The Ice, Cloud, and Land Elevation Satellite – 2 mission: A global geolocated photon product derived from the Advanced Topographic Laser Altimeter System

• Published in: Remote sensing of environment Vol. 233; p. 111325
• Main Authors: Neumann, Thomas A., Martino, Anthony J., Markus, Thorsten, Bae, Sungkoo, Bock, Megan R., Brenner, Anita C., Brunt, Kelly M., Cavanaugh, John, Fernandes, Stanley T., Hancock, David W., Harbeck, Kaitlin, Lee, Jeffrey, Kurtz, Nathan T., Luers, Philip J., Luthcke, Scott B., Magruder, Lori, Pennington, Teresa A., Ramos-Izquierdo, Luis, Rebold, Timothy, Skoog, Jonah, Thomas, Taylor C.
• Format: Journal Article
• Language: English
• Published: Goddard Space Flight Center Elsevier Inc 01-11-2019; Elsevier; Elsevier BV
• Subjects: Altimeters; Altimetry; Body height; Cryosphere; Earth Resources And Remote Sensing; Elevation; Freeboard; Glacier size; Glaciers; Global positioning systems; GPS; Ice; Ice sheets; ICESat-2; Inertial platforms; Inland waters; Laser altimeter; Laser altimeters; Lasers; Observatories; Ocean surface; Photon counting; Photons; Remote sensing; Satellite observation; Satellites; Sea ice; Star trackers; Topography; Water bodies; Photon counting; ICESat-2; Laser altimeter; Ice sheets; Altimetry; Remote sensing; Cryosphere; Sea ice; Icesat-2
• ISSN: 0034-4257; 1879-0704
• DOI: 10.1016/j.rse.2019.111325

The Ice, Cloud, and land Elevation Satellite – 2 (ICESat-2) observatory was launched on 15 September 2018 to measure ice sheet and glacier elevation change, sea ice freeboard, and enable the determination of the heights of Earth's forests. ICESat-2's laser altimeter, the Advanced Topographic Laser Altimeter System (ATLAS) uses green (532 nm) laser light and single-photon sensitive detection to measure time of flight and subsequently surface height along each of its six beams. In this paper, we describe the major components of ATLAS, including the transmitter, the receiver and the components of the timing system. We present the major components of the ICESat-2 observatory, including the Global Positioning System, star trackers and inertial measurement unit. The ICESat-2 Level 1B data product (ATL02) provides the precise photon round-trip time of flight, among other data. The ICESat-2 Level 2A data product (ATL03) combines the photon times of flight with the observatory position and attitude to determine the geodetic location (i.e. the latitude, longitude and height) of the ground bounce point of photons detected by ATLAS. The ATL03 data product is used by higher-level (Level 3A) surface-specific data products to determine glacier and ice sheet height, sea ice freeboard, vegetation canopy height, ocean surface topography, and inland water body height.
•Describes the ICESat-2 Observatory and its sole instrument: the Advanced Topographic Laser Altimeter System (ATLAS)•Presents the structure and major contents of the ICESat-2 Level 1B data product (ATL02; photon times of flight)•Presents the structure and major contents of the ICESat-2 Level 2A data product (ATL03; Global Geolocated Photons)