On the incidence of debris flows from the early Little Ice Age to a future greenhouse climate: A case study from the Swiss Alps

Abstract

Tree-ring based reconstructions of 123 debris-flow events in a case-study area of the Swiss Alps since AD 1570 show enhanced activity during the wet periods (1864-1895) following the last LIA glacier advance and in the early decades of the 20th century. In contrast, comparably low activity can be observed since 1995, with only one event recorded. From the reconstructions and based on RCM simulations, there are indications that debris-flow frequencies might continue to decrease in a future climate, as precipitation events are projected to occur less frequently in summer but become more common in soring or fall. Copyright 2006 by the American Geophysical Union.