气候变化领域集成服务门户(CCPortal): Surface velocity and mass balance of Livingston Island ice cap, Antarctica

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DOI	10.5194/tc-8-1807-2014
	Surface velocity and mass balance of Livingston Island ice cap, Antarctica
	Osmanoglu B.; Navarro F.J.; Hock R.; Braun M.; Corcuera M.I.
发表日期	2014
ISSN	19940416
卷号	8 期号:5
英文摘要	The mass budget of the ice caps surrounding the Antarctica Peninsula and, in particular, the partitioning of its main components are poorly known. Here we approximate frontal ablation (i.e. the sum of mass losses by calving and submarine melt) and surface mass balance of the ice cap of Livingston Island, the second largest island in the South Shetland Islands archipelago, and analyse variations in surface velocity for the period 2007-2011. Velocities are obtained from feature tracking using 25 PALSAR-1 images, and used in conjunction with estimates of glacier ice thicknesses inferred from principles of glacier dynamics and ground-penetrating radar observations to estimate frontal ablation rates by a flux-gate approach. Glacier-wide surface mass-balance rates are approximated from in situ observations on two glaciers of the ice cap. Within the limitations of the large uncertainties mostly due to unknown ice thicknesses at the flux gates, we find that frontal ablation (−509 ± 263 Mt yr-1, equivalent to −0.73 ± 0.38 m w.e. yr-1 over the ice cap area of 697 km2) and surface ablation (−0.73 ± 0.10 m w.e. yr-1) contribute similar shares to total ablation (−1.46 ± 0.39 m w.e. yr-1). Total mass change (δM Combining double low line −0.67 ± 0.40 m w.e. yr-1) is negative despite a slightly positive surface mass balance (0.06 ± 0.14 m w.e. yr-1). We find large interannual and, for some basins, pronounced seasonal variations in surface velocities at the flux gates, with higher velocities in summer than in winter. Associated variations in frontal ablation (of ∼237 Mt yr-1; −0.34 m w.e. yr-1) highlight the importance of taking into account the seasonality in ice velocities when computing frontal ablation with a flux-gate approach. © 2014 Author(s).
学科领域	ablation; frontal feature; glacier mass balance; ground penetrating radar; ice cap; ice thickness; PALSAR; satellite imagery; seasonal variation; temporal period; Antarctica; Livingston Island; South Shetland Islands
语种	英语
scopus关键词	ablation; frontal feature; glacier mass balance; ground penetrating radar; ice cap; ice thickness; PALSAR; satellite imagery; seasonal variation; temporal period; Antarctica; Livingston Island; South Shetland Islands
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/120048
作者单位	Geophysical Institute, University of Alaska Fairbanks, P.O. Box 757320, Fairbanks, Alaska, 99775, United States; Biospheric Sciences Lab., USRA-NASA, GSFC, Mail Stop 618.0, Greenbelt, MD 20771, United States; Dept. Matemática Aplicada, ETSI de Telecomunicación, Universidad Politécnica de Madrid, Av. Complutense, 30, Madrid, 28040, Spain; Department of Earth Sciences, Uppsala University, Geocentrum, Villavägen 16, Uppsala, 75236, Sweden; Institute of Geography, University of Erlangen, Kochstrasse 4/4, Erlangen, 91054, Germany
推荐引用方式 GB/T 7714	Osmanoglu B.,Navarro F.J.,Hock R.,et al. Surface velocity and mass balance of Livingston Island ice cap, Antarctica[J],2014,8(5).
APA	Osmanoglu B.,Navarro F.J.,Hock R.,Braun M.,&Corcuera M.I..(2014).Surface velocity and mass balance of Livingston Island ice cap, Antarctica.Cryosphere,8(5).
MLA	Osmanoglu B.,et al."Surface velocity and mass balance of Livingston Island ice cap, Antarctica".Cryosphere 8.5(2014).