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DOI	10.5194/tc-13-2579-2019
	Spatial and temporal variations in basal melting at Nivlisen ice shelf, East Antarctica, derived from phase-sensitive radars
	Lindbäck K.; Moholdt G.; Nicholls K.W.; Hattermann T.; Pratap B.; Thamban M.; Matsuoka K.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	2579
结束页码	2595
卷号	13 期号:10
英文摘要	Thinning rates of ice shelves vary widely around Antarctica, and basal melting is a major component of ice shelf mass loss. In this study, we present records of basal melting at a unique spatial and temporal resolution for East Antarctica, derived from autonomous phase-sensitive radars. These records show spatial and temporal variations of basal melting in 2017 and 2018 at Nivlisen, an ice shelf in central Dronning Maud Land. The annually averaged basal melt rates are in general moderate (∼0.8myr-1). Radar profiling of the ice shelf shows variable ice thickness from smooth beds to basal crevasses and channels. The highest basal melt rates (3.9myr-1) were observed close to a grounded feature near the ice shelf front. Daily time-varying measurements reveal a seasonal melt signal 4km from the ice shelf front, at an ice draft of 130m, where the highest daily basal melt rates occurred in summer (up to 5.6myr-1). In comparison with wind, air temperatures, and sea ice cover from reanalysis and satellite data, the seasonality in basal melt rates indicates that summer-warmed ocean surface water was pushed by wind beneath the ice shelf front. We observed a different melt regime 35km into the ice shelf cavity, at an ice draft of 280m, with considerably lower basal melt rates (annual average of 0.4myr-1) and no seasonality. We conclude that warm deep-ocean water at present has a limited effect on the basal melting of Nivlisen. On the other hand, a warming in surface waters, as a result of diminishing sea ice cover, has the potential to increase basal melting near the ice shelf front. Continuous in situ monitoring of Antarctic ice shelves is needed to understand the complex mechanisms involved in ice shelf-ocean interactions. © 2019 Author(s).
学科领域	basal melting; ice cover; ice shelf; ice thickness; radar; satellite data; sea ice; sea surface; seasonality; spatiotemporal analysis; surface water; Antarctica; East Antarctica; Queen Maud Land
语种	英语
scopus关键词	basal melting; ice cover; ice shelf; ice thickness; radar; satellite data; sea ice; sea surface; seasonality; spatiotemporal analysis; surface water; Antarctica; East Antarctica; Queen Maud Land
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118830
作者单位	Norwegian Polar Institute, Framsenteret, Postboks 6606, Langnes, Tromsø, 9296, Norway; British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Rd, Cambridge, CB30ET, United Kingdom; National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Government of India, Headland Sada, Vasco-da-Gama, Goa, 403804, India
推荐引用方式 GB/T 7714	Lindbäck K.,Moholdt G.,Nicholls K.W.,et al. Spatial and temporal variations in basal melting at Nivlisen ice shelf, East Antarctica, derived from phase-sensitive radars[J],2019,13(10).
APA	Lindbäck K..,Moholdt G..,Nicholls K.W..,Hattermann T..,Pratap B..,...&Matsuoka K..(2019).Spatial and temporal variations in basal melting at Nivlisen ice shelf, East Antarctica, derived from phase-sensitive radars.The Cryosphere,13(10).
MLA	Lindbäck K.,et al."Spatial and temporal variations in basal melting at Nivlisen ice shelf, East Antarctica, derived from phase-sensitive radars".The Cryosphere 13.10(2019).