Document Type
Article
Publication Date
4-14-2015
Publication Title
Journal of Glaciology
Department
Department of Earth Sciences
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 ± 3m2 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.
DOI
10.3189/2015JoG14J204
Dartmouth Digital Commons Citation
Giese, Alexandra L. and Hawley, Robert L., "Reconstructing Thermal Properties of Firn at Summit, Greenland, from a Temperature Profile Time Series" (2015). Dartmouth Scholarship. 1751.
https://digitalcommons.dartmouth.edu/facoa/1751
