DOI: 10.5194/tc-8-1807-2014
Scopus记录号: 2-s2.0-84908070960
论文题名: Surface velocity and mass balance of Livingston Island ice cap, Antarctica
作者: Osmanoglu B ; , Navarro F ; J ; , Hock R ; , Braun M ; , Corcuera M ; I
刊名: Cryosphere
ISSN: 19940416
出版年: 2014
卷: 8, 期: 5 起始页码: 1807
结束页码: 1823
语种: 英语
英文关键词: 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
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). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/74783
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
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作者单位: Geophysical Institute, University of Alaska Fairbanks, P.O. Box 757320, Fairbanks, Alaska, United States; Biospheric Sciences Lab., USRA-NASA, GSFC, Mail Stop 618.0, Greenbelt, MD, United States; Dept. Matemática Aplicada, ETSI de Telecomunicación, Universidad Politécnica de Madrid, Av. Complutense, 30, Madrid, Spain; Department of Earth Sciences, Uppsala University, Geocentrum, Villavägen 16, Uppsala, Sweden; Institute of Geography, University of Erlangen, Kochstrasse 4/4, Erlangen, Germany
Recommended Citation:
Osmanoglu B,, Navarro F,J,et al. Surface velocity and mass balance of Livingston Island ice cap, Antarctica[J]. Cryosphere,2014-01-01,8(5)