Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic
Permafrost and active layer thickness (ALT) vary considerably spatially and in response and sensitivity to warming. Understanding the driving influences behind local scale variability and sensitivity is important to guide regional studies. Heterogeneity in the thermal state of permafrost (TSP), ALT...
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Lethbridge, Alta. : University of Lethbridge, Dept. of Geography and Environment
2023
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ftunivlethb:oai:opus.uleth.ca:10133/6592 2023-10-29T02:29:39+01:00 Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic Garibaldi, Madeleine C. University of Lethbridge. Faculty of Arts and Science Bonnaventure, Philip 2023 application/pdf https://hdl.handle.net/10133/6592 en eng Lethbridge, Alta. : University of Lethbridge, Dept. of Geography and Environment Department of Geography and Environment Arts and Science Thesis (University of Lethbridge. Faculty of Arts and Science) https://hdl.handle.net/10133/6592 TTOP model permafrost elevation dependent warming active layer Canada Permafrost--Research--Canada Northern Permafrost--Mathematical models--Research--Canada Permafrost--Thermal properties--Research--Canada Climatic changes--Research--Canada Global warming--Research--Canada Earth temperature--Research--Canada Dissertations Academic Thesis 2023 ftunivlethb 2023-09-30T23:00:40Z Permafrost and active layer thickness (ALT) vary considerably spatially and in response and sensitivity to warming. Understanding the driving influences behind local scale variability and sensitivity is important to guide regional studies. Heterogeneity in the thermal state of permafrost (TSP), ALT and the most important influences on each were analyzed across the western Canadian Arctic and Subarctic. Spatial differences in ALT were related to ecoregional characteristics with increasing average ALT by ecoregion moving south (68 cm to 126 cm) and high variability in ALT for shrub dominated ecoregions (up to 145 cm). The sensitivity of the permafrost model varied between regions, highlighting the importance of winter conditions with less than 60 % of observations remaining within 1 ºC of the original value compared to 72 % for the thawing conditions. Local models of permafrost presence compared to regional models both under current (33% compared to 77%) and future climates (71% compared to 10%) demonstrated the unreliability of regional models in locations where the underlying model assumptions were not valid. Ultimately, the importance of using locally measured data to characterize and adjust regional assumptions was demonstrated. Finally, differential magnitudes of thermal responses to warming (up to 5 ºC), based on the connectivity of the air and ground thermal regime across the analysis, underscores the potential for permafrost resilience and the need to account for variable surface offsets when predicting future permafrost distribution maps. Thesis Active layer thickness Arctic Global warming permafrost Subarctic University of Lethbridge Institutional Repository |
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Open Polar |
collection |
University of Lethbridge Institutional Repository |
op_collection_id |
ftunivlethb |
language |
English |
topic |
TTOP model permafrost elevation dependent warming active layer Canada Permafrost--Research--Canada Northern Permafrost--Mathematical models--Research--Canada Permafrost--Thermal properties--Research--Canada Climatic changes--Research--Canada Global warming--Research--Canada Earth temperature--Research--Canada Dissertations Academic |
spellingShingle |
TTOP model permafrost elevation dependent warming active layer Canada Permafrost--Research--Canada Northern Permafrost--Mathematical models--Research--Canada Permafrost--Thermal properties--Research--Canada Climatic changes--Research--Canada Global warming--Research--Canada Earth temperature--Research--Canada Dissertations Academic Garibaldi, Madeleine C. University of Lethbridge. Faculty of Arts and Science Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
topic_facet |
TTOP model permafrost elevation dependent warming active layer Canada Permafrost--Research--Canada Northern Permafrost--Mathematical models--Research--Canada Permafrost--Thermal properties--Research--Canada Climatic changes--Research--Canada Global warming--Research--Canada Earth temperature--Research--Canada Dissertations Academic |
description |
Permafrost and active layer thickness (ALT) vary considerably spatially and in response and sensitivity to warming. Understanding the driving influences behind local scale variability and sensitivity is important to guide regional studies. Heterogeneity in the thermal state of permafrost (TSP), ALT and the most important influences on each were analyzed across the western Canadian Arctic and Subarctic. Spatial differences in ALT were related to ecoregional characteristics with increasing average ALT by ecoregion moving south (68 cm to 126 cm) and high variability in ALT for shrub dominated ecoregions (up to 145 cm). The sensitivity of the permafrost model varied between regions, highlighting the importance of winter conditions with less than 60 % of observations remaining within 1 ºC of the original value compared to 72 % for the thawing conditions. Local models of permafrost presence compared to regional models both under current (33% compared to 77%) and future climates (71% compared to 10%) demonstrated the unreliability of regional models in locations where the underlying model assumptions were not valid. Ultimately, the importance of using locally measured data to characterize and adjust regional assumptions was demonstrated. Finally, differential magnitudes of thermal responses to warming (up to 5 ºC), based on the connectivity of the air and ground thermal regime across the analysis, underscores the potential for permafrost resilience and the need to account for variable surface offsets when predicting future permafrost distribution maps. |
author2 |
Bonnaventure, Philip |
format |
Thesis |
author |
Garibaldi, Madeleine C. University of Lethbridge. Faculty of Arts and Science |
author_facet |
Garibaldi, Madeleine C. University of Lethbridge. Faculty of Arts and Science |
author_sort |
Garibaldi, Madeleine C. |
title |
Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
title_short |
Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
title_full |
Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
title_fullStr |
Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
title_full_unstemmed |
Understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the Western Canadian Arctic and Subarctic |
title_sort |
understanding the spatial and temporal heterogeneity of permafrost at a range of scales across the western canadian arctic and subarctic |
publisher |
Lethbridge, Alta. : University of Lethbridge, Dept. of Geography and Environment |
publishDate |
2023 |
url |
https://hdl.handle.net/10133/6592 |
genre |
Active layer thickness Arctic Global warming permafrost Subarctic |
genre_facet |
Active layer thickness Arctic Global warming permafrost Subarctic |
op_relation |
Thesis (University of Lethbridge. Faculty of Arts and Science) https://hdl.handle.net/10133/6592 |
_version_ |
1781055306848010240 |