Inventory methodology of periglacial lakes in Spitzbergen (Svalbard)

Abstract

The paper discusses periglacial lakes, which were formed after the Little Ice Age due to the reduction of Spitzbergen (Svalbard) glaciation. A method for inventorying the periglacial lakes in Spitzbergen (Svalbard) is proposed based on the Norwegian Polar Institute cartographic materials and remote sensing methods. Such lakes have been formed due to deglaciation in Svalbard since the beginning of the 20th century after the Little Ice Age. Three morphological features of the periglacial lake were used as selection criteria: the lake is in contact with the glacier, the lake is located within the terminal moraine or borders on it, each of which is sufficient.As a result of the inventory, 705 periglacial lakes have been found in Spitzbergen (Svalbard). The largest number of lakes is located in the northeastern part of the archipelago, where the relief is poorly dissected. The largest clusters of lakes are found on the moraines of mountain-valley glaciers located on the warmer western coasts. The periglacial lakes were divided into 5 types: glacier-dammed lakes (19 %), lakes in contact with the glacier front (30 %), thermokarst lakes on the moraine (27 %), moraine-dammed lakes (15 %) and lakes in contact with the terminal moraine (9 %). The most numerous were periglacial lakes adjoining the glacier (about 50 %). Their total area is 162 km2 and accounts for 87 % of the total area of all periglacial lakes. The other half of the lakes have formed shores, and their transformation is likely to be much slower in the future. The quantitative ratio of lake types testifies to the active phase of the process of lake expansion in the archipelago. This ratio of lakes by groups can be a clear indicator of climate change in the archipelago.