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ATLAS/ICESat-2 L3A Sea Ice Height, Version 5 (ATL07)
Data set:
ATL07
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This is the most recent version of these data.
Version Summary
Changes for this version include:

  • The ATL07 QA check (atl07_qa_mod) for insufficient output failure has been updated to only check for valid sea ice segments. Previously, total number of sea ice segments written (valid and invalid) were counted.

  • The description of height_segment_confidence was updated so that it agrees with the coded procedure.

  • A max_incidence_angle filter was implemented and added as a controllable override. If the beam incidence angle exceeds max_incidence_angle, the surface type will be set to -1.

  • A contrast filter has been implemented, but turned off by default. Two new controllable parameters have been added.

  • The podppd flag has been added to the ATL07 product and is used to filter heights and segment surface type.

  • A new parameter height_segment_n_pulse_seg_used has been added to the ATL07 product. This parameter excludes the number of specular returns filtered out of processing, unlike height_segment_n_pulse_seg.

  • The description of photon_rate has been updated so that it is clear how the parameter is computed.

  • Modified the integration test scripts to generate browse products and check for the presence of default1 and default2 plots.

  • Updated the ANC31 sea ice concentration interface to read either v1 or v2 of the sea ice concentration files.

  • New parameters of mean ocean sea level pressure and dynamic inverted barometer effect are calculated in ATL07. These are not currently applied to the heights but could be in future releases. The new parameters are: /ancillary_data/sea_ice /mean_ocean_slp: Mean ocean sea level pressure computed in ATL07 and /gtx/sea_ice_segments/geophysical/height_segment_dynib: Dynamic inverted barometer.

Overview

The data set (ATL07) contains along-track heights for sea ice and open water leads (at varying length scales) relative to the WGS84 ellipsoid (ITRF2014 reference frame) after adjustment for geoidal and tidal variations, and inverted barometer effects. Height statistics and apparent reflectance are also provided. The data were acquired by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board the Ice, Cloud and land Elevation Satellite-2 (ICESat-2) observatory.
Data Contributor(s):
  • Ron
    Kwok
  • Alek
    Petty
  • Glenn
    Cunningham
  • Thorsten
    Markus
  • David
    Hancock
  • Alvaro
    Ivanoff
  • Jesse
    Wimert
  • Marco
    Bagnardi
  • Nathan
    Kurtz
Parameter(s):
SEA ICE ELEVATION
Platform(s):
ICESat-2
Sensor(s):
ATLAS
Data Format(s):
HDF5
Temporal Coverage:
14 October 2018 to present
Temporal Resolution:
91 day
Spatial Resolution:
Varies
Spatial Coverage:
N:
90
S:
-90
E:
180
W:
-180

Data Access & Tools

A free NASA Earthdata Login account is required to access these data. Learn More

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 data set web pages provide the ability to search and filter data with spatial and temporal contstraints using a map-based interface. This article outlines how to order NSIDC DAAC data using advanced searching and filtering. 
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).
  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 or through our Application Programming Interface (API).
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.
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