surging glacier

A surging glacier is a type of glacier that, after a period of normal flow, suddenly begins to move very rapidly, up to five meters per hour. This rapid flow typically lasts only a year or two. During this surge, the upper part of the glacier depletes, while the lower part swells and advances, though usually not beyond previous surge limits.1

These surges occur periodically and are independent of climate changes. The cause is generally an abrupt decoupling of the glacier from its bed, often due to a breakdown in the subglacial water flow system. While surging glaciers are found in areas like the Alaska Range, they are absent in other regions with similar conditions. Glacier outburst floods, also known as jökulhlaups, can occur when water is stored within or behind a glacier and is suddenly released.12