Abstract
Abstract. Digital elevation models (DEMs) are of fundamental importance for a large variety of scientific and commercial applications. Many geoscience studies require the most precise and current information about the Earth’s topography. Independent quality assessments of these DEMs are crucial to their appropriate use in land process studies, as inputs to models, and for detection of topographic change. The Ice, Cloud and land Elevation Satellite (ICESat) provided globally-distributed elevation data of high accuracy that demonstrated to be well-suited for evaluating continental DEMs after appropriate editing (Carabajal and Harding, 2005; Carabajal and Harding, 2006; Carabajal et al., 2010 and 2011; Carabajal and Boy, 2016). ICESat-2, launched on September 15th, 2018, provides an opportunity to develop a dataset suitable for Geodetic Ground Control. With increased coverage, ICESat-2/ATLAS features 6 laser beams with 532 nm wavelength, using photon counting technologies. With a nearly polar orbit, altimetry from ICESat-2 is available for latitudes reaching up to 88 degrees, on a 91-day repeat orbit with monthly sub-cycles. ICESat-2’s footprint size is ∼17 m, at 10 kHz pulse repetition frequency, or 0.75 m along track. Its pointing control is 45 m, with a pointing knowledge of 6.5 m, and a single photon precision of 800 ps. Sophisticated data processing techniques on the ground, optimized by surface type, produce high quality estimates of topography. We illustrate the use of ICESat-2 altimetry to assess DEM’s accuracy using ATL08 release 002 elevations (Land and Vegetation) products (Neuenschwander and Pitts, 2019), showing comparable results to those using ICESat-derived Geodetic Ground Control.
Highlights
1.1 ICESat-2 Mission and the Advanced Topographic Laser Altimeter System (ATLAS) InstrumentThe Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) mission (Markus et al, 2017; Neuman et al, 2019b) is the successor to the ICESat mission (Zwally et al, 2002; Schutz et al, 2005)
The development of this database is documented in Carabajal et al (2010 and 2011), and the data include laser returns that satisfy high accuracy elevation requirements. Their accuracy estimates have been supported by accuracy estimates from rigorous analysis of instrument calibration and validation schemes using ocean scan maneuvers and cross-overs (Carabajal et al, 2011). This high quality laser altimetry estimates of land elevations have been used in many validation studies to evaluate the quality of Digital Elevation Models (DEMs) like those produced by the Shuttle Radar Topography Mission (SRTM) mission (Farr and Kobrick, 2000), described in Carabajal and Harding (2005 and 2006) and Carabajal et al (2010), evaluations of GMTED2010 (Danielson & Gesch, 2011) described in Carabajal et al (2011), and as part of the validation efforts for various versions of ASTER GDEM, shown for ASTER GDEM V3 (NASA/METI/AIST/Japan Spacesystems, and U.S./Japan ASTER Science Team, 2019) as in Carabajal and Boy (2016)
We looked at the differences between SRTM 90 m and ATL08 terrain with respect to the standard deviation of ground height (h_te_std) with respect to the interpolated ground surface (h_te_interp), which provides an indication of the surface roughness
Summary
The Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) mission (Markus et al, 2017; Neuman et al, 2019b) is the successor to the ICESat mission (Zwally et al, 2002; Schutz et al, 2005). ICESat-2 was launched on September 15th, 2018, into a 92° inclination, 500-km altitude, near-circular orbit. The mission aims primarily to monitor changes in the cryosphere, quantifying the contributions to sea-level change from glaciers, and ice sheets, and processes driving them, characterizing annual changes in thickness of sea ice to examine ice/ocean/atmosphere exchanges of energy, mass and moisture, and collecting valuable data to feed predictive models. ICESat-2 is collecting valuable scientific data globally, quantitatively characterizing topography and vegetation to measure vegetation canopy height as a basis for estimating large-scale biomass and biomass change, monitoring inland water, sea level changes, densely sampling the Earth’s surface and the atmosphere. The mission’s scientific objectives require tight vertical and horizontal accuracy of the measurements
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
