SEA ICE OVERFLOOD IN STEFANSSON SOUND, ALASKAN BEAUFORT SEA

摘要

This paper describes the methods used to delineate the seaward limits of sea ice overflood from three river systems discharging into the Alaskan Beaufort Sea to the east of Prudhoe Bay. An understanding of this annual natural event is required for planning new offshore developments in the Prudhoe Bay area. For example, estimates of the effects of strudel scour on offshore pipeline design are based on this data. This program reviewed previously published work, and integrated industry-sponsored helicopter surveys with a new series of overflood maps interpreted from historical Landsat imagery for the period 1973 to 1986. As a result, the overall historical record was more than doubled, from 5 to 11 years. Overflood originating predominantly from the Saganavirktok River was shown to extend to a distance up to 5 km from shore, reaching water depths in the 3 to 5 m range over much of the study area. Newer satellite platforms such as Landsat 7, Radarsat and IKONOS could be used in the future to resolve much finer surface details, including the possibility of mapping ice surface drainage patterns, indicative of areas having the potential for strudel scours in the seabed.