Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach
Ice covers a significant part of the Earth’s surface and is one key component of the global climate system. A thorough understanding of ice flow is crucial for modeling the response of ice sheets to past and upcoming climate changes. Glen’s law, a experimentally derived exponential relationship betw...
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Universitätsbibliothek Heidelberg
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ftawi:oai:epic.awi.de:35578 2023-05-15T13:40:26+02:00 Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach Binder, Tobias 2014 application/pdf https://epic.awi.de/id/eprint/35578/ https://epic.awi.de/id/eprint/35578/1/BinderDissertation_final.pdf https://hdl.handle.net/10013/epic.43559 https://hdl.handle.net/10013/epic.43559.d001 unknown Universitätsbibliothek Heidelberg https://epic.awi.de/id/eprint/35578/1/BinderDissertation_final.pdf https://hdl.handle.net/10013/epic.43559.d001 Binder, T. (2014) Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach , PhD thesis, Universität Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR). hdl:10013/epic.43559 EPIC3Universitätsbibliothek Heidelberg, 141 p. Thesis notRev 2014 ftawi 2021-12-24T15:39:32Z Ice covers a significant part of the Earth’s surface and is one key component of the global climate system. A thorough understanding of ice flow is crucial for modeling the response of ice sheets to past and upcoming climate changes. Glen’s law, a experimentally derived exponential relationship between stress and strain rate, is usually applied. However, it does not adequately capture microstructural changes observed for high total shear strains and long time scales which cannot be reproduced by laboratory experiments. Deep ice cores provide insights into the natural evolution of microstructure (grain boundary networks). Large sets of sublimation groove images, mapping grain boundaries in high resolution, are available along the EDML (East Antarctica) and NEEM (Greenland) ice cores. A digital image processing approach has been developed to derive grain size, grain shape, shape of grain boundaries, and density of sub-grain boundaries in a consistent way. An automatic assignment to c-axes orientation measurements allows estimating the error of calculated parameters. Depth profiles along both ice cores are presented and interpreted based on variations in impurity content, temperature differences, and involved time scales. Furthermore, the presence of effective negative pressures caused by air bubbles and clathrate hydrates is taken into account. Thesis Antarc* Antarctica East Antarctica Greenland Greenland ice cores Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) East Antarctica Greenland |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Ice covers a significant part of the Earth’s surface and is one key component of the global climate system. A thorough understanding of ice flow is crucial for modeling the response of ice sheets to past and upcoming climate changes. Glen’s law, a experimentally derived exponential relationship between stress and strain rate, is usually applied. However, it does not adequately capture microstructural changes observed for high total shear strains and long time scales which cannot be reproduced by laboratory experiments. Deep ice cores provide insights into the natural evolution of microstructure (grain boundary networks). Large sets of sublimation groove images, mapping grain boundaries in high resolution, are available along the EDML (East Antarctica) and NEEM (Greenland) ice cores. A digital image processing approach has been developed to derive grain size, grain shape, shape of grain boundaries, and density of sub-grain boundaries in a consistent way. An automatic assignment to c-axes orientation measurements allows estimating the error of calculated parameters. Depth profiles along both ice cores are presented and interpreted based on variations in impurity content, temperature differences, and involved time scales. Furthermore, the presence of effective negative pressures caused by air bubbles and clathrate hydrates is taken into account. |
format |
Thesis |
author |
Binder, Tobias |
spellingShingle |
Binder, Tobias Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
author_facet |
Binder, Tobias |
author_sort |
Binder, Tobias |
title |
Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
title_short |
Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
title_full |
Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
title_fullStr |
Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
title_full_unstemmed |
Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach |
title_sort |
measurements of grain boundary networks in deep polar ice cores - a digital image processing approach |
publisher |
Universitätsbibliothek Heidelberg |
publishDate |
2014 |
url |
https://epic.awi.de/id/eprint/35578/ https://epic.awi.de/id/eprint/35578/1/BinderDissertation_final.pdf https://hdl.handle.net/10013/epic.43559 https://hdl.handle.net/10013/epic.43559.d001 |
geographic |
East Antarctica Greenland |
geographic_facet |
East Antarctica Greenland |
genre |
Antarc* Antarctica East Antarctica Greenland Greenland ice cores |
genre_facet |
Antarc* Antarctica East Antarctica Greenland Greenland ice cores |
op_source |
EPIC3Universitätsbibliothek Heidelberg, 141 p. |
op_relation |
https://epic.awi.de/id/eprint/35578/1/BinderDissertation_final.pdf https://hdl.handle.net/10013/epic.43559.d001 Binder, T. (2014) Measurements of grain boundary networks in deep polar ice cores - A digital image processing approach , PhD thesis, Universität Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen (IWR). hdl:10013/epic.43559 |
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1766133996762169344 |