Ely, J. orcid.org/0000-0003-4007-1500, Clark, C.D., Ng, F.S.L. et al. (1 more author) (2017) Insights on the formation of longitudinal surface structures on ice sheets from analysis of their spacing, spatial distribution and relationship to ice thickness and flow. Journal of Geophysical Research: Earth Surface, 122 (4). pp. 961-972. ISSN 2169-9011
Abstract
Longitudinal surface structures (LSSs) are prevalent upon the ice streams, ice shelves and outlet glaciers of ice sheets. These features inform our understanding of past and present ice sheet behavior. However, consensus regarding their genesis has not been reached. Here we analyze 42,311 LSS segments mapped across Antarctica together with geophysical data to determine their morphological and glaciological properties. Most LSSs are spaced 450 to 1500 m apart, a distance positively correlated with the width of the ice flow unit on which they occur. The start points (upstream end locations) of LSSs have diverse ice thicknesses and velocities. The majority of LSSs occur where ice flow is converging or broadly parallel, and they are prominent at ice confluences. Some occur at slow-flowing ice stream onsets. Occasionally, LSSs relate to sudden variations in basal shear stress due to basal perturbations. From these observations, we argue that LSSs are the consequence of increased strain which occurs during the lateral compression and longitudinal extension of ice: (i) converging/flowing into a channel (this scenario characterizes most LSSs), (ii) at the onset of ice streaming, (iii) at flow unit confluence, and (iv) as ice flows over and around a basal perturbation.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © American Geophysical Union, 2017. This is an author produced version of a paper subsequently published in Journal of Geophysical Research: Earth Surface. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Social Sciences (Sheffield) > Department of Geography (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 31 Mar 2017 13:45 |
Last Modified: | 01 Jul 2017 15:04 |
Published Version: | https://doi.org/10.1002/2016JF004071 |
Status: | Published |
Publisher: | American Geophysical Union |
Refereed: | Yes |
Identification Number: | 10.1002/2016JF004071 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:114296 |