Air warming trends linked to permafrost warming in the sub-Arctic catchment of Tarfala, Sweden

Recent ground temperature records from the 100-m-deep borehole near the Tarfala Research Station in northern Sweden reveal that permafrost is warming at a pace consistent with the rate of measured air temperature increase at the site. Here we investigate whether air temperature increase is the main...

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Bibliographic Details
Published in:Polar Research
Main Authors: Romain Pannetier, Andrew Frampton
Format: Article in Journal/Newspaper
Language:English
Published: Norwegian Polar Institute 2016
Subjects:
geo
Online Access:https://doi.org/10.3402/polar.v35.28978
https://doaj.org/article/e0df8ab920034dfeb2b570677862cfc4
Description
Summary:Recent ground temperature records from the 100-m-deep borehole near the Tarfala Research Station in northern Sweden reveal that permafrost is warming at a pace consistent with the rate of measured air temperature increase at the site. Here we investigate whether air temperature increase is the main driver of the observed change in the permafrost thermal regime using a non-isothermal hydrogeological numerical model for partially frozen ground. The local site is investigated with different ground surface temperature scenarios representing different integrated effects of surficial heat attenuation processes. Results indicate that despite a short-term sensitivity to heat attenuation processes including snow conditions, the main driver of change in the permafrost thermal regime during the past decade is warming air temperatures. Additionally, the approach used here is shown to be particularly pertinent for modelling warming trends, despite limited prior knowledge of site-specific conditions and geological properties. Understanding the main driving mechanisms of changing permafrost is useful for assessing the suitability of borehole temperature records as proxies for past environmental conditions as well as for modelling possible future climatic impacts.