Eintrag weiter verarbeiten
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland
Gespeichert in:
| Zeitschriftentitel: | Journal of Glaciology |
|---|---|
| Personen und Körperschaften: | |
| In: | Journal of Glaciology, 45, 1999, 150, S. 219-230 |
| Format: | E-Article |
| Sprache: | Englisch |
| veröffentlicht: |
International Glaciological Society
|
| Schlagwörter: |
| author_facet |
Gudmundsson, G. Hilmar Gudmundsson, G. Hilmar |
|---|---|
| author |
Gudmundsson, G. Hilmar |
| spellingShingle |
Gudmundsson, G. Hilmar Journal of Glaciology A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland Earth-Surface Processes |
| author_sort |
gudmundsson, g. hilmar |
| spelling |
Gudmundsson, G. Hilmar 0022-1430 1727-5652 International Glaciological Society Earth-Surface Processes http://dx.doi.org/10.3189/s0022143000001726 <jats:title>Abstract</jats:title><jats:p>With the use of a numerical three-dimensional (3-D) model the flow dynamics of the confluence area of Unteraargletscher, Bernese Alps, Switzerland, are studied. Previous predictions, based on conceptual two-dimensional models, about flow characteristics at confluence areas are tested against results from the fully 3-D model. Measured winter velocities are used for model verification. Despite some consistent systematic differences, good overall agreement between measured and calculated surface velocities is obtained. The calculated vertical strain-rate variation with depth is in good agreement with available measurements from boreholes. The ice is found to be almost three times stiffer than standard estimates of rheological parameters for glacier ice would predict. The model predicts a complicated yet realistic pattern of vertical velocity variation along the surface. The most noticeable features of the vertical velocity distribution across the surface are listed, and their relation to topographic surface undulations and the overall dynamics of the confluence discussed. In accordance with previous results from analytical models, a strongly localized surface trough and a concomitant negative (downward orientation) vertical velocity anomaly develop at the junction point. Although depth-integrated strain rates are positive (extension), the basal layer is compressed vertically. The ice-cored medial moraine is formed by differential ablation. The flow mechanics of the confluence area play only an indirect role, by enabling transfer of debris-covered marginal ice towards the confluence center. In the absence of differential ablation, an elongated surface depression would be formed in the down-glacier direction from the junction point instead of an elevated ice-cored medial moraine.</jats:p> A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland Journal of Glaciology |
| doi_str_mv |
10.3189/s0022143000001726 |
| facet_avail |
Online Free |
| finc_class_facet |
Geologie und Paläontologie Geographie |
| format |
ElectronicArticle |
| fullrecord |
blob:ai-49-aHR0cDovL2R4LmRvaS5vcmcvMTAuMzE4OS9zMDAyMjE0MzAwMDAwMTcyNg |
| id |
ai-49-aHR0cDovL2R4LmRvaS5vcmcvMTAuMzE4OS9zMDAyMjE0MzAwMDAwMTcyNg |
| institution |
DE-Gla1 DE-Zi4 DE-15 DE-Pl11 DE-Rs1 DE-105 DE-14 DE-Ch1 DE-L229 DE-D275 DE-Bn3 DE-Brt1 DE-D161 DE-Zwi2 |
| imprint |
International Glaciological Society, 1999 |
| imprint_str_mv |
International Glaciological Society, 1999 |
| issn |
0022-1430 1727-5652 |
| issn_str_mv |
0022-1430 1727-5652 |
| language |
English |
| mega_collection |
International Glaciological Society (CrossRef) |
| match_str |
gudmundsson1999athreedimensionalnumericalmodeloftheconfluenceareaofunteraargletscherbernesealpsswitzerland |
| publishDateSort |
1999 |
| publisher |
International Glaciological Society |
| recordtype |
ai |
| record_format |
ai |
| series |
Journal of Glaciology |
| source_id |
49 |
| title |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_unstemmed |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_full |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_fullStr |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_full_unstemmed |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_short |
A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_sort |
a three-dimensional numerical model of the confluence area of unteraargletscher, bernese alps, switzerland |
| topic |
Earth-Surface Processes |
| url |
http://dx.doi.org/10.3189/s0022143000001726 |
| publishDate |
1999 |
| physical |
219-230 |
| description |
