Pleistocene/Holocene climate change, re-establishment of fluvial drainage network and increase in relief in the Swiss Alps

Data are presented about modern sediment discharge of the Swiss rivers and related to the size of catchments. The information reveals that the Central Alps have experienced denudation rates of approximate to0.15 mm yr(-1) in the foreland, and approximate to0.5 mm yr(-1) in the Alpine core. Mapping, however, indicates that modern erosion only affects 30-50% of the Alpine surface, and that fluvial and associated hillslope processes have focused erosion in 50-200-m-deep valleys. These valleys are incised into the glacial surface. If this limited spatial extent of erosion is considered, then effective erosion rates are significantly higher than average denudation rates. These effective rates equal or locally exceed modern rates of rock uplift. This implies that the modification of erosional processes related to the Pleistocene/Holocene climate change has resulted in an increase in the relief at a local scale. At a drainage basin scale, however, the relief appears not to change at present.