034·dataset

Ice sheet surface height by laser (ICESat, Antarctica and Greenland)

GLAS/ICESat L2 Global Antarctic and Greenland Ice Sheet Altimetry Data (HDF5) V034
hydrosphere NASA NSIDC_CPRD Level 2 HDF
In plain English

What it measures. The surface height (elevation) of the Antarctic and Greenland ice sheets, along with the exact location and reflectance of each laser spot and the corrections applied to the measurements.

How it's made. Produced from the GLAS laser altimeter aboard ICESat, which times laser pulses bouncing off the ice; this is a Level-2 elevation product covering ice-sheet regions.

How & where you'd use it. Used to map ice-sheet surfaces and, over time, to detect whether the ice is thickening or thinning.

What's measured

TERRESTRIAL HYDROSPHERE › GLACIERS/ICE SHEETS › GLACIER ELEVATION/ICE SHEET ELEVATIONCRYOSPHERE › GLACIERS/ICE SHEETS › GLACIER TOPOGRAPHY/ICE SHEET TOPOGRAPHYCRYOSPHERE › GLACIERS/ICE SHEETS › ICE SHEETSCRYOSPHERE › SEA ICE › REFLECTANCE

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

  • Follow rainfall, floods and surface-water extent
  • Track soil moisture and the onset of drought
  • Monitor lakes, rivers and groundwater storage
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

glah12_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GLAH12",
    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.