气候变化领域集成服务门户(CCPortal): Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula

CCPortal

DOI	10.5194/tc-12-1347-2018
	Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula
	Friedl P.; Seehaus T.C.; Wendt A.; Braun M.H.; Höppner K.
发表日期	2018
ISSN	19940416
卷号	12 期号:4
英文摘要	The Antarctic Peninsula is one of the world's regions most affected by climate change. Several ice shelves have retreated, thinned or completely disintegrated during recent decades, leading to acceleration and increased calving of their tributary glaciers. Wordie Ice Shelf, located in Marguerite Bay at the south-western side of the Antarctic Peninsula, completely disintegrated in a series of events between the 1960s and the late 1990s. We investigate the longterm dynamics (1994-2016) of Fleming Glacier after the disintegration of Wordie Ice Shelf by analysing various multisensor remote sensing data sets. We present a dense time series of synthetic aperture radar (SAR) surface velocities that reveals a rapid acceleration of Fleming Glacier in 2008 and a phase of further gradual acceleration and upstream propagation of high velocities in 2010-2011.The timing in acceleration correlates with strong upwelling events of warm circumpolar deep water (CDW) intoWordie Bay, most likely leading to increased submarine melt. This, together with continuous dynamic thinning and a deep subglacial trough with a retrograde bed slope close to the terminus probably, has induced unpinning of the glacier tongue in 2008 and gradual grounding line retreat between 2010 and 2011. Our data suggest that the glacier's grounding line had retreated by 6-9 km between 1996 and 2011, which caused ∼56 km2 of the glacier tongue to go afloat. The resulting reduction in buttressing explains a median speedup of ∼1.3md-1 (∼27 %) between 2008 and 2011, which we observed along a centre line extending between the grounding line in 1996 and ∼16 km upstream. Current median ice thinning rates (2011-2014) along profiles in areas below 1000m altitude range between ∼2.6 to 3.2ma-1 and are ∼70% higher than between 2004 and 2008. Our study shows that Fleming Glacier is far away from approaching a new equilibrium and that the glacier dynamics are not primarily controlled by the loss of the former ice shelf anymore. Currently, the tongue of Fleming Glacier is grounded in a zone of bedrock elevation between ∼-400 and-500 m. However, about 3-4 km upstream modelled bedrock topography indicates a retrograde bed which transitions into a deep trough of up to ∼-1100m at ∼10 km upstream. Hence, this endangers upstream ice masses, which can significantly increase the contribution of Fleming Glacier to sea level rise in the future. © 2018 Author(s).
学科领域	acceleration; bottom topography; climate change; data set; glacier dynamics; grounding line; ice shelf; remote sensing; sensor; subglacial environment; synthetic aperture radar; upwelling; Antarctic Peninsula; Antarctica; Fleming Glacier; Marguerite Bay; West Antarctica; Wordie Ice Shelf
语种	英语
scopus关键词	acceleration; bottom topography; climate change; data set; glacier dynamics; grounding line; ice shelf; remote sensing; sensor; subglacial environment; synthetic aperture radar; upwelling; Antarctic Peninsula; Antarctica; Fleming Glacier; Marguerite Bay; West Antarctica; Wordie Ice Shelf
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/119177
作者单位	German Remote Sensing Data Center, German Aerospace Center, Oberpfaffenhofen, 82234, Germany; Institute of Geography, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, 91058, Germany; Bavarian Academy of Sciences and Humanities, Munich, 80539, Germany
推荐引用方式 GB/T 7714	Friedl P.,Seehaus T.C.,Wendt A.,et al. Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula[J],2018,12(4).
APA	Friedl P.,Seehaus T.C.,Wendt A.,Braun M.H.,&Höppner K..(2018).Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula.Cryosphere,12(4).
MLA	Friedl P.,et al."Recent dynamic changes on Fleming Glacier after the disintegration of Wordie Ice Shelf, Antarctic Peninsula".Cryosphere 12.4(2018).