C53C-0787
Development of a multi-sensor elevation time series pole-ward of 86°S in support of altimetry validation and ice sheet mass balance studies
Friday, 18 December 2015
Poster Hall (Moscone South)
Michael Studinger1, Kelly M Brunt2, Kimberly Casey3, Brooke Medley1, Tom Neumann4, Serdar Manizade5 and Matthew A. Linkswiler6, (1)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (2)Goddard Earth Sciences Technology and Research, Greenbelt, MD, United States, (3)Earth System Science Interdisciplinary Center, COLLEGE PARK, MD, United States, (4)NASA Goddard Space Flight Ctr., Greenbelt, MD, United States, (5)URS Inc., Wallops Island, VA, United States, (6)URS Corporation, Wallops Island Remote Sensing, San Francisco, CA, United States
Abstract:
In order to produce a cross-calibrated long-term record of ice-surface elevation change for input into ice sheet models and mass balance studies it is necessary to “link the measurements made by airborne laser altimeters, satellite measurements of ICESat, ICESat-2, and CryoSat-2” [
IceBridge Level 1 Science Requirements, 2012] and determine the biases and the spatial variations between radar altimeters and laser altimeters using different wavelengths. The convergence zones of all ICESat tracks (86°S) and all ICESat-2 and CryoSat-2 tracks (88°S) are in regions of relatively low accumulation, making them ideal for satellite altimetry calibration. In preparation for ICESat-2 validation, the IceBridge and ICESat-2 science teams have designed IceBridge data acquisitions around 86°S and 88°S. Several aspects need to be considered when comparing and combining elevation measurements from different radar and laser altimeters, including: a) foot print size and spatial sampling pattern; b) accuracy and precision of each data sets; c) varying signal penetration into the snow; and d) changes in geodetic reference frames over time, such as the International Terrestrial Reference Frame (ITRF). The presentation will focus on the analysis of several IceBridge flights around 86 and 88°S with the LVIS and ATM airborne laser altimeters and will evaluate the accuracy and precision of these data sets. To properly interpret the observed elevation change (dh/dt) as mass change, however, the various processes that control surface elevation fluctuations must be quantified and therefore future work will quantify the spatial variability in snow accumulation rates pole-ward of 86°S and in particular around 88°S. Our goal is to develop a cross-validated multi-sensor time series of surface elevation change pole-ward of 86°S that, in combination with measured accumulation rates, will support ICESat-2 calibration and validation and ice sheet mass balance studies.
