Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory
Analysis of a recent surge of Morsnevbreen, Svalbard, is used to test predictions of the enthalpy balance theory of surging. High-resolution time series of velocities, ice thickness and crevasse distribution allow key elements of the enthalpy (internal energy) budget to be quantified for different s...
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Cambridge University Press
2019
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ftdoajarticles:oai:doaj.org/article:dc92a2acb06a47f48295b2c01414b716 2023-05-15T15:08:06+02:00 Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory Douglas I. Benn Robert L. Jones Adrian Luckman Johannes J. Fürst Ian Hewitt Christian Sommer 2019-10-01T00:00:00Z https://doi.org/10.1017/jog.2019.63 https://doaj.org/article/dc92a2acb06a47f48295b2c01414b716 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143019000637/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2019.63 0022-1430 1727-5652 https://doaj.org/article/dc92a2acb06a47f48295b2c01414b716 Journal of Glaciology, Vol 65, Pp 717-731 (2019) Arctic glaciology glacier surges ice dynamics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2019 ftdoajarticles https://doi.org/10.1017/jog.2019.63 2023-03-12T01:30:57Z Analysis of a recent surge of Morsnevbreen, Svalbard, is used to test predictions of the enthalpy balance theory of surging. High-resolution time series of velocities, ice thickness and crevasse distribution allow key elements of the enthalpy (internal energy) budget to be quantified for different stages of the surge cycle. During quiescence (1936–1990), velocities were very low, and geothermal heat slowly built-up enthalpy at the bed. Measurable mass transfer and frictional heating began in 1990–2010, then positive frictional heating-velocity feedbacks caused gradual acceleration from 2010 to 2015. Rapid acceleration occurred in summer 2016, when extensive crevassing and positive air temperatures allowed significant surface to bed drainage. The surge front reached the terminus in October 2016, coincident with a drop in velocities. Ice plumes in the fjord are interpreted as discharge of large volumes of supercooled water from the bed. Surge termination was prolonged, however, indicating persistence of an inefficient drainage system. The observations closely match predictions of the theory, particularly build-up of enthalpy from geothermal and frictional heat, and surface meltwater, and the concomitant changes in ice-surface elevation and velocity. Additional characteristics of the surge reflect spatial processes not represented in the model, but can be explained with respect to enthalpy gradients. Article in Journal/Newspaper Arctic glacier Journal of Glaciology Svalbard Directory of Open Access Journals: DOAJ Articles Arctic Svalbard Journal of Glaciology 65 253 717 731 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic glaciology glacier surges ice dynamics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Arctic glaciology glacier surges ice dynamics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Douglas I. Benn Robert L. Jones Adrian Luckman Johannes J. Fürst Ian Hewitt Christian Sommer Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
topic_facet |
Arctic glaciology glacier surges ice dynamics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Analysis of a recent surge of Morsnevbreen, Svalbard, is used to test predictions of the enthalpy balance theory of surging. High-resolution time series of velocities, ice thickness and crevasse distribution allow key elements of the enthalpy (internal energy) budget to be quantified for different stages of the surge cycle. During quiescence (1936–1990), velocities were very low, and geothermal heat slowly built-up enthalpy at the bed. Measurable mass transfer and frictional heating began in 1990–2010, then positive frictional heating-velocity feedbacks caused gradual acceleration from 2010 to 2015. Rapid acceleration occurred in summer 2016, when extensive crevassing and positive air temperatures allowed significant surface to bed drainage. The surge front reached the terminus in October 2016, coincident with a drop in velocities. Ice plumes in the fjord are interpreted as discharge of large volumes of supercooled water from the bed. Surge termination was prolonged, however, indicating persistence of an inefficient drainage system. The observations closely match predictions of the theory, particularly build-up of enthalpy from geothermal and frictional heat, and surface meltwater, and the concomitant changes in ice-surface elevation and velocity. Additional characteristics of the surge reflect spatial processes not represented in the model, but can be explained with respect to enthalpy gradients. |
format |
Article in Journal/Newspaper |
author |
Douglas I. Benn Robert L. Jones Adrian Luckman Johannes J. Fürst Ian Hewitt Christian Sommer |
author_facet |
Douglas I. Benn Robert L. Jones Adrian Luckman Johannes J. Fürst Ian Hewitt Christian Sommer |
author_sort |
Douglas I. Benn |
title |
Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
title_short |
Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
title_full |
Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
title_fullStr |
Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
title_full_unstemmed |
Mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
title_sort |
mass and enthalpy budget evolution during the surge of a polythermal glacier: a test of theory |
publisher |
Cambridge University Press |
publishDate |
2019 |
url |
https://doi.org/10.1017/jog.2019.63 https://doaj.org/article/dc92a2acb06a47f48295b2c01414b716 |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
Arctic glacier Journal of Glaciology Svalbard |
genre_facet |
Arctic glacier Journal of Glaciology Svalbard |
op_source |
Journal of Glaciology, Vol 65, Pp 717-731 (2019) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143019000637/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2019.63 0022-1430 1727-5652 https://doaj.org/article/dc92a2acb06a47f48295b2c01414b716 |
op_doi |
https://doi.org/10.1017/jog.2019.63 |
container_title |
Journal of Glaciology |
container_volume |
65 |
container_issue |
253 |
container_start_page |
717 |
op_container_end_page |
731 |
_version_ |
1766339518768611328 |