Reply on RC1

TL;DR: In this article , the authors used a regional climate model to investigate the physical processes sustaining the glacier extent during the last glacial maximum (LGM) and found a predominance of convection during summer and increased southwesterly stratiform precipitation over the southern Alps compared to pre-industrial conditions.

Abstract: Evidence that during the Last Glacial Maximum (LGM) glaciers extended well into the piedmont planes is still identifiable in the alpine foreland as a system of well-preserved moraines. Glaciers are strongly affected by temperature and precipitation and therefore they are excellent indicators of climate change. Here we use a regional climate model (RCM) to investigate the physical processes sustaining the glacier extent during the LGM. We find a predominance of convection during summer and increased southwesterly stratiform precipitation over the southern Alps compared to pre-industrial conditions. This precipitation pattern, along with lower temperatures, determined summer snowfall extending to low elevations with a consequent substantial drop of the equilibrium line altitude (ELA) consistent with the estimated LGM glacier extent. Our RCM based estimates of the ELA at the LGM yield excellent consistency with Alpine glacier reconstructions, further demonstrating the great potential of this technique for use in paleoclimate studies.