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Sylvi Haldorsen, Norwegian University of Life Sciences (Norway)
Michael Heim, Norwegian University of Life Sciences (Norway)
Barrie Dale, Univ. of Oslo (Norway)
Jon Y. Landvik, Norwegian University of Life Sciences (Norway)
Martine van der Ploeg, University of Wageningen (Netherlands)
Antoon Leijnse, University of Wageningen (Netherlands)
Otto Salvigsen, Univ. of Oslo (Norway)
Jon Ove Hagen, Univ. of Oslo (Norway)
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Deep subpermafrost aquifers in polar areas are highly dependent on climate. The permafrost forms an aquitard that prevents groundwater recharge and discharge. A study from the high-arctic island of Spitsbergen, Svalbard shows that during a glacial to interglacial phase, both the permafrost and the glacier regime will respond to climatic changes, and a glacier-fed groundwater flow system will vary accordingly. A full glaciation results in the melting of permafrost and groundwater can flow through pores and fracture systems in the rocks and sediments below the temperate zones of glaciers. These groundwater flow systems will mainly be localised to fjords and valleys and form low-lying terrestrial springs when the sea level drops during deglaciation. During an interglacial, new permafrost is formed and the groundwater recharge and discharge areas will thereby be gradually reduced to a minimum reached at the warmest part of an interglacial. An already frozen spring system cannot re-open before the permafrost melts. Only groundwater springs related to permanently warm-based glacial ice will persist into the next glaciation. During a new glaciation flow systems that terminated during the previous interglacial may become re-vitalised if overridden by warm-based ice. We believe this climate-driven cycle to be relevant also for other high-arctic groundwater systems.
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