The Younger Dryas glaciation in the southeastern Monadhliath Mountains,Scotland: glacier reconstruction and palaeoclimate implications

Geomorphological mapping of locally nourished glaciers was conducted in four glens in the southeastern Monadhliath Mountains, Scotland. Three glaciers are interpreted to be of Younger Dryas age based on geomorphological similarity to features in other Scottish upland areas known to have been glaciated during the Younger Dryas, and on comparison to adjacent ice‐free areas in the lower glens where landform‐sediment assemblages typically reflect peri/paraglacial readjustment during the stadial. Here we reconstruct Younger Dryas glacier termini based on moraine alignments and associated geomorphological and sedimentological evidence. An adjacent wide plateau area at high altitude may have permitted extensive ice accumulation, but no unequivocal geomorphological signature is evident. To establish upper glacier limits, a series of ice profiles are modelled. The results yield a range of realistic glacier configurations bracketed between two distinct scenarios: a valley glaciation with the glaciers' upper limit on the plateau edge, and a low‐domed icecap centred on the plateau with ice flowing radially into the lower glens. Reconstructed equilibrium‐line altitudes are 795 m a.s.l. for the valley‐glacier scenario and 894 m a.s.l. for the icecap scenario. Calculated mean ablation‐season temperatures at the ELA are 1.2°C and 0.4°C for the valley‐glacier and the icecap scenario, respectively, from which we infer mean annual precipitation rates between 323 and 520 mm a^?1. Palaeoclimate results indicate a stadial climate in central Scotland 65–79% more arid than at present, comparable to that of western Norway for the stadial and to the present‐day Canadian Arctic.