Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation
©2017. American Geophysical Union. All Rights Reserved. Microtopographic variation that develops among features (troughs, rims, and centers) within polygonal landforms of coastal arctic tundra strongly affects movement of surface water and snow and thereby affects soil water contents (θ) and active...
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Language: | English |
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ftcdlib:qt09x4k422 2023-05-15T13:02:43+02:00 Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation Grant, RF Mekonnen, ZA Riley, WJ Wainwright, HM Graham, D Torn, MS 3161 - 3173 2017-12-01 application/pdf http://www.escholarship.org/uc/item/09x4k422 english eng eScholarship, University of California qt09x4k422 http://www.escholarship.org/uc/item/09x4k422 public Grant, RF; Mekonnen, ZA; Riley, WJ; Wainwright, HM; Graham, D; & Torn, MS. (2017). Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation. Journal of Geophysical Research: Biogeosciences, 122(12), 3161 - 3173. doi:10.1002/2017JG004035. Lawrence Berkeley National Laboratory: Retrieved from: http://www.escholarship.org/uc/item/09x4k422 article 2017 ftcdlib https://doi.org/10.1002/2017JG004035 2018-07-13T22:58:23Z ©2017. American Geophysical Union. All Rights Reserved. Microtopographic variation that develops among features (troughs, rims, and centers) within polygonal landforms of coastal arctic tundra strongly affects movement of surface water and snow and thereby affects soil water contents (θ) and active layer depth (ALD). Spatial variation in ALD among these features may exceed interannual variation in ALD caused by changes in climate and so needs to be represented in projections of changes in arctic ALD. In this study, increases in near-surface θ with decreasing surface elevation among polygon features at the Barrow Experimental Observatory (BEO) were modeled from topographic effects on redistribution of surface water and snow and from lateral water exchange with a subsurface water table during a model run from 1981 to 2015. These increases in θ caused increases in thermal conductivity that in turn caused increases in soil heat fluxes and hence in ALD of up to 15 cm with lower versus higher surface elevation which were consistent with increases measured at BEO. The modeled effects of θ caused interannual variation in maximum ALD that compared well with measurements from 1985 to 2015 at the Barrow Circumpolar Active Layer Monitoring (CALM) site (R2 = 0.61, RMSE = 0.03 m). For higher polygon features, interannual variation in ALD was more closely associated with annual precipitation than mean annual temperature, indicating that soil wetting from increases in precipitation may hasten permafrost degradation beyond that caused by soil warming from increases in air temperature. This degradation may be more rapid if increases in precipitation cause sustained wetting in higher features. Article in Journal/Newspaper Active layer monitoring Arctic Arctic permafrost Tundra University of California: eScholarship Arctic Journal of Geophysical Research: Biogeosciences 122 12 3161 3173 |
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Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
description |
©2017. American Geophysical Union. All Rights Reserved. Microtopographic variation that develops among features (troughs, rims, and centers) within polygonal landforms of coastal arctic tundra strongly affects movement of surface water and snow and thereby affects soil water contents (θ) and active layer depth (ALD). Spatial variation in ALD among these features may exceed interannual variation in ALD caused by changes in climate and so needs to be represented in projections of changes in arctic ALD. In this study, increases in near-surface θ with decreasing surface elevation among polygon features at the Barrow Experimental Observatory (BEO) were modeled from topographic effects on redistribution of surface water and snow and from lateral water exchange with a subsurface water table during a model run from 1981 to 2015. These increases in θ caused increases in thermal conductivity that in turn caused increases in soil heat fluxes and hence in ALD of up to 15 cm with lower versus higher surface elevation which were consistent with increases measured at BEO. The modeled effects of θ caused interannual variation in maximum ALD that compared well with measurements from 1985 to 2015 at the Barrow Circumpolar Active Layer Monitoring (CALM) site (R2 = 0.61, RMSE = 0.03 m). For higher polygon features, interannual variation in ALD was more closely associated with annual precipitation than mean annual temperature, indicating that soil wetting from increases in precipitation may hasten permafrost degradation beyond that caused by soil warming from increases in air temperature. This degradation may be more rapid if increases in precipitation cause sustained wetting in higher features. |
format |
Article in Journal/Newspaper |
author |
Grant, RF Mekonnen, ZA Riley, WJ Wainwright, HM Graham, D Torn, MS |
spellingShingle |
Grant, RF Mekonnen, ZA Riley, WJ Wainwright, HM Graham, D Torn, MS Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
author_facet |
Grant, RF Mekonnen, ZA Riley, WJ Wainwright, HM Graham, D Torn, MS |
author_sort |
Grant, RF |
title |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
title_short |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
title_full |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
title_fullStr |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
title_full_unstemmed |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation |
title_sort |
mathematical modelling of arctic polygonal tundra with ecosys: 1. microtopography determines how active layer depths respond to changes in temperature and precipitation |
publisher |
eScholarship, University of California |
publishDate |
2017 |
url |
http://www.escholarship.org/uc/item/09x4k422 |
op_coverage |
3161 - 3173 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Active layer monitoring Arctic Arctic permafrost Tundra |
genre_facet |
Active layer monitoring Arctic Arctic permafrost Tundra |
op_source |
Grant, RF; Mekonnen, ZA; Riley, WJ; Wainwright, HM; Graham, D; & Torn, MS. (2017). Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 1. Microtopography Determines How Active Layer Depths Respond to Changes in Temperature and Precipitation. Journal of Geophysical Research: Biogeosciences, 122(12), 3161 - 3173. doi:10.1002/2017JG004035. Lawrence Berkeley National Laboratory: Retrieved from: http://www.escholarship.org/uc/item/09x4k422 |
op_relation |
qt09x4k422 http://www.escholarship.org/uc/item/09x4k422 |
op_rights |
public |
op_doi |
https://doi.org/10.1002/2017JG004035 |
container_title |
Journal of Geophysical Research: Biogeosciences |
container_volume |
122 |
container_issue |
12 |
container_start_page |
3161 |
op_container_end_page |
3173 |
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1766319732422606848 |