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Thawing permafrost and thicker active layers in sub‐arctic Sweden
Author(s) -
Åkerman H. Jonas,
Johansson Margareta
Publication year - 2008
Publication title -
permafrost and periglacial processes
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.867
H-Index - 76
eISSN - 1099-1530
pISSN - 1045-6740
DOI - 10.1002/ppp.626
Subject(s) - permafrost , active layer , snow , geology , arctic , physical geography , air temperature , the arctic , atmospheric sciences , climatology , geomorphology , layer (electronics) , oceanography , geography , materials science , composite material , thin film transistor
Observations of active‐layer thickness from nine sites with up to 29 years of gridded measurements located in the Torneträsk region, northernmost Sweden, were examined in relation to climatic trends. Mean annual air temperatures in this area have warmed and recently rose above 0°C. Active layers at all sites have become thicker, at rates ranging from 0.7 to 1.3 cm per year. This trend has accelerated in the past decade, especially in the westernmost site where rates have reached 2 cm per year and permafrost has disappeared at 81 per cent of the sampling points. Increased active‐layer thicknesses are correlated with increases in mean summer air temperature, thawing degree‐days and, in five of the nine sites, with increases in snow depth. Copyright © 2008 John Wiley & Sons, Ltd.