Characterising englacial R-channels using artificial moulins
The englacial and subglacial drainage systems exert key controls on glacier dynamics. However, due to their inaccessibility, they are still only poorly understood and more detailed observations are important, particularly to validate and tune physical models describing their dynamics. By creating ar...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press
2022
|
Subjects: | |
Online Access: | https://hdl.handle.net/20.500.11850/537322 https://doi.org/10.3929/ethz-b-000537322 |
id |
ftethz:oai:www.research-collection.ethz.ch:20.500.11850/537322 |
---|---|
record_format |
openpolar |
spelling |
ftethz:oai:www.research-collection.ethz.ch:20.500.11850/537322 2023-05-15T16:57:32+02:00 Characterising englacial R-channels using artificial moulins Pohle, Annegret Werder, Mauro Gräff, Dominik Farinotti, Daniel 2022-10 application/application/pdf https://hdl.handle.net/20.500.11850/537322 https://doi.org/10.3929/ethz-b-000537322 en eng Cambridge University Press info:eu-repo/semantics/altIdentifier/doi/10.1017/jog.2022.4 info:eu-repo/semantics/altIdentifier/wos/000768582400001 info:eu-repo/grantAgreement/ETHZ/ETH Grants/ETH-11 19-2 http://hdl.handle.net/20.500.11850/537322 doi:10.3929/ethz-b-000537322 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International CC-BY Journal of Glaciology, 68 (271) Glacier discharge Glacier hydrology Glaciological instruments and methods info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2022 ftethz https://doi.org/20.500.11850/537322 https://doi.org/10.3929/ethz-b-000537322 https://doi.org/10.1017/jog.2022.4 2023-02-13T01:13:30Z The englacial and subglacial drainage systems exert key controls on glacier dynamics. However, due to their inaccessibility, they are still only poorly understood and more detailed observations are important, particularly to validate and tune physical models describing their dynamics. By creating artificial glacier moulins – boreholes connected to the subglacial drainage system and supplied with water from surface streams – we present a novel method to monitor the evolution of an englacial hydrological system with high temporal resolution. Here, we use artificial moulins as representations for vertical, pressurised, englacial R-channels. From tracer and pressure measurements, we derive time series of the hydraulic gradient, discharge, flow speed and channel cross-sectional area. Using these, we compute the Darcy–Weisbach friction factor, obtaining values which increase from 0.1 to 13 within five days of channel evolution. Furthermore, we simulate the growth of the cross-sectional area using different temperature gradients. The comparison to our measurements largely supports the common assumption that the temperature follows the pressure melting point. The deviations from this behaviour are analysed using various heat transfer parameterisations to assess their applicability. Finally, we discuss how artificial moulins could be combined with glacier-wide tracer experiments to constrain parameters of subglacial drainage more precisely. ISSN:0022-1430 ISSN:1727-5652 Article in Journal/Newspaper Journal of Glaciology ETH Zürich Research Collection |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
topic |
Glacier discharge Glacier hydrology Glaciological instruments and methods |
spellingShingle |
Glacier discharge Glacier hydrology Glaciological instruments and methods Pohle, Annegret Werder, Mauro Gräff, Dominik Farinotti, Daniel Characterising englacial R-channels using artificial moulins |
topic_facet |
Glacier discharge Glacier hydrology Glaciological instruments and methods |
description |
The englacial and subglacial drainage systems exert key controls on glacier dynamics. However, due to their inaccessibility, they are still only poorly understood and more detailed observations are important, particularly to validate and tune physical models describing their dynamics. By creating artificial glacier moulins – boreholes connected to the subglacial drainage system and supplied with water from surface streams – we present a novel method to monitor the evolution of an englacial hydrological system with high temporal resolution. Here, we use artificial moulins as representations for vertical, pressurised, englacial R-channels. From tracer and pressure measurements, we derive time series of the hydraulic gradient, discharge, flow speed and channel cross-sectional area. Using these, we compute the Darcy–Weisbach friction factor, obtaining values which increase from 0.1 to 13 within five days of channel evolution. Furthermore, we simulate the growth of the cross-sectional area using different temperature gradients. The comparison to our measurements largely supports the common assumption that the temperature follows the pressure melting point. The deviations from this behaviour are analysed using various heat transfer parameterisations to assess their applicability. Finally, we discuss how artificial moulins could be combined with glacier-wide tracer experiments to constrain parameters of subglacial drainage more precisely. ISSN:0022-1430 ISSN:1727-5652 |
format |
Article in Journal/Newspaper |
author |
Pohle, Annegret Werder, Mauro Gräff, Dominik Farinotti, Daniel |
author_facet |
Pohle, Annegret Werder, Mauro Gräff, Dominik Farinotti, Daniel |
author_sort |
Pohle, Annegret |
title |
Characterising englacial R-channels using artificial moulins |
title_short |
Characterising englacial R-channels using artificial moulins |
title_full |
Characterising englacial R-channels using artificial moulins |
title_fullStr |
Characterising englacial R-channels using artificial moulins |
title_full_unstemmed |
Characterising englacial R-channels using artificial moulins |
title_sort |
characterising englacial r-channels using artificial moulins |
publisher |
Cambridge University Press |
publishDate |
2022 |
url |
https://hdl.handle.net/20.500.11850/537322 https://doi.org/10.3929/ethz-b-000537322 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology, 68 (271) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1017/jog.2022.4 info:eu-repo/semantics/altIdentifier/wos/000768582400001 info:eu-repo/grantAgreement/ETHZ/ETH Grants/ETH-11 19-2 http://hdl.handle.net/20.500.11850/537322 doi:10.3929/ethz-b-000537322 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/20.500.11850/537322 https://doi.org/10.3929/ethz-b-000537322 https://doi.org/10.1017/jog.2022.4 |
_version_ |
1766049095566229504 |