气候变化领域集成服务门户(CCPortal): Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event

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DOI	10.5194/tc-12-3123-2018
	Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event
	Miles B.; Stokes C.; Jamieson S.
发表日期	2018
ISSN	19940416
卷号	12 期号:10
英文摘要	Cook Glacier drains a large proportion of the Wilkes Subglacial Basin in East Antarctica, a region thought to be vulnerable to marine ice sheet instability and with potential to make a significant contribution to sea level. Despite its importance, there have been very few observations of its longer-term behaviour (e.g. of velocity or changes at its ice front). Here we use a variety of satellite imagery to produce a time series of ice front position change from 1947 to 2017 and ice velocity from 1973 to 2017. Cook Glacier has two distinct outlets (termed East and West), and we observe the near-complete loss of the Cook West Ice Shelf at some time between 1973 and 1989. This was associated with a doubling of the velocity of Cook West Glacier, which may also be linked to previously published reports of inland thinning. The loss of the Cook West Ice Shelf is surprising given that the present-day ocean climate conditions in the region are not typically associated with catastrophic ice shelf loss. However, we speculate that a more intense ocean climate forcing in the mid-20th century may have been important in forcing its collapse. Since the loss of the Cook West Ice Shelf, the presence of landfast sea ice and mélange in the newly formed embayment appears to be important in stabilizing the glacier front and enabling periodic advances. We also show that the last calving event at the larger Cook East Ice Shelf resulted in the retreat of its ice front into a dynamically important portion of the ice shelf and observe a short-lived increase in velocity of Cook East between 2006 and 2007, which we link to the drainage of subglacial Lake Cook. Taken together, these observations suggest that the velocity, and hence discharge, of Cook Glacier is highly sensitive to changes at its terminus, but a more detailed process-based analysis of this potentially vulnerable region requires further oceanic and bathymetric data. © Author(s) 2018.
语种	英语
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/119058
作者单位	Department of Geography, Durham University Science Site, South Road, Durham, DH1 3LE, United Kingdom
推荐引用方式 GB/T 7714	Miles B.,Stokes C.,Jamieson S.. Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event[J],2018,12(10).
APA	Miles B.,Stokes C.,&Jamieson S..(2018).Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event.Cryosphere,12(10).
MLA	Miles B.,et al."Velocity increases at Cook Glacier, East Antarctica, linked to ice shelf loss and a subglacial flood event".Cryosphere 12.10(2018).