Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007
ABSTRACT Glaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass b...
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Language: | English |
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2016.55 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000551 |
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crcambridgeupr:10.1017/jog.2016.55 2024-06-23T07:53:03+00:00 Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 POPE, ALLEN WILLIS, IAN C. PÁLSSON, FINNUR ARNOLD, NEIL S. REES, W. GARETH BJÖRNSSON, HELGI GREY, LAUREN 2016 http://dx.doi.org/10.1017/jog.2016.55 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000551 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 62, issue 233, page 497-511 ISSN 0022-1430 1727-5652 journal-article 2016 crcambridgeupr https://doi.org/10.1017/jog.2016.55 2024-06-12T04:04:58Z ABSTRACT Glaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses and a mass-balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull's outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e. mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate or degree-day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge. Article in Journal/Newspaper glacier Ice cap Iceland Journal of Glaciology Langjökull Cambridge University Press Langjökull ENVELOPE(-20.145,-20.145,64.654,64.654) Journal of Glaciology 62 233 497 511 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
ABSTRACT Glaciers and ice caps around the world are changing quickly, with surge-type behaviour superimposed upon climatic forcing. Here, we study Iceland's second largest ice cap, Langjökull, which has both surge- and non-surge-type outlets. By differencing elevation change with surface mass balance, we estimate the contribution of ice dynamics to elevation change. We use DEMs, in situ stake measurements, regional reanalyses and a mass-balance model to calculate the vertical ice velocity. Thus, we not only compare the geodetic, modelled and glaciological mass balances, but also map spatial variations in glacier dynamics. Maps of emergence and submergence velocity successfully highlight the 1998 surge and subsequent quiescence of one of Langjökull's outlets by visualizing both source and sink areas. In addition to observing the extent of traditional surge behaviour (i.e. mass transfer from the accumulation area to the ablation area followed by recharge of the source area), we see peripheral areas where the surge impinged upon an adjacent ridge and subsequently retreated. While mass balances are largely in good agreement, discrepancies between modelled and geodetic mass balance may be explained by inaccurate estimates of precipitation, saturated adiabatic lapse rate or degree-day factors. Nevertheless, the study was ultimately able to investigate dynamic surge behaviour in the absence of in situ measurements during the surge. |
format |
Article in Journal/Newspaper |
author |
POPE, ALLEN WILLIS, IAN C. PÁLSSON, FINNUR ARNOLD, NEIL S. REES, W. GARETH BJÖRNSSON, HELGI GREY, LAUREN |
spellingShingle |
POPE, ALLEN WILLIS, IAN C. PÁLSSON, FINNUR ARNOLD, NEIL S. REES, W. GARETH BJÖRNSSON, HELGI GREY, LAUREN Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
author_facet |
POPE, ALLEN WILLIS, IAN C. PÁLSSON, FINNUR ARNOLD, NEIL S. REES, W. GARETH BJÖRNSSON, HELGI GREY, LAUREN |
author_sort |
POPE, ALLEN |
title |
Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
title_short |
Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
title_full |
Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
title_fullStr |
Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
title_full_unstemmed |
Elevation change, mass balance, dynamics and surging of Langjökull, Iceland from 1997 to 2007 |
title_sort |
elevation change, mass balance, dynamics and surging of langjökull, iceland from 1997 to 2007 |
publisher |
Cambridge University Press (CUP) |
publishDate |
2016 |
url |
http://dx.doi.org/10.1017/jog.2016.55 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000551 |
long_lat |
ENVELOPE(-20.145,-20.145,64.654,64.654) |
geographic |
Langjökull |
geographic_facet |
Langjökull |
genre |
glacier Ice cap Iceland Journal of Glaciology Langjökull |
genre_facet |
glacier Ice cap Iceland Journal of Glaciology Langjökull |
op_source |
Journal of Glaciology volume 62, issue 233, page 497-511 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2016.55 |
container_title |
Journal of Glaciology |
container_volume |
62 |
container_issue |
233 |
container_start_page |
497 |
op_container_end_page |
511 |
_version_ |
1802644531577880576 |