Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation
Differences of surface elevation in arctic polygonal landforms cause spatial variation in soil water contents (θ), active layer depths (ALD), and thereby in CO2 and CH4 exchange. Here we test hypotheses in ecosys for topographic controls on CO2 and CH4 exchange in trough, rim, and center features of...
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ftcdlib:oai:escholarship.org:ark:/13030/qt2ws1v4tj 2024-02-11T10:01:04+01:00 Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation Grant, RF Mekonnen, ZA Riley, WJ Arora, B Torn, MS 3174 - 3187 2017-12-01 application/pdf https://escholarship.org/uc/item/2ws1v4tj unknown eScholarship, University of California qt2ws1v4tj https://escholarship.org/uc/item/2ws1v4tj public Journal of Geophysical Research Biogeosciences, vol 122, iss 12 Earth Sciences Atmospheric Sciences Climate Action Geophysics article 2017 ftcdlib 2024-01-15T19:05:26Z Differences of surface elevation in arctic polygonal landforms cause spatial variation in soil water contents (θ), active layer depths (ALD), and thereby in CO2 and CH4 exchange. Here we test hypotheses in ecosys for topographic controls on CO2 and CH4 exchange in trough, rim, and center features of low- and flat-centered polygons (LCP and FCP) against chamber and eddy covariance (EC) measurements during 2013 at Barrow, Alaska. Larger CO2 influxes and CH4 effluxes were measured with chambers and modeled with ecosys in LCPs than in FCPs and in lower features (troughs) than in higher (rims) within LCPs and FCPs. Spatially aggregated CO2 and CH4 fluxes from ecosys were significantly correlated with EC flux measurements. Lower features were modeled as C sinks (52–56gCm−2yr−1) and CH4 sources (4–6gCm−2yr−1), and higher features as near C neutral (−2–15gCm−2yr−1) and CH4 neutral (0.0–0.1gCm−2yr−1). Much of the spatial and temporal variations in CO2 and CH4 fluxes were modeled from topographic effects on water and snow movement and thereby on θ, ALD, and soil O2 concentrations. Model results forced with meteorological data from 1981 to 2015 indicated increasing net primary productivity in higher features and CH4 emissions in some lower and higher features since 2008, attributed mostly to recent rises in precipitation. Small-scale variation in surface elevation causes large spatial variation of greenhouse gas (GHG) exchanges and therefore should be considered in estimates of GHG exchange in polygonal landscapes. Article in Journal/Newspaper Arctic Barrow Tundra Alaska University of California: eScholarship Arctic |
institution |
Open Polar |
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University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
Earth Sciences Atmospheric Sciences Climate Action Geophysics |
spellingShingle |
Earth Sciences Atmospheric Sciences Climate Action Geophysics Grant, RF Mekonnen, ZA Riley, WJ Arora, B Torn, MS Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
topic_facet |
Earth Sciences Atmospheric Sciences Climate Action Geophysics |
description |
Differences of surface elevation in arctic polygonal landforms cause spatial variation in soil water contents (θ), active layer depths (ALD), and thereby in CO2 and CH4 exchange. Here we test hypotheses in ecosys for topographic controls on CO2 and CH4 exchange in trough, rim, and center features of low- and flat-centered polygons (LCP and FCP) against chamber and eddy covariance (EC) measurements during 2013 at Barrow, Alaska. Larger CO2 influxes and CH4 effluxes were measured with chambers and modeled with ecosys in LCPs than in FCPs and in lower features (troughs) than in higher (rims) within LCPs and FCPs. Spatially aggregated CO2 and CH4 fluxes from ecosys were significantly correlated with EC flux measurements. Lower features were modeled as C sinks (52–56gCm−2yr−1) and CH4 sources (4–6gCm−2yr−1), and higher features as near C neutral (−2–15gCm−2yr−1) and CH4 neutral (0.0–0.1gCm−2yr−1). Much of the spatial and temporal variations in CO2 and CH4 fluxes were modeled from topographic effects on water and snow movement and thereby on θ, ALD, and soil O2 concentrations. Model results forced with meteorological data from 1981 to 2015 indicated increasing net primary productivity in higher features and CH4 emissions in some lower and higher features since 2008, attributed mostly to recent rises in precipitation. Small-scale variation in surface elevation causes large spatial variation of greenhouse gas (GHG) exchanges and therefore should be considered in estimates of GHG exchange in polygonal landscapes. |
format |
Article in Journal/Newspaper |
author |
Grant, RF Mekonnen, ZA Riley, WJ Arora, B Torn, MS |
author_facet |
Grant, RF Mekonnen, ZA Riley, WJ Arora, B Torn, MS |
author_sort |
Grant, RF |
title |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
title_short |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
title_full |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
title_fullStr |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
title_full_unstemmed |
Mathematical Modelling of Arctic Polygonal Tundra with Ecosys: 2. Microtopography Determines How CO2 and CH4 Exchange Responds to Changes in Temperature and Precipitation |
title_sort |
mathematical modelling of arctic polygonal tundra with ecosys: 2. microtopography determines how co2 and ch4 exchange responds to changes in temperature and precipitation |
publisher |
eScholarship, University of California |
publishDate |
2017 |
url |
https://escholarship.org/uc/item/2ws1v4tj |
op_coverage |
3174 - 3187 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Barrow Tundra Alaska |
genre_facet |
Arctic Barrow Tundra Alaska |
op_source |
Journal of Geophysical Research Biogeosciences, vol 122, iss 12 |
op_relation |
qt2ws1v4tj https://escholarship.org/uc/item/2ws1v4tj |
op_rights |
public |
_version_ |
1790596808997601280 |