Coastal landscape degradation and disappearance of Davislaguna Lake, Sørkappland, Svalbard, 1900-2021

The paper describes the transformation of the coastal landscape near former Davislaguna Lake, SE Spitsbergen. It is a comparative study which outlines the changing state of the area based on old maps, other archival materials, remote sensing data from the years 1900 to 2021, and our own fieldwork performed since 2005. The indirect cause of this transformation is identified herein as climate warming which has produced a progressive degradation of the cryosphere and triggered three key forces behind the said transformation: glacial recession in the 20th century, shortening of the sea-ice season, permafrost thawing in the 21st century. From the year 1900 to the 1920s the coastal landscape of the study area consisted of a bay with beaches between a mountain range in the west and a tidewater glacier tongue protruding into the sea in the northeast. The tongue subsequently melted and the bay became transformed into a coastal plain, with the resulting lake becoming separated from the sea by a gravel-sand bar by 1936. Afterwards, both the plain and lake dwindled in size due to the decline of the bar found to the west. This process continued until the lake became divided into two parts in the 1980s; one of these then disappeared between 2006 and 2010, and the second one by 2021. Hence, the land in question, with the coastal plain partly glaciated and surrounding the bay, then unglaciated and surrounding the lake, became over time replaced by the sea. Today, the process of abrasion acting near the sea is destroying the remaining beaches and cutting down the steep slopes of area mountains and ice-cored moraines.