Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard
A firn aquifer is a type of englacial water storage that forms when surface meltwater fills up the pore space in porous firn. If the retention time exceeds one year the feature is regarded as perennial. The melt and accumulation rates as well as the available pore space determine the formation and e...
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Uppsala universitet, Institutionen för geovetenskaper
2019
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ftuppsalauniv:oai:DiVA.org:uu-384176 2023-05-15T16:30:32+02:00 Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard Rumsliga och tidsmässiga variationer i en flerårig firnakvifer på Lomonosovfonna, Svalbard Hawrylak, Monika Nilsson, Emma 2019 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384176 eng eng Uppsala universitet, Institutionen för geovetenskaper http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384176 info:eu-repo/semantics/openAccess perennial firn aquifer ground penetrating radar Svalbard Lomonosovfonna flerårig firnakvifer georadar Earth and Related Environmental Sciences Geovetenskap och miljövetenskap Student thesis info:eu-repo/semantics/bachelorThesis text 2019 ftuppsalauniv 2023-02-23T21:49:53Z A firn aquifer is a type of englacial water storage that forms when surface meltwater fills up the pore space in porous firn. If the retention time exceeds one year the feature is regarded as perennial. The melt and accumulation rates as well as the available pore space determine the formation and extent of the firn aquifer. Flow of water within the aquifer caused by gradients in hydraulic potential leads to redistribution of water and consequently to a change in the level of the water table. This thesis focuses on a perennial firn aquifer on the Lomonosovfonna ice field on Svalbard. Spatial and temporal variations in the depth to the water table as well as variations in reflectivity strength of the water table are analysed using data from ground penetrating radar surveys along with MATLAB and ArcGIS software tools. The results show a clear connection between surface topography, steepness of its slopes and depth to the water table. It is also proved that the depth varies between different years. During the four years of study, the water table in the area rose closer to the surface. The results also show that the reflections from the top of the water table are stronger and more frequently detected in areas with gentler water table slopes. A similar correlation is true for the surface topography slope, where a gentler slope shows a stronger reflectivity. The results support the previous research done on Holtedahlfonna’s aquifer on Svalbard as well as aquifers on Greenland. En firnakvifer är en typ av englacial vattenlagring som formas när smältvatten från en glaciärs yta fyller upp porutrymmen i porös firn. När retentionstiden överskrider ett år betraktas akviferen som flerårig. Smält- och ackumulationshastigheten samt det tillgängliga porutrymmet avgör bildningen och utsträckningen av akviferen. Vattenflödet i akviferen orsakad av gradienter i hydraulisk potential leder till omfördelning av vattnet och därmed till förändringar i vattenytans nivå. Denna uppsats fokuserar på en akvifer på isfältet Lomonosovfonna ... Bachelor Thesis Greenland Svalbard Uppsala University: Publications (DiVA) Greenland Lomonosovfonna ENVELOPE(17.663,17.663,78.774,78.774) Svalbard |
institution |
Open Polar |
collection |
Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
perennial firn aquifer ground penetrating radar Svalbard Lomonosovfonna flerårig firnakvifer georadar Earth and Related Environmental Sciences Geovetenskap och miljövetenskap |
spellingShingle |
perennial firn aquifer ground penetrating radar Svalbard Lomonosovfonna flerårig firnakvifer georadar Earth and Related Environmental Sciences Geovetenskap och miljövetenskap Hawrylak, Monika Nilsson, Emma Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
topic_facet |
perennial firn aquifer ground penetrating radar Svalbard Lomonosovfonna flerårig firnakvifer georadar Earth and Related Environmental Sciences Geovetenskap och miljövetenskap |
description |
A firn aquifer is a type of englacial water storage that forms when surface meltwater fills up the pore space in porous firn. If the retention time exceeds one year the feature is regarded as perennial. The melt and accumulation rates as well as the available pore space determine the formation and extent of the firn aquifer. Flow of water within the aquifer caused by gradients in hydraulic potential leads to redistribution of water and consequently to a change in the level of the water table. This thesis focuses on a perennial firn aquifer on the Lomonosovfonna ice field on Svalbard. Spatial and temporal variations in the depth to the water table as well as variations in reflectivity strength of the water table are analysed using data from ground penetrating radar surveys along with MATLAB and ArcGIS software tools. The results show a clear connection between surface topography, steepness of its slopes and depth to the water table. It is also proved that the depth varies between different years. During the four years of study, the water table in the area rose closer to the surface. The results also show that the reflections from the top of the water table are stronger and more frequently detected in areas with gentler water table slopes. A similar correlation is true for the surface topography slope, where a gentler slope shows a stronger reflectivity. The results support the previous research done on Holtedahlfonna’s aquifer on Svalbard as well as aquifers on Greenland. En firnakvifer är en typ av englacial vattenlagring som formas när smältvatten från en glaciärs yta fyller upp porutrymmen i porös firn. När retentionstiden överskrider ett år betraktas akviferen som flerårig. Smält- och ackumulationshastigheten samt det tillgängliga porutrymmet avgör bildningen och utsträckningen av akviferen. Vattenflödet i akviferen orsakad av gradienter i hydraulisk potential leder till omfördelning av vattnet och därmed till förändringar i vattenytans nivå. Denna uppsats fokuserar på en akvifer på isfältet Lomonosovfonna ... |
format |
Bachelor Thesis |
author |
Hawrylak, Monika Nilsson, Emma |
author_facet |
Hawrylak, Monika Nilsson, Emma |
author_sort |
Hawrylak, Monika |
title |
Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
title_short |
Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
title_full |
Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
title_fullStr |
Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
title_full_unstemmed |
Spatial and Temporal Variations in a Perennial Firn Aquifer on Lomonosovfonna, Svalbard |
title_sort |
spatial and temporal variations in a perennial firn aquifer on lomonosovfonna, svalbard |
publisher |
Uppsala universitet, Institutionen för geovetenskaper |
publishDate |
2019 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384176 |
long_lat |
ENVELOPE(17.663,17.663,78.774,78.774) |
geographic |
Greenland Lomonosovfonna Svalbard |
geographic_facet |
Greenland Lomonosovfonna Svalbard |
genre |
Greenland Svalbard |
genre_facet |
Greenland Svalbard |
op_relation |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-384176 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766020266141417472 |