Glacier Studies of the McCall Glacier, Alaska

Аннотация

Describes in detail this glacier in the Romanzof Mts., Brooks Range, northern Alaska, studied during the McCall Glacier Project, 1957-58. The crescent-shaped body of ice, approx. 8 km long, 640 m wide and 1,450 m high, has three cirques and a well defined drainage basin. From the confluence of the cirques, the ice drops in eight broad steps to the terminus. The hummocky ice surface is mantled with dust, rock and boulders which melt into the ice, causing cavities. Surface runoff from the cirques appears to flow into two main outlets: a marginal stream down the right side of the glacier, and circular fissure, located at the head of the glacier trunk. There are two principal areas of crevassing other than the ice faces above the cirques and the bergschrunds. The largest crevasse explored was 5 m wide, 60 m long and (estimated) 25 m deep. Blue bands and dirt-filled shear planes are common. Data collected include continuous records of long- and short-wave energy gain and loss, air temperatures, and wind speed. Investigations are noted of stratigraphy of snow, firn behavior, temperature gradients down to 100 m, and ice motion.