A new approach to estimate ice dynamic rates using satellite
observations in East Antarctica
Bianca Kallenberg1, Paul Tregoning1, Janosch F. Hoffmann2, Rhys Hawkins1, Anthony Purcell1, and Sébastien Allgeyer11Research School of Earth Sciences, Australian National University, Canberra, ACT, 0200, Australia 2College of Computer, Mathematical, and Natural Science, University of Maryland, College Park, MD 20742, USA
Received: 23 Nov 2016 – Accepted for review: 30 Nov 2016 – Discussion started: 09 Dec 2016
Abstract. Mass balance changes of the Antarctic ice sheet are of significant interest due to its sensitivity to climatic changes and its contribution to changes in global sea level. While regional climate models successfully estimate mass input due to snowfall, it remains difficult to estimate the amount of mass loss due to ice dynamic processes. It's often been assumed that changes in ice dynamic rates only need to be considered when assessing long term ice sheet mass balance; however, two decades of satellite altimetry observations reveal that the Antarctic ice sheet changes unexpectedly and much more dynamically than previously expected. Despite available estimates on ice dynamic rates obtained from radar altimetry, information about changes in ice dynamic rates are still limited, especially in East Antarctica. Without understanding ice dynamic rates it is not possible to properly assess changes in ice sheet mass balance, surface elevation or to develop ice sheet models. In this study we investigate the possibility of estimating ice dynamic rates by removing modelled rates of surface mass balance, firn compaction and bedrock uplift from satellite altimetry and gravity observations. With similar rates of ice discharge acquired from two different satellite missions we show that it is possible to obtain an approximation of ice dynamic rates by combining altimetry and gravity observations. Thus, surface elevation changes due to surface mass balance, firn compaction and ice dynamic rates can be modelled and correlate with observed elevation changes from satellite altimetry.
Kallenberg, B., Tregoning, P., Hoffmann, J. F., Hawkins, R., Purcell, A., and Allgeyer, S.: A new approach to estimate ice dynamic rates using satellite
observations in East Antarctica, The Cryosphere Discuss., doi:10.5194/tc-2016-269, in review, 2016.