气候变化领域集成服务门户(CCPortal): GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica

CCPortal

DOI	10.5194/tc-11-2655-2017
	GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica
	Shean D.E.; Christianson K.; Larson K.M.; Ligtenberg S.R.M.; Joughin I.R.; Smith B.E.; Max Stevens C.; Bushuk M.; Holland D.M.
发表日期	2017
ISSN	19940416
卷号	11 期号:6
英文摘要	In the last 2 decades, Pine Island Glacier (PIG) experienced marked speedup, thinning, and grounding-line retreat, likely due to marine ice-sheet instability and ice-shelf basal melt. To better understand these processes, we combined 2008-2010 and 2012-2014 GPS records with dynamic firn model output to constrain local surface and basal mass balance for PIG. We used GPS interferometric reflectometry to precisely measure absolute surface elevation (Zsurf) and Lagrangian surface elevation change (DZsurf/Dt). Observed surface elevation relative to a firn layer tracer for the initial surface (Zsurf-Zsurf()') is consistent with model estimates of surface mass balance (SMB, primarily snow accumulation). A relatively abrupt ĝ1/4 ĝ0.2-0.3ĝm surface elevation decrease, likely due to surface melt and increased compaction rates, is observed during a period of warm atmospheric temperatures from December 2012 to January 2013. Observed DZsurf/Dt trends (-1 to -4 m yr-1) for the PIG shelf sites are all highly linear. Corresponding basal melt rate estimates range from ∼ 10 to 40m yr-1, in good agreement with those derived from ice-bottom acoustic ranging, phase-sensitive ice-penetrating radar, and high-resolution stereo digital elevation model (DEM) records. The GPS and DEM records document higher melt rates within and near features associated with longitudinal extension (i.e., transverse surface depressions, rifts). Basal melt rates for the 2012-2014 period show limited temporal variability despite large changes in ocean temperature recorded by moorings in Pine Island Bay. Our results demonstrate the value of long-term GPS records for ice-shelf mass balance studies, with implications for the sensitivity of ice-ocean interaction at PIG. © Author(s) 2017.
学科领域	air temperature; basal melting; digital elevation model; estimation method; GPS; ice retreat; ice shelf; ice-ocean interaction; snow accumulation; Antarctica; Pine Island Bay; Pine Island Glacier; West Antarctica
语种	英语
scopus关键词	air temperature; basal melting; digital elevation model; estimation method; GPS; ice retreat; ice shelf; ice-ocean interaction; snow accumulation; Antarctica; Pine Island Bay; Pine Island Glacier; West Antarctica
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119306
作者单位	Applied Physics Laboratory Polar Science Center, University of Washington, Seattle, WA, United States; Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States; Department of Earth and Space Sciences, University of Washington, Seattle, WA, United States; Department of Aerospace Engineering Sciences, University of Colorado, Boulder, CO, United States; Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, Netherlands; Geophysical Fluid Dynamics Laboratory, Princeton University, Princeton, NJ, United States; Courant Institute of Mathematical Sciences, New York University, New York, NY, United States; Center for Global Sea-Level Change, New York University, Abu Dhabi, United Arab Emirates
推荐引用方式 GB/T 7714	Shean D.E.,Christianson K.,Larson K.M.,et al. GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica[J],2017,11(6).
APA	Shean D.E..,Christianson K..,Larson K.M..,Ligtenberg S.R.M..,Joughin I.R..,...&Holland D.M..(2017).GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica.Cryosphere,11(6).
MLA	Shean D.E.,et al."GPS-derived estimates of surface mass balance and ocean-induced basal melt for Pine Island Glacier ice shelf, Antarctica".Cryosphere 11.6(2017).