NASA’s Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is the next-generation orbiting laser altimeter. Its primary aim is to monitor sea-ice thickness and ice sheet elevation change at scales from outlet glaciers to the entire ice sheet, and enable global assessment of biomass. While the fundamental measurement of any lidar is range to a target, several geophysical techniques must be brought to bear to apply altimetry data to geophysical problems. For example, using measurements of elevation change (requiring a number of geometric and statistic techniques to derive elevation change from individual elevation measurements) of the ice sheets in order to estimate mass change requires consideration of firn compaction (a non-linear, non-steady process that is strongly coupled to temperature and snowfall), post-glacial rebound, forward scattering in the atmosphere and the potential for complex interaction between the transmitted laser pulse and the medium of interest.
ICESat-2 will carry the Advanced Topographic Laser Altimeter System (ATLAS) and collect data to a latitudinal limit of 88 degrees. In contrast to the main instrument on ICESat, ATLAS employs a 6-beam micro-pulse laser photon-counting approach. It uses a high repetition rate (10 kHz; resulting in 70 cm footprint spacing on the ground along the direction of travel) low-power laser in conjunction with single-photon sensitive detectors to measure ranges using 532 nm (green) laser light. ICESat-2 is now in Phase C (Design and Development), and is scheduled to launch in mid-2017. My role in the mission as the Deputy Project Scientist is to insure that the science objectives of the mission are met, lead data product development, and maintain a working knowledge of the instrument, ground system, and spacecraft. I also serve as a bridge between the ICESat-2 science team, the wider community of altimetry scientists, and the ICESat-2 mission. I will present an overview of the mission, and discuss the core science objectives of the mission as well as other potential uses of ICESat-2 data, and highlight connections between space-borne laser altimetry and a range of geophysical applications.