The Cryosphere, 11, 2655–2674, 2017 https://doi.org/10.5194/tc-11-2655-2017 © Author(s) 2017. This work is distributed under the Creative Commons Attribution 3.0 License. GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica David E. Shean1,2, Knut Christianson3, Kristine M. Larson4, Stefan R. M. Ligtenberg5, Ian R. Joughin1, Ben E. Smith1, C. Max Stevens3, Mitchell Bushuk6, and David M. Holland7,8 1Applied Physics Laboratory Polar Science Center, University of Washington, Seattle, WA, USA 2Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA 3Department of Earth and Space Sciences, University of Washington, Seattle, WA, USA 4Department of Aerospace Engineering Sciences, University of Colorado, Boulder, CO, USA 5Institute for Marine and Atmospheric research Utrecht, Utrecht University, Utrecht, the Netherlands 6Geophysical Fluid Dynamics Laboratory, Princeton University, Princeton, NJ, USA 7Courant Institute of Mathematical Sciences, New York University, New York, NY, USA 8Center for Global Sea-Level Change, New York University, Abu Dhabi, United Arab Emirates Correspondence to: David E. Shean (
[email protected]) Received: 17 December 2016 – Discussion started: 3 January 2017 Revised: 22 September 2017 – Accepted: 29 September 2017 – Published: 21 November 2017 Abstract. In the last 2 decades, Pine Island Glacier (PIG) ex- show limited temporal variability despite large changes in perienced marked speedup, thinning, and grounding-line re- ocean temperature recorded by moorings in Pine Island Bay. treat, likely due to marine ice-sheet instability and ice-shelf Our results demonstrate the value of long-term GPS records basal melt.