In situ nuclear magnetic resonance response of permafrost and active layer soil in boreal and tundra ecosystems

Mason A. Kass; Trevor P Irons; Burke J. Minsley; Neal J. Pastick; Dana R N Brown; Bruce K. Wylie

doi:10.5194/tc-2016-256

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In situ nuclear magnetic resonance response of permafrost and active layer soil in boreal and tundra ecosystems

Mason A. Kass·Trevor P Irons·Burke J. Minsley·Neal J. Pastick·Dana R N Brown·Bruce K. Wylie

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Abstract

Characterization of permafrost, particularly warm and near-surface permafrost which can contain significant liquid water, is critical to understanding complex interrelationships with climate change, ecosystems, and disturbances such as wildfires. Understanding the vulnerability and resilience of permafrost requires an interdisciplinary approach, relying on (for example) geophysical investigations, ecological characterization, direct observations, remote sensing, and more. As part of a multi-year investigation into the impacts of wildfires to permafrost, we have collected in situ measurements of the nuclear magnetic resonance (NMR) response of active layer and permafrost in a variety of soil conditions, types, and saturations. In this paper, we summarize the NMR data and present quantitative relationships between active layer and permafrost liquid water content and pore sizes. Through statistical analyses and synthetic freezing simulations, we also demonstrate that borehole NMR can image the nucleation of ice within soil pore spaces.

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Source-reported bounding extent: 50.98609893339354° to 71.45515260247822° latitude; -178.9453125° to -129.97169494628906° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Mason A. Kass, Trevor P Irons, Burke J. Minsley, Neal J. Pastick, Dana R N Brown, Bruce K. Wylie. 2017. In situ nuclear magnetic resonance response of permafrost and active layer soil in boreal and tundra ecosystems. https://doi.org/10.5194/tc-2016-256

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