Recent Surge on Steele Glacier in Yukon, Canada, revealed by multi-satellite images
Abstract
Glacier surge is a periodical orders-of magnitude speed-up event during a short active phase, accompanying terminus advance and generation of heavy crevasses on the surface. Near the border of Alaska and Yukon, Canada, there are numerous surge-type glaciers, and their behavior has received a good deal of scientific attentions. To date, the dynamics have been examined at some surge-type glaciers, but there remain some questions about the generation mechanism. High-quality images of recent satellites have allowed us to capture the evolutions of surging episodes with higher temporal resolution. Steele Glacier in the southwest Yukon is one of the recently activated surge-type glaciers after the quiescence of 50 years. It experienced a full surge in 1965-1966. The total ice displacement was about 9.5 km, and the peak speed was about 24 m d-1 (Stanley, 1969). The thermal structure was examined after the surge, which indicates the surge mechanism is thermal controlled (Clarke and Jarvis, 1976). However, the details of the surging evolution remained unclear. Here we report the spatial and temporal variations of the recent event for the first time in 50 years. Using ALOS/PALSAR and Landsat images, we found the latest surge that might initiate between 2011 and 2012, which has been still undergoing. The observed maximum speed was greater than 20 m d-1 in early summer 2015, whereas the quiescent speed was 0.4 m d-1 between 2007 and 2011. It has slowed down to 6 m d-1 in summer 2016. Moreover, based on the ice thickness changes and the moraine movements, the surge seems to have started at the confluence between Steele and Hodgson Glaciers. We have considered that the hydrology and the bed topography at the confluence may be a key to understand the surge generation mechanism.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.C51E..01A
- Keywords:
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- 0720 Glaciers;
- CRYOSPHEREDE: 0758 Remote sensing;
- CRYOSPHEREDE: 0774 Dynamics;
- CRYOSPHEREDE: 0794 Instruments and techniques;
- CRYOSPHERE