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Full catalog/ATL04
ATL04·v007·dataset

Laser bounce-back showing clouds and air haze (ICESat-2)

ATLAS/ICESat-2 L2A Normalized Relative Backscatter Profiles V007
land NASA NSIDC_CPRD Level 2A active HDF5
In plain English

What it measures. Profiles of how strongly laser light bounces back from the atmosphere at different heights, which reveals clouds and airborne haze layers in a vertical slice beneath the satellite.

How it's made. Acquired by the ATLAS laser instrument on NASA's ICESat-2 satellite, recorded as uncalibrated backscatter many times per second, with calibration coefficients included.

How & where you'd use it. Useful for studying clouds and aerosol layers and, since this is a lower-level radiometric product, mainly serves as an input for higher-level atmospheric analyses.

What's measured

SPECTRAL/ENGINEERING › LIDAR › LIDAR BACKSCATTER

Coverage & cadence

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

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

ATL04 contains along-track normalized relative backscatter (NRB) profiles of the atmosphere. The product includes full 532 nm (14 km tall) uncalibrated attenuated backscatter profiles at 25 times per second for vertical bins of approximately 30 meters. Calibration coefficient values derived from data between 13.5 and 11 km above the surface are also included. The data were acquired by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the ICESat-2 observatory.

Get the data

atl04_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ATL04",
    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.