气候变化领域集成服务门户(CCPortal): Ice-ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers

CCPortal

DOI	10.5194/tc-8-1457-2014
	Ice-ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers
	Chauché N.; Hubbard A.; Gascard J.-C.; Box J.E.; Bates R.; Koppes M.; Sole A.; Christoffersen P.; Patton H.
发表日期	2014
ISSN	19940416
卷号	8 期号:4
英文摘要	Warm, subtropical-originating Atlantic water (AW) has been identified as a primary driver of mass loss across the marine sectors of the Greenland Ice Sheet (GrIS), yet the specific processes by which this water mass interacts with and erodes the calving front of tidewater glaciers is frequently modelled and much speculated upon but remains largely unobserved. We present a suite of fjord salinity, temperature, turbidity versus depth casts along with glacial runoff estimation from Rink and Store glaciers, two major marine outlets draining the western sector of the GrIS during 2009 and 2010. We characterise the main water bodies present and interpret their interaction with their respective calving fronts. We identify two distinct processes of ice-ocean interaction which have distinct spatial and temporal footprints: (1) homogenous free convective melting which occurs across the calving front where AW is in direct contact with the ice mass, and (2) localised upwelling-driven melt by turbulent subglacial runoff mixing with fjord water which occurs at distinct injection points across the calving front. Throughout the study, AW at 2.8 ± 0.2 °C was consistently observed in contact with both glaciers below 450 m depth, yielding homogenous, free convective submarine melting up to ∼200 m depth. Above this bottom layer, multiple interactions are identified, primarily controlled by the rate of subglacial fresh-water discharge which results in localised and discrete upwelling plumes. In the record melt year of 2010, the Store Glacier calving face was dominated by these runoff-driven plumes which led to a highly crenulated frontal geometry characterised by large embayments at the subglacial portals separated by headlands which are dominated by calving. Rink Glacier, which is significantly deeper than Store has a larger proportion of its submerged calving face exposed to AW, which results in a uniform, relatively flat overall frontal geometry. © 2014 Auhtor(s).
学科领域	fjord; freshwater input; ice sheet; ice-ocean interaction; iceberg calving; runoff; subglacial environment; tidewater glacier; Arctic; Greenland; Greenland Ice Sheet; West Greenland
语种	英语
scopus关键词	fjord; freshwater input; ice sheet; ice-ocean interaction; iceberg calving; runoff; subglacial environment; tidewater glacier; Arctic; Greenland; Greenland Ice Sheet; West Greenland
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/120073
作者单位	Department of Geography and Earth Science, Aberystwyth University, Aberystwyth, United Kingdom; Laboratoroire d'Océanographie et du Climat, Expérimentation et Approche Numérique, Université Pierre et Marie Curie, Paris, France; Byrd Polar Research Center, Ohio State University, Columbus, OH, United States; Geological Survey of Denmark and Greenland, Copenhagen, Denmark; School of Geography and Geosciences, St-Andrews University, St-Andrews, United Kingdom; Department of Geography, University of British Columbia, Vancouver, Canada; Department of Geography, University of Sheffield, Sheffield, United Kingdom; Scott Polar Research Institute, University of Cambridge, Cambridge, United Kingdom
推荐引用方式 GB/T 7714	Chauché N.,Hubbard A.,Gascard J.-C.,et al. Ice-ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers[J],2014,8(4).
APA	Chauché N..,Hubbard A..,Gascard J.-C..,Box J.E..,Bates R..,...&Patton H..(2014).Ice-ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers.Cryosphere,8(4).
MLA	Chauché N.,et al."Ice-ocean interaction and calving front morphology at two west Greenland tidewater outlet glaciers".Cryosphere 8.4(2014).