Response of the Energy Balance on the Margin of the Greenland Ice Sheet to Temperature Changes

Abstract Daily ice ablation on two outlet glaciers from the Greenland ice sheet, Nordbogletscher (1979–83) and Qamanârssûp sermia (1980–86), is related to air temperature by a linear regression equation. Analysis of this ablation-temperature equation with the help of a simple energy-balance model sh...

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Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Braithwaite, Roger J., Olesen, Ole B.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1990
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022143000009461
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000009461
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Summary:Abstract Daily ice ablation on two outlet glaciers from the Greenland ice sheet, Nordbogletscher (1979–83) and Qamanârssûp sermia (1980–86), is related to air temperature by a linear regression equation. Analysis of this ablation-temperature equation with the help of a simple energy-balance model shows that sensible-heat flux has the greatest temperature response and accounts for about one-half of the temperature response of ablation. Net radiation accounts for about one-quarter of the temperature response of ablation, and latent-heat flux and errors account for the remainder. The temperature response of sensible-heat flux at QQamanârssûp sermia is greater than at Nordbogletscher mainly due to higher average wind speeds. The association of high winds with high temperatures during Föhn events further increases sensible-heat flux. The energy-balance model shows that ablation from a snow surface is only about half that from an ice surface at the same air temperature.