文章基本信息

标题：Reconstructing thermal properties of firn at Summit, Greenland, from a temperature profile time series
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作者：Alexandra L. Giese ; Robert L. Hawley
期刊名称：Journal of Glaciology
印刷版ISSN：0022-1430
电子版ISSN：1727-5652
出版年度：2015
卷号：61
期号：227
页码：503-510
DOI：10.3189/2015JoG14J204
出版社：Cambridge University Press
摘要：Abstract We have constrained the value for thermal diffusivity of near-surface snow and firn at Summit Station, Greenland, using a Fourier-type analysis applied to hourly temperature measurements collected from eight thermistors in a closed-off, air-filled borehole between May 2004 and July 2008. An implicit, finite-difference method suggests that a bulk diffusivity of ∼25 ± 3m 2 a −1 is the most reasonable for representing macroscale heat transport in the top 30 m of firn and snow. This value represents an average diffusivity and, in a conduction-only model, generates temperature series whose phase shifts with depth most closely match those of the Summit borehole data (rms difference between measurements and model output is ∼6 days). This bulk value, derived numerically and corroborated analytically, is useful over large tracts of the Greenland ice sheet where density and microstructure are unknown.
关键词：conduction;diffusivity;heat transfer;ice temperature;polar firn