Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations
ABSTRACT A database of difficult-to-forecast natural persistent deep slab avalanches was analyzed to determine thresholds for parameters that contribute to their release in western Canada. The database included avalanche observations and weather station data. The avalanches were grouped based on the...
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Cambridge University Press (CUP)
2016
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Online Access: | http://dx.doi.org/10.1017/jog.2016.1 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000010 |
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crcambridgeupr:10.1017/jog.2016.1 2024-03-03T08:46:09+00:00 Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations CONLAN, MICHAEL JAMIESON, BRUCE 2016 http://dx.doi.org/10.1017/jog.2016.1 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000010 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 62, issue 232, page 243-255 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 2016 crcambridgeupr https://doi.org/10.1017/jog.2016.1 2024-02-08T08:27:19Z ABSTRACT A database of difficult-to-forecast natural persistent deep slab avalanches was analyzed to determine thresholds for parameters that contribute to their release in western Canada. The database included avalanche observations and weather station data. The avalanches were grouped based on their primary cause-of-release, either precipitation loading, wind loading, solar warming or air temperature warming using a multivariate classification tree, which first split using a solar warming parameter. The precipitation group had a median 24 h snowfall of 15 cm and 3 d snowfall of 38 cm at weather stations, mostly at or below treeline. These amounts were likely closer between 20–30 and 50–80 cm at alpine start zones. The wind loading group experienced the most wind-transported snow potential. The solar warming group had predicted solar warming of 5.2°C, 10 cm into the snowpack, on the days of release. The air temperature warming group experienced the highest median maximum air temperature (5°C) on the days of release. These thresholds may be useful to forecast the likelihood of similar avalanches with experienced-based forecasting or with decision aids, although many false alarms are possible. A companion paper, Part II, relates weather model data to avalanche occurrences. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Canada Journal of Glaciology 62 232 243 255 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes CONLAN, MICHAEL JAMIESON, BRUCE Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
topic_facet |
Earth-Surface Processes |
description |
ABSTRACT A database of difficult-to-forecast natural persistent deep slab avalanches was analyzed to determine thresholds for parameters that contribute to their release in western Canada. The database included avalanche observations and weather station data. The avalanches were grouped based on their primary cause-of-release, either precipitation loading, wind loading, solar warming or air temperature warming using a multivariate classification tree, which first split using a solar warming parameter. The precipitation group had a median 24 h snowfall of 15 cm and 3 d snowfall of 38 cm at weather stations, mostly at or below treeline. These amounts were likely closer between 20–30 and 50–80 cm at alpine start zones. The wind loading group experienced the most wind-transported snow potential. The solar warming group had predicted solar warming of 5.2°C, 10 cm into the snowpack, on the days of release. The air temperature warming group experienced the highest median maximum air temperature (5°C) on the days of release. These thresholds may be useful to forecast the likelihood of similar avalanches with experienced-based forecasting or with decision aids, although many false alarms are possible. A companion paper, Part II, relates weather model data to avalanche occurrences. |
format |
Article in Journal/Newspaper |
author |
CONLAN, MICHAEL JAMIESON, BRUCE |
author_facet |
CONLAN, MICHAEL JAMIESON, BRUCE |
author_sort |
CONLAN, MICHAEL |
title |
Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
title_short |
Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
title_full |
Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
title_fullStr |
Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
title_full_unstemmed |
Naturally triggered persistent deep slab avalanches in western Canada Part I: avalanche characteristics and weather trends from weather stations |
title_sort |
naturally triggered persistent deep slab avalanches in western canada part i: avalanche characteristics and weather trends from weather stations |
publisher |
Cambridge University Press (CUP) |
publishDate |
2016 |
url |
http://dx.doi.org/10.1017/jog.2016.1 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000010 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 62, issue 232, page 243-255 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2016.1 |
container_title |
Journal of Glaciology |
container_volume |
62 |
container_issue |
232 |
container_start_page |
243 |
op_container_end_page |
255 |
_version_ |
1792502125306052608 |