气候变化领域集成服务门户(CCPortal): Cold Ocean Cavity and Weak Basal Melting of the Sørsdal Ice Shelf Revealed by Surveys Using Autonomous Platforms

CCPortal

DOI	10.1029/2019JC015882
	Cold Ocean Cavity and Weak Basal Melting of the Sørsdal Ice Shelf Revealed by Surveys Using Autonomous Platforms
	Gwyther D.E.; Spain E.A.; King P.; Guihen D.; Williams G.D.; Evans E.; Cook S.; Richter O.; Galton-Fenzi B.K.; Coleman R.
发表日期	2020
ISSN	21699275
卷号	125 期号:6
英文摘要	Basal melting of ice shelves is inherently difficult to quantify through direct observations, yet it is a critical factor controlling Antarctic mass balance and global sea-level rise. While much research attention is paid to larger ice shelves and those experiencing the most rapid change, many smaller, unstudied ice shelves offer valuable insights. Here, we investigate the oceanographic conditions and melting beneath the Sørsdal ice shelf, East Antarctica. We present results from the 2018/2019 Sørsdal deployment of the University of Tasmania's autonomous underwater vehicle nupiri muka. Oceanography adjacent to and beneath the ice shelf front shows a cold and relatively saline environment dominated by Winter Water and Dense Shelf Water, while bathymetry measurements show a deep (∼1,200 m) trough running into the ice shelf cavity. Two multiyear deployments of Autonomous Phase-sensitive Radar Echo Sounders on the surface of the ice shelf show weak melt rates (average of 1.6 and 2.3 m yr−1) with low temporal variability. These observations are supported by numerical ocean model and satellite estimates of melting. We speculate that the presence of a ∼825 m thick (350 m to at least 1,175 m) homogeneous layer of cold, dense water blocks access from warmer waters that intrude into Prydz Bay from offshore, resulting in weak melt rates. However, the newly identified trough means that the ice shelf is vulnerable to any decrease in polynya activity that allows warm water to enter the cavity. This could lead to increased basal melting and mass loss through this sector of Antarctica. ©2020. The Authors.
英文关键词	Antarctica; APRES; AUV; basal melting; ice shelves; oceanography
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186828
作者单位	Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS, Australia; Australian Maritime College, University of Tasmania, Launceston, TAS, Australia; Antarctic Climate & Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS, Australia; Australian Antarctic Division, Kingston, TAS, Australia
推荐引用方式 GB/T 7714	Gwyther D.E.,Spain E.A.,King P.,et al. Cold Ocean Cavity and Weak Basal Melting of the Sørsdal Ice Shelf Revealed by Surveys Using Autonomous Platforms[J],2020,125(6).
APA	Gwyther D.E..,Spain E.A..,King P..,Guihen D..,Williams G.D..,...&Coleman R..(2020).Cold Ocean Cavity and Weak Basal Melting of the Sørsdal Ice Shelf Revealed by Surveys Using Autonomous Platforms.Journal of Geophysical Research: Oceans,125(6).
MLA	Gwyther D.E.,et al."Cold Ocean Cavity and Weak Basal Melting of the Sørsdal Ice Shelf Revealed by Surveys Using Autonomous Platforms".Journal of Geophysical Research: Oceans 125.6(2020).