At the end of the last glacial period, the Vilnius hilly area, which is on the edge of the glacier, was still a plateau shackled by perennial frost. A sudden warming of the climate in the post-glacial period thawed the frost and started the sliding of soil masses towards the valleys of the Neris and Vilnia rivers. Thus, thermoerosion hollowed out the major ravines and valleys, forming the main features of the erosional hills of Vilnius. Thermoerosion is also occurring during the current climate warming in permafrost regions, i.e. in Canada and Siberia.
The Saulės Slėnis valley in Antakalnis, which is easy to visit and explore, could be a benchmark phenomenon of thermoerosion.
It might be worth declaring the Saulės Slėnis valley a natural heritage site. It does not currently appear to be at risk of urbanisation or destruction, but as a natural heritage site the valley would spread the knowledge of past climate change more widely.
The thermoerosive hilly area of Vilnius is unique not only in Lithuania, but also in Europe. Lithuanian geologists are therefore submitting it as a candidate for the World Geological Heritage List, which is being prepared by the International Union of Geological Sciences (IUGS) together with UNESCO. Interestingly, the Saulės Slėnis valley inspires creativity – it is depicted in Stasys Jusionis’ painting “Autumn in Sapieginė” (1993).
Laboratory of Climate and Water Research
