The <scp>Y</scp>ounger <scp>D</scp>ryas climatic conditions in the <scp>Z</scp>a <scp>M</scp>nichem <scp>V</scp>alley (<scp>P</scp>olish <scp>H</scp>igh <scp>T</scp>atra <scp>M</scp>ountains) based on exposure‐age dating and glacier‐climate modelling

Abstract

Cosmogenic 36 Cl was measured in bedrock and moraine boulders in the Z a M nichem V alley ( H igh T atra M ountains). The post‐ LGM deglaciation of the study area occurred about 15.9 ka ago. The northernmost part of the valley slopes was ice‐free around 15 ka ago. The terminal moraine on the valley threshold was finally stabilized 12.5 ka ago during the Y ounger D ryas cold event ( G reenland S tadial 1). At that time, the Z a M nichem glacier was 1.3 km long and had an area of 0.57 km 2 . The AAR equilibrium line of the glacier was located at 1990 m a.s.l., which corresponds to an ELA depression of ∼500 m compared to today. The mean summer temperature was colder by 4°–4.5° C than the present‐day temperature. The mean annual temperature was colder by 6° C than today. Such conditions suggest a decrease of the annual precipitation by ∼15–25% compared with the present‐day annual average. These data indicate a probable uniform temperature change across central and western E urope, with the precipitation being the most significant factor affecting the mass balance of mountain glaciers. The spatial distribution of balance data suggests increasing continentality towards the east during the Y ounger D ryas.