<jats:title>Abstract</jats:title><jats:p>With the use of a numerical three-dimensional (3-D) model the flow dynamics of the confluence area of Unteraargletscher, Bernese Alps, Switzerland, are studied. Previous predictions, based on conceptual two-dimensional models, about flow characteristics at confluence areas are tested against results from the fully 3-D model. Measured winter velocities are used for model verification. Despite some consistent systematic differences, good overall agreement between measured and calculated surface velocities is obtained. The calculated vertical strain-rate variation with depth is in good agreement with available measurements from boreholes. The ice is found to be almost three times stiffer than standard estimates of rheological parameters for glacier ice would predict. The model predicts a complicated yet realistic pattern of vertical velocity variation along the surface. The most noticeable features of the vertical velocity distribution across the surface are listed, and their relation to topographic surface undulations and the overall dynamics of the confluence discussed. In accordance with previous results from analytical models, a strongly localized surface trough and a concomitant negative (downward orientation) vertical velocity anomaly develop at the junction point. Although depth-integrated strain rates are positive (extension), the basal layer is compressed vertically. The ice-cored medial moraine is formed by differential ablation. The flow mechanics of the confluence area play only an indirect role, by enabling transfer of debris-covered marginal ice towards the confluence center. In the absence of differential ablation, an elongated surface depression would be formed in the down-glacier direction from the junction point instead of an elevated ice-cored medial moraine.</jats:p> |
| container_issue |
150 |
| container_start_page |
219 |
| container_title |
Journal of Glaciology |
| container_volume |
45 |
| format_de105 |
Article, E-Article |
| format_de14 |
Article, E-Article |
| format_de15 |
Article, E-Article |
| format_de520 |
Article, E-Article |
| format_de540 |
Article, E-Article |
| format_dech1 |
Article, E-Article |
| format_ded117 |
Article, E-Article |
| format_degla1 |
E-Article |
| format_del152 |
Buch |
| format_del189 |
Article, E-Article |
| format_dezi4 |
Article |
| format_dezwi2 |
Article, E-Article |
| format_finc |
Article, E-Article |
| format_nrw |
Article, E-Article |
| _version_ |
1792329971691159556 |
| geogr_code |
not assigned |
| last_indexed |
2024-03-01T13:17:40.434Z |
| geogr_code_person |
not assigned |
| openURL |
url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&ctx_enc=info%3Aofi%2Fenc%3AUTF-8&rfr_id=info%3Asid%2Fvufind.svn.sourceforge.net%3Agenerator&rft.title=A+three-dimensional+numerical+model+of+the+confluence+area+of+Unteraargletscher%2C+Bernese+Alps%2C+Switzerland&rft.date=1999-01-01&genre=article&issn=1727-5652&volume=45&issue=150&spage=219&epage=230&pages=219-230&jtitle=Journal+of+Glaciology&atitle=A+three-dimensional+numerical+model+of+the+confluence+area+of+Unteraargletscher%2C+Bernese+Alps%2C+Switzerland&aulast=Gudmundsson&aufirst=G.+Hilmar&rft_id=info%3Adoi%2F10.3189%2Fs0022143000001726&rft.language%5B0%5D=eng |
| SOLR | |
| _version_ | 1792329971691159556 |
| author | Gudmundsson, G. Hilmar |
| author_facet | Gudmundsson, G. Hilmar, Gudmundsson, G. Hilmar |
| author_sort | gudmundsson, g. hilmar |
| container_issue | 150 |
| container_start_page | 219 |
| container_title | Journal of Glaciology |
| container_volume | 45 |
| description | <jats:title>Abstract</jats:title><jats:p>With the use of a numerical three-dimensional (3-D) model the flow dynamics of the confluence area of Unteraargletscher, Bernese Alps, Switzerland, are studied. Previous predictions, based on conceptual two-dimensional models, about flow characteristics at confluence areas are tested against results from the fully 3-D model. Measured winter velocities are used for model verification. Despite some consistent systematic differences, good overall agreement between measured and calculated surface velocities is obtained. The calculated vertical strain-rate variation with depth is in good agreement with available measurements from boreholes. The ice is found to be almost three times stiffer than standard estimates of rheological parameters for glacier ice would predict. The model predicts a complicated yet realistic pattern of vertical velocity variation along the surface. The most noticeable features of the vertical velocity distribution across the surface are listed, and their relation to topographic surface undulations and the overall dynamics of the confluence discussed. In accordance with previous results from analytical models, a strongly localized surface trough and a concomitant negative (downward orientation) vertical velocity anomaly develop at the junction point. Although depth-integrated strain rates are positive (extension), the basal layer is compressed vertically. The ice-cored medial moraine is formed by differential ablation. The flow mechanics of the confluence area play only an indirect role, by enabling transfer of debris-covered marginal ice towards the confluence center. In the absence of differential ablation, an elongated surface depression would be formed in the down-glacier direction from the junction point instead of an elevated ice-cored medial moraine.</jats:p> |
