• For a list of known issues with this product, see the Known Issues document under the Documentation section of the page.

ATLAS/ICESat-2 L2A Global Geolocated Photon Data, Version 4 (ATL03)
Data set:
There is a more recent version of these data.
Version Summary
Changes for this version include:

  • Added a per-photon indicator of possible saturated conditions and/or instrument related effects (quality_ph) allowing users to easily identify photons that are not likely true surface due to saturation conditions and/or internal reflections within the ATLAS instrument.

  • Improved the saturation fraction computations for near_sat_frac and full_sat_frac to accommodate the quality_ph calculation.

  • Added roll, pitch and yaw from the ANC04 POD file and interpolated them to the geolocation segment rate. These parameters provide the users the components necessary to determine spacecraft orientation and altitude that may influence relative distance between the beams.

  • Replaced GMDED2010 with the 3 arc-second MERIT DEM as the global DEM. ATL03 uses reference DEMs to exclude photons outside of the primary telemetry band from signal classification to reduce the number of clouds inadvertently classified as signal. The 3 arc-second spatial resolution of the MERIT DEM is an improvement over the 7.5 arc-second resolution of GMTED2010 providing better terrain heights, particularly over forested regions and river basins.

  • Changed geoid from EGM2008 mean-tide system to EGM2008 tide-free system. This allows users more easily to re-reference photon heights above the geoid without additional corrections, bringing consistency to the tidal systems on ATL03.

  • Added conversion factors for geoid and solid earth tide that allow easy conversion from/to tide-free/mean-tide systems allowing users to flexibly convert between the tide systems.


This data set (ATL03) contains height above the WGS 84 ellipsoid (ITRF2014 reference frame), latitude, longitude, and time for all photons downlinked by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the Ice, Cloud and land Elevation Satellite-2 (ICESat-2) observatory. The ATL03 product was designed to be a single source for all photon data and ancillary information needed by higher-level ATLAS/ICESat-2 products. As such, it also includes spacecraft and instrument parameters and ancillary data not explicitly required for ATL03.
Data Contributor(s):
  • Thomas
  • Anita
  • David
  • John
  • Jack
  • Kaitlin
  • Aimée
  • Jeff
  • Scott
Data Format(s):
Temporal Coverage:
13 October 2018 to 15 July 2021
Temporal Resolution:
91 day
Spatial Resolution:
70 cm
70 cm
Spatial Coverage:

Data Access & Tools

This data set has been retired. There is a more recent version of these data.

Help Articles

How To

This webinar introduces the ICESat-2 mission and shows you how to explore, access and customize ICESat-2 data with the OpenAltimetry application, using NSIDC DAAC tools, and shows you how to subset, reformat and analyze the data using Python.
Many NSIDC DAAC data sets can be accessed using the NSIDC DAAC's Data Access Tool. This tool provides the ability to search and filter data with spatial and temporal constraints using a map-based interface.
To convert HDF5 files into binary format you will need to use the h5dump utility, which is part of the HDF5 distribution available from the HDF Group. How you install HDF5 depends on your operating system.
This guide will provide an overview of the altimetry measurements and data sets across the missions, as well as a guide for accessing the data through NASA Earthdata Search and programmatically using an Application Programming Interface (API).
All data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) can be accessed directly from our HTTPS file system, using wget or curl. Basic command line instructions are provided in the article below. 
NASA Earthdata Search is a map-based interface where a user can search for Earth science data, filter results based on spatial and temporal constraints, and order data with customizations including re-formatting, re-projecting, and spatial and parameter subsetting.

Getting started

The following table describes the subsetting and reformatting services that are currently available for ICESat-2 data via the NASA Earthdata Search tool, along with