Glacier Surges

Abstract

Surge-type glaciers periodically undergo large flow acceleration after extended quiescent phases of slow movement, usually accompanied by terminus advance. Such glaciers are relatively rare but occur in many of the world's glacierized areas. High water pressures and extreme basal sliding are obvious characteristics but key questions concerning this, usually spectacular phenomenon, remain open. Why are glaciers in some regions surge-type but not in others, what sort of "memory" lets glaciers surge again and again, what is the influence of climate, geology, and topography? Besides their scientific interest, glacier surges can also be a threat to humans, especially in connection with rapidly forming lakes and their sudden outbursts. Cases of hazard- and disaster-related glacier surges are described from the Pamirs, the Andes, the Italian Alps, and Alaska.