Linking tundra vegetation, snow, soil temperature, and permafrost
Connections between vegetation and soil thermal dynamics are critical for estimating the vulnerability of permafrost to thaw with continued climate warming and vegetation changes. The interplay of complex biophysical processes results in a highly heterogeneous soil temperature distribution on small...
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ftcopernicus:oai:publications.copernicus.org:bg84432 2023-05-15T13:02:55+02:00 Linking tundra vegetation, snow, soil temperature, and permafrost Grünberg, Inge Wilcox, Evan J. Zwieback, Simon Marsh, Philip Boike, Julia 2020-08-26 application/pdf https://doi.org/10.5194/bg-17-4261-2020 https://bg.copernicus.org/articles/17/4261/2020/ eng eng doi:10.5194/bg-17-4261-2020 https://bg.copernicus.org/articles/17/4261/2020/ eISSN: 1726-4189 Text 2020 ftcopernicus https://doi.org/10.5194/bg-17-4261-2020 2020-08-31T16:22:12Z Connections between vegetation and soil thermal dynamics are critical for estimating the vulnerability of permafrost to thaw with continued climate warming and vegetation changes. The interplay of complex biophysical processes results in a highly heterogeneous soil temperature distribution on small spatial scales. Moreover, the link between topsoil temperature and active layer thickness remains poorly constrained. Sixty-eight temperature loggers were installed at 1–3 cm depth to record the distribution of topsoil temperatures at the Trail Valley Creek study site in the northwestern Canadian Arctic. The measurements were distributed across six different vegetation types characteristic for this landscape. Two years of topsoil temperature data were analysed statistically to identify temporal and spatial characteristics and their relationship to vegetation, snow cover, and active layer thickness. The mean annual topsoil temperature varied between − 3.7 and 0.1 ∘ C within 0.5 km 2 . The observed variation can, to a large degree, be explained by variation in snow cover. Differences in snow depth are strongly related with vegetation type and show complex associations with late-summer thaw depth. While cold winter soil temperature is associated with deep active layers in the following summer for lichen and dwarf shrub tundra, we observed the opposite beneath tall shrubs and tussocks. In contrast to winter observations, summer topsoil temperature is similar below all vegetation types with an average summer topsoil temperature difference of less than 1 ∘ C. Moreover, there is no significant relationship between summer soil temperature or cumulative positive degree days and active layer thickness. Altogether, our results demonstrate the high spatial variability of topsoil temperature and active layer thickness even within specific vegetation types. Given that vegetation type defines the direction of the relationship between topsoil temperature and active layer thickness in winter and summer, estimates of permafrost vulnerability based on remote sensing or model results will need to incorporate complex local feedback mechanisms of vegetation change and permafrost thaw. Text Active layer thickness Arctic permafrost Tundra Copernicus Publications: E-Journals Arctic Trail Valley Creek ENVELOPE(-133.415,-133.415,68.772,68.772) Valley Creek ENVELOPE(-138.324,-138.324,63.326,63.326) Biogeosciences 17 16 4261 4279 |
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Open Polar |
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Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Connections between vegetation and soil thermal dynamics are critical for estimating the vulnerability of permafrost to thaw with continued climate warming and vegetation changes. The interplay of complex biophysical processes results in a highly heterogeneous soil temperature distribution on small spatial scales. Moreover, the link between topsoil temperature and active layer thickness remains poorly constrained. Sixty-eight temperature loggers were installed at 1–3 cm depth to record the distribution of topsoil temperatures at the Trail Valley Creek study site in the northwestern Canadian Arctic. The measurements were distributed across six different vegetation types characteristic for this landscape. Two years of topsoil temperature data were analysed statistically to identify temporal and spatial characteristics and their relationship to vegetation, snow cover, and active layer thickness. The mean annual topsoil temperature varied between − 3.7 and 0.1 ∘ C within 0.5 km 2 . The observed variation can, to a large degree, be explained by variation in snow cover. Differences in snow depth are strongly related with vegetation type and show complex associations with late-summer thaw depth. While cold winter soil temperature is associated with deep active layers in the following summer for lichen and dwarf shrub tundra, we observed the opposite beneath tall shrubs and tussocks. In contrast to winter observations, summer topsoil temperature is similar below all vegetation types with an average summer topsoil temperature difference of less than 1 ∘ C. Moreover, there is no significant relationship between summer soil temperature or cumulative positive degree days and active layer thickness. Altogether, our results demonstrate the high spatial variability of topsoil temperature and active layer thickness even within specific vegetation types. Given that vegetation type defines the direction of the relationship between topsoil temperature and active layer thickness in winter and summer, estimates of permafrost vulnerability based on remote sensing or model results will need to incorporate complex local feedback mechanisms of vegetation change and permafrost thaw. |
format |
Text |
author |
Grünberg, Inge Wilcox, Evan J. Zwieback, Simon Marsh, Philip Boike, Julia |
spellingShingle |
Grünberg, Inge Wilcox, Evan J. Zwieback, Simon Marsh, Philip Boike, Julia Linking tundra vegetation, snow, soil temperature, and permafrost |
author_facet |
Grünberg, Inge Wilcox, Evan J. Zwieback, Simon Marsh, Philip Boike, Julia |
author_sort |
Grünberg, Inge |
title |
Linking tundra vegetation, snow, soil temperature, and permafrost |
title_short |
Linking tundra vegetation, snow, soil temperature, and permafrost |
title_full |
Linking tundra vegetation, snow, soil temperature, and permafrost |
title_fullStr |
Linking tundra vegetation, snow, soil temperature, and permafrost |
title_full_unstemmed |
Linking tundra vegetation, snow, soil temperature, and permafrost |
title_sort |
linking tundra vegetation, snow, soil temperature, and permafrost |
publishDate |
2020 |
url |
https://doi.org/10.5194/bg-17-4261-2020 https://bg.copernicus.org/articles/17/4261/2020/ |
long_lat |
ENVELOPE(-133.415,-133.415,68.772,68.772) ENVELOPE(-138.324,-138.324,63.326,63.326) |
geographic |
Arctic Trail Valley Creek Valley Creek |
geographic_facet |
Arctic Trail Valley Creek Valley Creek |
genre |
Active layer thickness Arctic permafrost Tundra |
genre_facet |
Active layer thickness Arctic permafrost Tundra |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-17-4261-2020 https://bg.copernicus.org/articles/17/4261/2020/ |
op_doi |
https://doi.org/10.5194/bg-17-4261-2020 |
container_title |
Biogeosciences |
container_volume |
17 |
container_issue |
16 |
container_start_page |
4261 |
op_container_end_page |
4279 |
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1766324100886691840 |