| doi_str_mv | 10.3189/s0022143000001726 |
| facet_avail | Online, Free |
| finc_class_facet | Geologie und Paläontologie, Geographie |
| format | ElectronicArticle |
| format_de105 | Article, E-Article |
| format_de14 | Article, E-Article |
| format_de15 | Article, E-Article |
| format_de520 | Article, E-Article |
| format_de540 | Article, E-Article |
| format_dech1 | Article, E-Article |
| format_ded117 | Article, E-Article |
| format_degla1 | E-Article |
| format_del152 | Buch |
| format_del189 | Article, E-Article |
| format_dezi4 | Article |
| format_dezwi2 | Article, E-Article |
| format_finc | Article, E-Article |
| format_nrw | Article, E-Article |
| geogr_code | not assigned |
| geogr_code_person | not assigned |
| id | ai-49-aHR0cDovL2R4LmRvaS5vcmcvMTAuMzE4OS9zMDAyMjE0MzAwMDAwMTcyNg |
| imprint | International Glaciological Society, 1999 |
| imprint_str_mv | International Glaciological Society, 1999 |
| institution | DE-Gla1, DE-Zi4, DE-15, DE-Pl11, DE-Rs1, DE-105, DE-14, DE-Ch1, DE-L229, DE-D275, DE-Bn3, DE-Brt1, DE-D161, DE-Zwi2 |
| issn | 0022-1430, 1727-5652 |
| issn_str_mv | 0022-1430, 1727-5652 |
| language | English |
| last_indexed | 2024-03-01T13:17:40.434Z |
| match_str | gudmundsson1999athreedimensionalnumericalmodeloftheconfluenceareaofunteraargletscherbernesealpsswitzerland |
| mega_collection | International Glaciological Society (CrossRef) |
| physical | 219-230 |
| publishDate | 1999 |
| publishDateSort | 1999 |
| publisher | International Glaciological Society |
| record_format | ai |
| recordtype | ai |
| series | Journal of Glaciology |
| source_id | 49 |
| spelling | Gudmundsson, G. Hilmar 0022-1430 1727-5652 International Glaciological Society Earth-Surface Processes http://dx.doi.org/10.3189/s0022143000001726 <jats:title>Abstract</jats:title><jats:p>With the use of a numerical three-dimensional (3-D) model the flow dynamics of the confluence area of Unteraargletscher, Bernese Alps, Switzerland, are studied. Previous predictions, based on conceptual two-dimensional models, about flow characteristics at confluence areas are tested against results from the fully 3-D model. Measured winter velocities are used for model verification. Despite some consistent systematic differences, good overall agreement between measured and calculated surface velocities is obtained. The calculated vertical strain-rate variation with depth is in good agreement with available measurements from boreholes. The ice is found to be almost three times stiffer than standard estimates of rheological parameters for glacier ice would predict. The model predicts a complicated yet realistic pattern of vertical velocity variation along the surface. The most noticeable features of the vertical velocity distribution across the surface are listed, and their relation to topographic surface undulations and the overall dynamics of the confluence discussed. In accordance with previous results from analytical models, a strongly localized surface trough and a concomitant negative (downward orientation) vertical velocity anomaly develop at the junction point. Although depth-integrated strain rates are positive (extension), the basal layer is compressed vertically. The ice-cored medial moraine is formed by differential ablation. The flow mechanics of the confluence area play only an indirect role, by enabling transfer of debris-covered marginal ice towards the confluence center. In the absence of differential ablation, an elongated surface depression would be formed in the down-glacier direction from the junction point instead of an elevated ice-cored medial moraine.</jats:p> A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland Journal of Glaciology |
| spellingShingle | Gudmundsson, G. Hilmar, Journal of Glaciology, A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland, Earth-Surface Processes |
| title | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_full | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_fullStr | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_full_unstemmed | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_short | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| title_sort | a three-dimensional numerical model of the confluence area of unteraargletscher, bernese alps, switzerland |
| title_unstemmed | A three-dimensional numerical model of the confluence area of Unteraargletscher, Bernese Alps, Switzerland |
| topic | Earth-Surface Processes |
| url | http://dx.doi.org/10.3189/s0022143000001726 |