Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet.
With continued warming regional surface air temperatures around the Artic in recent decades, there is growing importance in understanding how ice sheet dynamics interact with a shifting global climate system. This research investigates the spatial variability of sub-glacial hydrology under land term...
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Uppsala universitet, Institutionen för geovetenskaper
2016
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ftuppsalauniv:oai:DiVA.org:uu-305434 2023-05-15T16:21:32+02:00 Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. Applicering av GIS för att undersöka rumsligvariabilitet av sub-glacial hydrologi under istäckenpå land i det västra Grönländska istäcket. Samuel, Welsh 2016 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-305434 eng eng Uppsala universitet, Institutionen för geovetenskaper Examensarbete vid Institutionen för geovetenskaper, 1650-6553 383 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-305434 info:eu-repo/semantics/openAccess Hydraulic potential Greenland GIS sub-glacial hydrological network ice sheet dynamics Hydraulisk potential Grönländ sub-glacial hydrologi istäckesdynamik Physical Geography Naturgeografi Student thesis info:eu-repo/semantics/bachelorThesis text 2016 ftuppsalauniv 2023-02-23T21:46:44Z With continued warming regional surface air temperatures around the Artic in recent decades, there is growing importance in understanding how ice sheet dynamics interact with a shifting global climate system. This research investigates the spatial variability of sub-glacial hydrology under land terminating ice sheets in Western GrIS, when applying varying overburden ice pressures within Shreve’s (1972) hydraulic potential equation. The application of ArcGIS is used with adjusted k-values in the equation to route hydrological network systems under the ice sheet and help identify the processes taking place within the sub-glacial system. With focus on processes such as water piracy, we are able illustrate the effects that water at the base can have on ice sheet behaviors. i.e. velocity and mas balance. The findings conclude that the ice sheet is operating under conditions at its base with a k-value somewhere within the range of 0.9 to 1.1. This assumption is based on comparisons between modelled pro-glacial output with observed data taken from studies by Mikkelsen et al. (2014) and Smith et al. (2015), using input melt data at the surface (Lindback et. al., 2015). At this level of hydraulic potential, water piracy is effectively changing the course pathways of the hydrological network and therefore manipulating the size and shape of the sub-glacial catchments. As a result, discharge may leave the glacier from a different location than what would be assumed. Identifying the location and volume of water under particular ice sheets, compared to neighboring ice sheets, can be used to explain spatial and temporal differences in ice sheet characteristics. Such research is important in understanding both environmental and socio-economic implications at local to global scale. Although the application of GIS methodology is extremely useful is producing such results, it must be recognised that a high level of uncertainty and error exists in the data results. Temperatur kan ha en särskilt stark inverkan på hur istäcken ... Bachelor Thesis glacier Greenland Ice Sheet Uppsala University: Publications (DiVA) Greenland Mikkelsen ENVELOPE(-67.129,-67.129,-68.749,-68.749) Västra ENVELOPE(21.867,21.867,66.817,66.817) |
institution |
Open Polar |
collection |
Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
Hydraulic potential Greenland GIS sub-glacial hydrological network ice sheet dynamics Hydraulisk potential Grönländ sub-glacial hydrologi istäckesdynamik Physical Geography Naturgeografi |
spellingShingle |
Hydraulic potential Greenland GIS sub-glacial hydrological network ice sheet dynamics Hydraulisk potential Grönländ sub-glacial hydrologi istäckesdynamik Physical Geography Naturgeografi Samuel, Welsh Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
topic_facet |
Hydraulic potential Greenland GIS sub-glacial hydrological network ice sheet dynamics Hydraulisk potential Grönländ sub-glacial hydrologi istäckesdynamik Physical Geography Naturgeografi |
description |
With continued warming regional surface air temperatures around the Artic in recent decades, there is growing importance in understanding how ice sheet dynamics interact with a shifting global climate system. This research investigates the spatial variability of sub-glacial hydrology under land terminating ice sheets in Western GrIS, when applying varying overburden ice pressures within Shreve’s (1972) hydraulic potential equation. The application of ArcGIS is used with adjusted k-values in the equation to route hydrological network systems under the ice sheet and help identify the processes taking place within the sub-glacial system. With focus on processes such as water piracy, we are able illustrate the effects that water at the base can have on ice sheet behaviors. i.e. velocity and mas balance. The findings conclude that the ice sheet is operating under conditions at its base with a k-value somewhere within the range of 0.9 to 1.1. This assumption is based on comparisons between modelled pro-glacial output with observed data taken from studies by Mikkelsen et al. (2014) and Smith et al. (2015), using input melt data at the surface (Lindback et. al., 2015). At this level of hydraulic potential, water piracy is effectively changing the course pathways of the hydrological network and therefore manipulating the size and shape of the sub-glacial catchments. As a result, discharge may leave the glacier from a different location than what would be assumed. Identifying the location and volume of water under particular ice sheets, compared to neighboring ice sheets, can be used to explain spatial and temporal differences in ice sheet characteristics. Such research is important in understanding both environmental and socio-economic implications at local to global scale. Although the application of GIS methodology is extremely useful is producing such results, it must be recognised that a high level of uncertainty and error exists in the data results. Temperatur kan ha en särskilt stark inverkan på hur istäcken ... |
format |
Bachelor Thesis |
author |
Samuel, Welsh |
author_facet |
Samuel, Welsh |
author_sort |
Samuel, Welsh |
title |
Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
title_short |
Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
title_full |
Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
title_fullStr |
Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
title_full_unstemmed |
Applying GIS to Investigate the Spatial Variability of Sub-Glacial Hydrology under Land Terminating Ice Sheets in Western Greenland Ice Sheet. |
title_sort |
applying gis to investigate the spatial variability of sub-glacial hydrology under land terminating ice sheets in western greenland ice sheet. |
publisher |
Uppsala universitet, Institutionen för geovetenskaper |
publishDate |
2016 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-305434 |
long_lat |
ENVELOPE(-67.129,-67.129,-68.749,-68.749) ENVELOPE(21.867,21.867,66.817,66.817) |
geographic |
Greenland Mikkelsen Västra |
geographic_facet |
Greenland Mikkelsen Västra |
genre |
glacier Greenland Ice Sheet |
genre_facet |
glacier Greenland Ice Sheet |
op_relation |
Examensarbete vid Institutionen för geovetenskaper, 1650-6553 383 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-305434 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766009531766145024 |