Glacier Terminus Fluctuations in the Wrangell and Chugach Mountains Resulting from Non-Climate Controls

• Main Authors: Sturm, Matthew, Hall, Dorothy K., Benson, Carl S., Field, William O.
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB FORT WAINWRIGHT AK
• Format: Text
• Language: English
• Published: 1992
• Subjects: Geography; Snow; Ice and Permafrost; *GLACIERS; *VOLCANOES; ALASKA; CRATERS; FJORDS; FLOW; HEATING; ICE; IMAGES; MEASUREMENT; MOUNTAINS; PHOTOGRAMMETRY; RATES; REGIONS; SOUND; STATIONARY; SURVEYS; TIDEWATER; UNIVERSITIES; SYMPOSIA; CLIMATE; ARCTIC REGIONS; Component Reports; *Terminus; *Wrangell mountains; *Chugach mountains; *Non-climatic controls; Dynamic controls; Volcanic meltwater; Arctic; Fairbanks; ahtna; glacier; glaciers; Ice; permafrost; Tidewater; Alaska
• Online Access: http://www.dtic.mil/docs/citations/ADP007334; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADP007334

Non-climatically controlled fluctuations of glacier termini were studied in two regions in Alaska. In the Wrangell Mountains, eight glaciers on Mt. Wrangell, an active volcano, have been monitored over the past 30 years using terrestrial surveys, aerial photogrammetry and digitally registered satellite images. Results, which are consistent between different methods of measurement, indicate that the termini of most glaciers were stationary or had retreated slightly. However, the termini of the 30-km-long Ahtna Glacier and the smaller Center and South MacKeith glaciers began to advance in the early 1960s and have advanced steadily at rates between 5 and 18 m yr-1 since then. These three glaciers flow from the summit caldera of ML Wrangell near the active North Crater, where increased volcanic heating since 1964 has melted over 7 x 107 M3 of ice. We suspect that volcanic meltwater has changed the basal conditions for the glaciers, resulting in their advance. In College Fjord, Prince William Sound, the terminus fluctuations of two tidewater glaciers have been monitored since 1931 by terrestrial surveying, photogrammetry, and most recently, from satellite imagery. Harvard Glacier, a 40-kmlong tidewater glacier, has been advancing steadily at nearly 20 m yr-1 since 1931, while the adjacent Yale Glacier has retreated at approximately 50 m yr-1 during the same period, though for short periods, both rates have been much higher. This article is from 'Proceedings of the International Conference on the Role of the Polar Regions in Global Change Held in Fairbanks, Alaska on 11-15 June 990. Volume 2', AD-A253 028, p519-523. See also Volume 1, AD-A253 027.