Atmospheric circulation patterns associated with avalanche cycles in the Troms region
Snow avalanches endangers human lives and infrastructure situated in alpine environments during the winter season. Occurrence of avalanche activity is a product of processes taking place in the snow cover situated in steep terrain, which are governed by meteorological conditions induced by synoptic...
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UiT Norges arktiske universitet
2018
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Online Access: | https://hdl.handle.net/10037/12876 |
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ftunivtroemsoe:oai:munin.uit.no:10037/12876 2023-05-15T17:36:10+02:00 Atmospheric circulation patterns associated with avalanche cycles in the Troms region Jenssen, Marius 2018-05-15 https://hdl.handle.net/10037/12876 eng eng UiT Norges arktiske universitet UiT The Arctic University of Norway https://hdl.handle.net/10037/12876 openAccess Copyright 2018 The Author(s) VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 GEO-3900 Master thesis Mastergradsoppgave 2018 ftunivtroemsoe 2021-06-25T17:55:58Z Snow avalanches endangers human lives and infrastructure situated in alpine environments during the winter season. Occurrence of avalanche activity is a product of processes taking place in the snow cover situated in steep terrain, which are governed by meteorological conditions induced by synoptic weather patterns. Avalanche forecasting can therefore better forecast avalanche activity if they understand the causal relationship between atmospheric circulation patterns and the boundary layer conditions responsible for the triggering of avalanches. Such an analysis has never previously been done for the studied region. This study assesses the occurrence of periods with high avalanche activity in Troms, Northern Norway with respect to the governing atmospheric circulation patterns and the meteorological conditions they induce. An avalanche activity dataset for the 16/17 winter season was used to distinguish nine avalanche cycles and meteorological observations for these cycles from local weather stations were used to describe the conditions leading to avalanche activity. Then, 500mb geopotential height maps, 850mb geopotential height maps and mean sea level pressure plots over the North Atlantic region were downloaded from NCEP/NCAR reanalysis project for avalanche cycle periods, and were used to categorize five synoptic situations responsible for these avalanche cycles. Avalanche cycle days are characterized by higher wind speeds and lower temperatures relative to the rest of the winter, causing wind transport of snow and delayed stabilization of the snowpack. The different synoptic types induces a range of meteorological settings causing avalanches, and the most prominent for avalanching are the induction of snow precipitation and wind, causing storm and wind slab avalanches during winter, and conditions favorable for warming events and subsequent wet snow avalanche activity in the end of the snow season. Master Thesis North Atlantic Northern Norway Troms University of Tromsø: Munin Open Research Archive Norway |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 GEO-3900 |
spellingShingle |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 GEO-3900 Jenssen, Marius Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
topic_facet |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 GEO-3900 |
description |
Snow avalanches endangers human lives and infrastructure situated in alpine environments during the winter season. Occurrence of avalanche activity is a product of processes taking place in the snow cover situated in steep terrain, which are governed by meteorological conditions induced by synoptic weather patterns. Avalanche forecasting can therefore better forecast avalanche activity if they understand the causal relationship between atmospheric circulation patterns and the boundary layer conditions responsible for the triggering of avalanches. Such an analysis has never previously been done for the studied region. This study assesses the occurrence of periods with high avalanche activity in Troms, Northern Norway with respect to the governing atmospheric circulation patterns and the meteorological conditions they induce. An avalanche activity dataset for the 16/17 winter season was used to distinguish nine avalanche cycles and meteorological observations for these cycles from local weather stations were used to describe the conditions leading to avalanche activity. Then, 500mb geopotential height maps, 850mb geopotential height maps and mean sea level pressure plots over the North Atlantic region were downloaded from NCEP/NCAR reanalysis project for avalanche cycle periods, and were used to categorize five synoptic situations responsible for these avalanche cycles. Avalanche cycle days are characterized by higher wind speeds and lower temperatures relative to the rest of the winter, causing wind transport of snow and delayed stabilization of the snowpack. The different synoptic types induces a range of meteorological settings causing avalanches, and the most prominent for avalanching are the induction of snow precipitation and wind, causing storm and wind slab avalanches during winter, and conditions favorable for warming events and subsequent wet snow avalanche activity in the end of the snow season. |
format |
Master Thesis |
author |
Jenssen, Marius |
author_facet |
Jenssen, Marius |
author_sort |
Jenssen, Marius |
title |
Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
title_short |
Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
title_full |
Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
title_fullStr |
Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
title_full_unstemmed |
Atmospheric circulation patterns associated with avalanche cycles in the Troms region |
title_sort |
atmospheric circulation patterns associated with avalanche cycles in the troms region |
publisher |
UiT Norges arktiske universitet |
publishDate |
2018 |
url |
https://hdl.handle.net/10037/12876 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
North Atlantic Northern Norway Troms |
genre_facet |
North Atlantic Northern Norway Troms |
op_relation |
https://hdl.handle.net/10037/12876 |
op_rights |
openAccess Copyright 2018 The Author(s) |
_version_ |
1766135573760704512 |