Title: From Multiyear Arctic Pack Ice to Predominantly First-Year Sea Ice Cover: Implications of the Changing Sea Ice Cover on Storm Impacts in the Western Canadian Arctic
Mathew Asplin, University of Victoria, Department of Geography
Thursday, November 1st, 2018
Snacks/Discussion begin at 15:15, Talk at 15:30
Location: The Welcome Centre Room, University Centre (Mystic Market)
Abstract
The Arctic sea ice is in transition from consisting of largely multiyear ice cover to one predominantly featuring first-year sea ice. This shift is being driven by increasing energy inputs to the Arctic climate system, coupled with changing dynamic processes in sea ice and large-scale atmospheric circulation features. The Arctic Ocean is increasingly becoming a marginal ice zone, containing thinner and increasingly mobile sea ice throughout the annual cycle. Large expanses of fetch are occurring regularly within the Beaufort, Chukchi, Laptev and Kara seas, which increase potential for large, energetic, and damaging waves that can propagate deep into the pack ice, causing flexural fracture within large ice floes. Coastal ecosystems and communities along the Canadian Arctic coastline are increasingly vulnerable to the risk of damaging storm surges. Storm-driven changes in water levels can result in coastal flooding, increased wave erosion, and low-water levels (negative surge) that can introduce hazards and challenges to shipping and transportation. While coastal ecosystems are dependent on frequent sedimentation and salinization from small floods, larger storm floods can cause salinization of freshwater ponds and non-saline meadows, damage vegetation along the margins of permafrost plateaus, melt subterranean permafrost causing underground hollows subject to collapse (thermokarst), and affect village infrastructure.
This presentation will present key results from field observations of the changing Arctic ocean-sea ice system in the Western Canadian Arctic since 2007. Results are augmented with information obtained from northern residents during community visits conducted at Tuktoyaktuk, Sachs Harbour and Ulukhaktok in April 2018. Residents were asked to describe impacts of sea ice decline, increasing wave action, and storm surges upon their respective communities.