| Summary: | Changes in water surface area (w.s.a.) in Arctic regions have been linked to climate warming and permafrost degradation (Briggs et al. 2014). As permafrost thaws, thermokarst lakes are formed. This causes the surface to get wetter. Although, a drying of the surface has often been observed in areas of discontinuous permafrost. As the climate warms, permafrost starts to thaw from underneath the lakes, causing drainage from below to be possible. The permafrost around lake Torneträsk, northern Sweden, has been degrading over the past few decades (Akerman and Johansson 2008), and a change in surface wetness has been observed (Christensen et al. 2004b). In this thesis, the change in w.s.a. of the Torneträsk region, as well as its relation to air temperature, precipitation, snow depth and active layer thickness has been investigated by analysing satellite images taken between 1990 to 2015. The w.s.a. in the Torneträsk region has been declining over the past 25 years. This decline however has only been observed in the permafrost free zones and the areas with sporadic permafrost. The areas underlain by continuous and discontinuous permafrost observed an increase in w.s.a. However, no significant relationships were found between the change in w.s.a. and climatic factors, since the study was too short. The Arctic region has experienced a rapidly changing climate and this has major influences on the characteristics of this region. Air temperatures have been rising in most areas of the Arctic region since the 1960’s, with an acceleration in rising air temperatures measured since the 1980’s (Serreze and Walsh 2000; Smith et al. 2005). The warming of the Arctic triggered changes in the cryosphere, including a warming and degradation of the permafrost, as well as a thickening of the active layer above the permafrost (Hinzman et al. 2005). This causes changes in the water surface area (w.s.a.) of Arctic regions, as this have been linked to climate warming and permafrost degradation (Briggs et al. 2014). Climate warming causes ...
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