ATLAS/ICESat-2 L2A Global Geolocated Photon Data, Version 3
Data set id:
ATL03
DOI: 10.5067/ATLAS/ATL03.003
There is a more recent version of these data.
Version Summary
Version Summary
Changes for this version include:
- Added a QA parameter that indicates the percent of reference photons within a certain distance from the reference DEM (at the geolocation segment rate). The threshold difference for each possible confidence level of reference photons is: 50 m for high confidence; 100 m for medium confidence; 200 m for low confidence; and 200 m for buffer/noise-level reference photons.
- Fixed a logic error in the code that combines the POD and PPD degrade values. In conjunction with this fix, the definition of the podppd_flag parameter was changed to simply indicate if POD, PPD, or both report, in general, a degraded geolocation solution. The previous approach was deemed overly complex for users.
- Effectively removed from consideration by the signal classification processing any photons from telemetry bands that do not intersect the DEM height within a +/- 30 m buffer. Additionally, photons that are poorly geolocated (as indicated by the podppd_flag) are no longer classified as potential signal.
- Created two new parameters (/gtx/geolocation/near_sat_frac and /gtx/geolocation/full_sat_frac) that indicate nearly or fully saturated ATLAS shots. These parameters report the percentage of observed shots that are nearly or fully saturated within a geolocation segment.
Overview
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.
Parameter(s):
TERRAIN ELEVATION
Platform(s):
ICESat-2
Sensor(s):
ATLAS
Data Format(s):
HDF5
Temporal Coverage:
13 October 2018 to 11 November 2020
Temporal Resolution:
- 91 day
Spatial Resolution:
- 70 cm
- 70 cm
Spatial Reference System(s):
WGS 84
EPSG:4326
Spatial Coverage:
N:
90
S:
-90
E:
180
W:
-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
Data Access & Tools
This data set has been retired. There is a more recent version of these data.
Documentation
User Guide
ATBDs
General Resources
Product Specification Documents
Help Articles
General Questions & FAQs
This article covers frequently asked questions about the NASA NSIDC DAAC's Earthdata cloud migration project and what it means to data users.
This short article describes the customization services available for ICESat-2 data using Earthdata Search.
How to Articles
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.Users have the option to
Harmony API Quickstart Guide: Customizing NASA NSIDC DAAC data in Earthdata Cloud
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.
Learn the basic steps for using OpenAltimetry to browse and download ICESat-2 data products.
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).
The NASA Earthdata Cloud is the NASA cloud-based archive of Earth observations. It is hosted by Amazon Web Services (AWS). Learn how to find and access NSIDC DAAC data directly in the cloud.
All data from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC) is directly accessible through our HTTPS file system using Wget or curl. This article provides basic command line instructions for accessing data using this method.
This article highlights the NSIDC DAAC data sets available with customization options and outlines a workflow for searching, ordering, and customizing data in NASA Earthdata Search. This approach is ideal for users who want to download data to their local machine.
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.