Popis: |
Ice caps once covered large areas of Montenegro in the Balkans. The largest ice cap covered an area of >1000 km2 and covered large areas of central Montenegro, including the Durmitor, Sinjajevina and Morača massifs. A smaller ice cap, yet still covering an area of 165 km2, covered Mount Orjen on the Adriatic coast. More than 30 U-series dates from secondary carbonates cementing moraines across Montenegro indicates that the most extensive glaciation occurred during the Middle Pleistocene, correlating with a major phase of glaciation in Greece to the south during MIS 12 (c. 480-430 ka). Later, less extensive, glaciations are also recorded in the cirques and valleys and correlate with glaciations during MIS 6 (190-130 ka) and MIS 5d-2 (110-11.7 ka). The formation of large ice caps over Montenegro on mountains reaching only 2500 m indicates sustained moisture supply during Pleistocene cold stages – especially on the lower mountains of the coast such as Mount Orjen. Such sustained precipitation supply during Pleistocene cold stages is likely to have been facilitated by major temperature contrasts between the European landmass and the Mediterranean Sea, which are likely to have sustained lee-side vortices to the south of the Alps, in the Gulf of Genoa and Adriatic Sea, forming weak moisture-bearing depressions which tracked across the eastern Adriatic coastal mountains. Large ice caps on the Dinaric Alps would have blocked the inland penetration of these depressions, resulting in much drier conditions in the Balkan interior, creating favourable conditions for the deposition of thick accumulations of loess. In the Durmitor massif, the highest in Montenegro, valley glaciers were present during the Younger Dryas (12.9-11.7 ka) and confirm the influence of North Atlantic Ocean circulation on Pleistocene climate change in this part of the Mediterranean. In this same massif only one small cirque glacier survives today and exists under conditions strongly controlled by local topoclimatic controls. |