气候变化领域集成服务门户(CCPortal): Strong changes in englacial temperatures despite insignificant changes in ice thickness at Dôme du Goûter glacier (Mont Blanc area)

CCPortal

DOI	10.5194/tc-14-925-2020
	Strong changes in englacial temperatures despite insignificant changes in ice thickness at Dôme du Goûter glacier (Mont Blanc area)
	Vincent C.; Gilbert A.; Jourdain B.; Piard L.; Ginot P.; Mikhalenko V.; Possenti P.; Le Meur E.; Laarman O.; Six D.
发表日期	2020
ISSN	19940416
起始页码	925
结束页码	934
卷号	14 期号:3
英文摘要	The response of very-high-elevation glaciated areas on Mont Blanc to climate change has been analysed using observations and numerical modelling over the last 2 decades. Unlike the changes at low elevations, we observe very low glacier thickness changes, of about-2:6m on average since 1993. The slight changes in horizontal ice flow velocities and submergence velocities suggest a decrease of about 10% in ice flux and surface mass balance. This is due to less snow accumulation and is consistent with the precipitation decrease observed in meteorological data. Conversely, measurements performed in deep boreholes since 1994 reveal strong changes in englacial temperature reaching a 1.5 °C increase at a depth of 50 m. We conclude that at such very high elevations, current changes in climate do not lead to visible changes in glacier thickness but cause invisible changes within the glacier in terms of englacial temperatures. Our analysis from numerical modelling shows that glacier near-surface temperature warming is enhanced by increasing melt frequency at high elevations although the impact on surface mass balance is low. This results in a non-linear response of englacial temperature to currently rising air temperatures. In addition, borehole temperature inversion including a new dataset confirms previous findings of similar air temperature changes at high and low elevations in the Alps. © Author(s) 2020.
英文关键词	air temperature; borehole; climate change; glacier; glacier advance; glacier mass balance; ice flow; ice thickness; snow accumulation; temperature inversion; Alps; Haute Savoie; Mont Blanc; Savoy Alps; Western Alps
语种	英语
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/202235
作者单位	Univ. Grenoble Alpes, CNRS, IRD, Grenoble INP, IGE, Grenoble, 38000, France; Institute of Geography, Russian Academy of Sciences, Moscow, Russian Federation
推荐引用方式 GB/T 7714	Vincent C.,Gilbert A.,Jourdain B.,et al. Strong changes in englacial temperatures despite insignificant changes in ice thickness at Dôme du Goûter glacier (Mont Blanc area)[J],2020,14(3).
APA	Vincent C..,Gilbert A..,Jourdain B..,Piard L..,Ginot P..,...&Six D..(2020).Strong changes in englacial temperatures despite insignificant changes in ice thickness at Dôme du Goûter glacier (Mont Blanc area).Cryosphere,14(3).
MLA	Vincent C.,et al."Strong changes in englacial temperatures despite insignificant changes in ice thickness at Dôme du Goûter glacier (Mont Blanc area)".Cryosphere 14.3(2020).