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Full catalog/GLAH01
GLAH01·v033·dataset

Raw laser altimeter readings (ICESat)

GLAS/ICESat L1A Global Altimetry Data (HDF5) V033
land NASA NSIDC_CPRD Level 1A HDF
In plain English

What it measures. The raw laser pulses sent down toward Earth and the echoes bounced back, recorded as full waveforms by the satellite's laser altimeter.

How it's made. Captured directly by the GLAS laser instrument aboard the ICESat satellite at the earliest processing stage, before the signals are turned into elevation measurements.

How & where you'd use it. A raw building-block input most people use via higher-level elevation products rather than directly; specialists work with these waveforms to derive surface heights.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS

Coverage & cadence

  • Time span2003-02-20 → 2009-10-11
  • Measured byICESat (ALTIMETERS, CD, GLAS, GPS Receiver, LA, PC)
  • Processing levelLevel 1A
  • Spatial extent-180, -86, 180, 86
  • FormatsHDF
  • StatusCOMPLETE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

Level-1A altimetry data (GLAH01) include the transmitted and received waveform from the altimeter. Each data granule has an associated browse product.

Get the data

glah01_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GLAH01",
    version="033",
    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.