ABSTRACTIn the Scandinavian mountains several land-surfaces of different ages can be discerned. The youngest one is the Quaternary, glacially eroded surface still under formation. Sediment transport data, recorded downstream from the glacier Storglaciären, Swedish Lapland, and deep-sea records of benthicδ18O were used to calculate the time required for the formation of the glacial trough of this glacier and to discuss the climatic conditions under which subglacial erosion could have taken place. It was found that 300 000 years of glacial erosion were sufficient, but the process has been going on intermittently during 2.5 million years as relatively brief events, separated by extended periods of cold-based, non-erosive conditions. The erosional events were characterized by a climate ranging between the present one and a somewhat cooler, but still interglacial climate, similar to what was prevailing during isotopic substage 7c (about 235 000 years BP).