DOI: 10.5194/tc-11-2743-2017
Scopus记录号: 2-s2.0-85037700107
论文题名: Centuries of intense surface melt on Larsen C Ice Shelf
作者: Bevan S ; L ; , Luckman A ; , Hubbard B ; , Kulessa B ; , Ashmore D ; , Kuipers Munneke P ; , O'Leary M ; , Booth A ; , Sevestre H ; , McGrath D
刊名: Cryosphere
ISSN: 19940416
出版年: 2017
卷: 11, 期: 6 起始页码: 2743
结束页码: 2753
语种: 英语
英文关键词: ice cover
; ice shelf
; mountain region
; numerical model
; pond
; snow cover
; snowmelt
; spatial analysis
; Antarctic Peninsula
; Antarctica
; Cabinet Mountains
; Larsen Ice Shelf
; Rocky Mountains
; United States
; West Antarctica
英文摘要: Following a southward progression of ice-shelf disintegration along the Antarctic Peninsula (AP), Larsen C Ice Shelf (LCIS) has become the focus of ongoing investigation regarding its future stability. The ice shelf experiences surface melt and commonly features surface meltwater ponds. Here, we use a flow-line model and a firn density model (FDM) to date and interpret observations of melt-affected ice layers found within five 90ĝ€m boreholes distributed across the ice shelf. We find that units of ice within the boreholes, which have densities exceeding those expected under normal dry compaction metamorphism, correspond to two climatic warm periods within the last 300 years on the Antarctic Peninsula. The more recent warm period, from the 1960s onwards, has generated distinct sections of dense ice measured in two boreholes in Cabinet Inlet, which is close to the Antarctic Peninsula mountains - a region affected by föhn winds. Previous work has classified these layers as refrozen pond ice, requiring large quantities of mobile liquid water to form. Our flow-line model shows that, whilst preconditioning of the snow began in the late 1960s, it was probably not until the early 1990s that the modern period of ponding began. The earlier warm period occurred during the 18th century and resulted in two additional sections of anomalously dense ice deep within the boreholes. The first, at 61ĝ€m in one of our Cabinet Inlet boreholes, consists of ice characteristic of refrozen ponds and must have formed in an area currently featuring ponding. The second, at 69ĝ€m in a mid-shelf borehole, formed at the same time on the edge of the pond area. Further south, the boreholes sample ice that is of an equivalent age but which does not exhibit the same degree of melt influence. This west-east and north-south gradient in the past melt distribution resembles current spatial patterns of surface melt intensity. © Author(s) 2017. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/75469
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: Geography Department, College of Science, Swansea University, Singleton Park, Swansea, United Kingdom; Centre for Glaciology, Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, United Kingdom; School of Environmental Science, Roxby Building, University of Liverpool, Liverpool, United Kingdom; Institute for Marine and Atmospheric Research, Utrecht (IMAU), Utrecht University, P.O. Box 80000, Utrecht, Netherlands; School of Earth and Environment, University of Leeds, Leeds, United Kingdom; School of Geography and Geosciences, University of St.Andrews, College Gate, St.Andrews, United Kingdom; Department of Geosciences, Colorado State University, Fort Collins, CO, United States
Recommended Citation:
Bevan S,L,, Luckman A,et al. Centuries of intense surface melt on Larsen C Ice Shelf[J]. Cryosphere,2017-01-01,11(6)