DOI: 10.5194/tc-10-2043-2016
Scopus记录号: 2-s2.0-84987713278
论文题名: Grounding and calving cycle of Mertz Ice Tongue revealed by shallow Mertz Bank
作者: Wang X ; , Holland D ; M ; , Cheng X ; , Gong P
刊名: Cryosphere
ISSN: 19940416
出版年: 2016
卷: 10, 期: 5 起始页码: 2043
结束页码: 2056
语种: 英语
英文关键词: estimation method
; GLAS
; grounding line
; ice flow
; iceberg calving
; ICESat
; remote sensing
; sea surface height
; seafloor mapping
; Antarctica
; East Antarctica
; Mertz Glacier
英文摘要: A recent study, using remote sensing, provided evidence that a seafloor shoal influenced the 2010 calving event of the Mertz Ice Tongue (MIT), by partially grounding the MIT several years earlier. In this paper, we start by proposing a method to calculate firn air content (FAC) around Mertz from seafloor-touching icebergs. Our calculations indicate the FAC around Mertz region as 4.87±1.31 m. We then design an indirect method of using freeboard and sea surface height data extracted from ICESat/GLAS, FAC, and relatively accurate seafloor topography to detect grounding sections of the MIT between 2002 and 2008 and analyze the process of grounding prior to the calving event. By synthesizing remote sensing data, we point out that the grounding position was localized northeast of the Mertz ice front close to the Mertz Bank. The grounding outlines of the tongue caused by the Mertz Bank are extracted as well. From 2002 to 2008, the grounding area increased and the grounding became more pronounced. Additionally, the ice tongue could not effectively climb over the Mertz Bank in following the upstream ice flow direction and that is why MIT rotated clockwise after late 2002. Furthermore, we demonstrate that the area-increasing trend of the MIT changed little after calving (∼36 km2 a-1), thus allowing us to use remote sensing to estimate the elapsed time until the MIT can reground on and be bent by the shoal. This period is approximately 70 years. Our observations suggest that the calving of the MIT is a cyclical process controlled by the presence of the shallow Mertz Bank location and the flow rate of the tongue. This calving cycle also explains the cyclic variations in seasurface conditions around the Mertz detected by earlier studies. © Author(s) 2016. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/75083
Appears in Collections: 影响、适应和脆弱性 气候变化与战略
There are no files associated with this item.
作者单位: Center for Global Sea Level Change, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates; State Key Laboratory of Remote Sensing Science, College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; Courant Institute of Mathematical Sciences, New York University, New York, United States; Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Tsinghua University, Beijing, China; Joint Centre for Global Change Studies, Beijing, China
Recommended Citation:
Wang X,, Holland D,M,et al. Grounding and calving cycle of Mertz Ice Tongue revealed by shallow Mertz Bank[J]. Cryosphere,2016-01-01,10(5)