Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements
Accurate description of snow and firn processes is necessary for estimating the fraction of glacier surface melt that contributes to runoff. Most processes in snow and firn are to a great extent controlled by the temperature therein and in the absence of liquid water, the temperature evolution is do...
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ftunivutrecht:oai:dspace.library.uu.nl:1874/383709 2023-11-12T04:17:33+01:00 Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements Marchenko, Sergey Cheng, Gong Lötstedt, Per Pohjola, Veijo Pettersson, Rickard Van Pelt, Ward Reijmer, Carleen Sub Dynamics Meteorology Marine and Atmospheric Research 2019-07-09 image/pdf https://dspace.library.uu.nl/handle/1874/383709 en eng 1994-0416 https://dspace.library.uu.nl/handle/1874/383709 info:eu-repo/semantics/OpenAccess Water Science and Technology Earth-Surface Processes Article 2019 ftunivutrecht 2023-11-01T23:21:01Z Accurate description of snow and firn processes is necessary for estimating the fraction of glacier surface melt that contributes to runoff. Most processes in snow and firn are to a great extent controlled by the temperature therein and in the absence of liquid water, the temperature evolution is dominated by the conductive heat exchange. The latter is controlled by the effective thermal conductivity. Here we reconstruct the effective thermal conductivity of firn at Lomonosovfonna, Svalbard, using an optimization routine minimizing the misfit between simulated and measured subsurface temperatures and densities. The optimized values in the range from 0.2 to 1.6 W (m K)-1 increase downwards and over time. The results are supported by uncertainty quantification experiments, according to which is most sensitive to systematic errors in empirical temperature values and their estimated depths, particularly in the lower part of the vertical profile. Compared to commonly used density-based parameterizations, our values are consistently larger, suggesting a faster conductive heat exchange in firn. Article in Journal/Newspaper glacier Svalbard Utrecht University Repository Lomonosovfonna ENVELOPE(17.663,17.663,78.774,78.774) Svalbard |
institution |
Open Polar |
collection |
Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
English |
topic |
Water Science and Technology Earth-Surface Processes |
spellingShingle |
Water Science and Technology Earth-Surface Processes Marchenko, Sergey Cheng, Gong Lötstedt, Per Pohjola, Veijo Pettersson, Rickard Van Pelt, Ward Reijmer, Carleen Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
topic_facet |
Water Science and Technology Earth-Surface Processes |
description |
Accurate description of snow and firn processes is necessary for estimating the fraction of glacier surface melt that contributes to runoff. Most processes in snow and firn are to a great extent controlled by the temperature therein and in the absence of liquid water, the temperature evolution is dominated by the conductive heat exchange. The latter is controlled by the effective thermal conductivity. Here we reconstruct the effective thermal conductivity of firn at Lomonosovfonna, Svalbard, using an optimization routine minimizing the misfit between simulated and measured subsurface temperatures and densities. The optimized values in the range from 0.2 to 1.6 W (m K)-1 increase downwards and over time. The results are supported by uncertainty quantification experiments, according to which is most sensitive to systematic errors in empirical temperature values and their estimated depths, particularly in the lower part of the vertical profile. Compared to commonly used density-based parameterizations, our values are consistently larger, suggesting a faster conductive heat exchange in firn. |
author2 |
Sub Dynamics Meteorology Marine and Atmospheric Research |
format |
Article in Journal/Newspaper |
author |
Marchenko, Sergey Cheng, Gong Lötstedt, Per Pohjola, Veijo Pettersson, Rickard Van Pelt, Ward Reijmer, Carleen |
author_facet |
Marchenko, Sergey Cheng, Gong Lötstedt, Per Pohjola, Veijo Pettersson, Rickard Van Pelt, Ward Reijmer, Carleen |
author_sort |
Marchenko, Sergey |
title |
Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
title_short |
Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
title_full |
Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
title_fullStr |
Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
title_full_unstemmed |
Thermal conductivity of firn at Lomonosovfonna, Svalbard, derived from subsurface temperature measurements |
title_sort |
thermal conductivity of firn at lomonosovfonna, svalbard, derived from subsurface temperature measurements |
publishDate |
2019 |
url |
https://dspace.library.uu.nl/handle/1874/383709 |
long_lat |
ENVELOPE(17.663,17.663,78.774,78.774) |
geographic |
Lomonosovfonna Svalbard |
geographic_facet |
Lomonosovfonna Svalbard |
genre |
glacier Svalbard |
genre_facet |
glacier Svalbard |
op_relation |
1994-0416 https://dspace.library.uu.nl/handle/1874/383709 |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782334387426164736 |