Permafrost Distribution and Temperatures in Europe During the Younger Dryas

Permafrost distribution and temperatures in Europe during the Younger Dryas stadial are reconstructed based on an assessment of periglacial phenomena attributed to this cold interval. The significance of immature ice-wedge casts showing characteristics of both ice-wedge casts and frost cracks is discussed. Careful evaluation of periglacial features enables quantification of the mean annual air temperature and mean temperature of the coldest month. Results suggest that, during the coldest part of the Younger Dryas, continuous permafrost existed north of ∼54°N (i.e. in Fennoscandia and the northern part of the British Isles and Ireland). Mean annual air temperatures at sea level near or below −8°C and mean temperatures of the coldest month well below −20°C are deduced for this zone. Discontinuous permafrost was present between 54°N and 50°N (i.e. in central and southern England and Ireland, The Netherlands, upland Belgium, northern Germany and Poland). It is suggested that in this zone mean annual air temperatures were between −8°C and −1°C, with mean temperatures of the coldest month above −20°C.