气候变化领域集成服务门户(CCPortal): Thermal Responses to Antarctic Ice Shelf Melt in an Eddy-Rich Global Ocean-Sea Ice Model

CCPortal

DOI	10.1175/JCLI-D-19-0846.1
	Thermal Responses to Antarctic Ice Shelf Melt in an Eddy-Rich Global Ocean-Sea Ice Model
	Moorman R.; Morrison A.K.; Hogg A.M.
发表日期	2020
ISSN	0894-8755
起始页码	6599
结束页码	6620
卷号	33 期号:15
英文摘要	The response of near-Antarctic waters to freshening by increased glacial melt is investigated using a highresolution (0.18) global ocean-sea ice model with realistic Antarctic water-mass properties. Two meltwater perturbation experiments are conducted where the ocean model is forced with constant elevated glacial melt rates of 1.5 and 2.8 times the control rate. Within 10 years of the onset of enhanced meltwater forcing, the generation of Antarctic Bottom Water from Dense Shelf Water ceases, as shelf waters become increasingly buoyant. Increased ocean stratification triggers subsurface warming in Dense Shelf Water source regions, suggesting a localized positive feedback to melt. In a parallel response, meltwater forcing enhances the subsurface lateral density gradients of the Antarctic Slope Front that modulate the transport of warm Circumpolar Deep Water across the continental slope toward ice shelf grounding lines. Consequently, coastal freshening acts to isolate the Antarctic Ice Sheet from open ocean heat, suggesting a cooling response to melt that counteracts warming associated with stratification. Further, these strengthening density gradients accelerate westward geostrophic currents along the coast and shelf break, homogenizing shelf waters and amplifying remote feedbacks. The net effect on the continental shelf is transient warming, followed by cooling in both experiments; however, this signal is the aggregate of a complex pattern of regional warming and cooling responses. These results suggest coastal freshening by meltwater may alter the thermal forcing of the Antarctic ice sheet in ways that both accelerate and inhibit ice shelf melt at different locations along the Antarctic coastline. © 2020 American Meteorological Society. All rights reserved.
英文关键词	Feedback; Glacial geology; Glaciers; Ocean currents; Sea ice; Antarctic Bottom Water; Antarctic ice sheets; Antarctic ice shelves; Continental shelves; Ocean stratification; Subsurface warming; Water-mass properties; Westward geostrophic current; Cooling; circumpolar current; glaciology; ice shelf; meltwater; sea ice; shelf break; stratification; water mass; Antarctic Ice Sheet; Antarctica
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171202
作者单位	Research School of Earth Sciences, Arc Centre of Excellence for Climate Extremes, Australian National University, Australian Capital Territory, Canberra, Australia
推荐引用方式 GB/T 7714	Moorman R.,Morrison A.K.,Hogg A.M.. Thermal Responses to Antarctic Ice Shelf Melt in an Eddy-Rich Global Ocean-Sea Ice Model[J],2020,33(15).
APA	Moorman R.,Morrison A.K.,&Hogg A.M..(2020).Thermal Responses to Antarctic Ice Shelf Melt in an Eddy-Rich Global Ocean-Sea Ice Model.Journal of Climate,33(15).
MLA	Moorman R.,et al."Thermal Responses to Antarctic Ice Shelf Melt in an Eddy-Rich Global Ocean-Sea Ice Model".Journal of Climate 33.15(2020).