Vulnerability of coastal infrastructure in the Arctic: A focus on the historic settlement on Herschel Island

• Main Authors: Radosavljevic, Boris, Lantuit, Hugues, Fritz, Michael, Overduin, Paul, Krautblatter, Michael
• Format: Conference Object
• Language: unknown
• Published: 2013
• Subjects: Arctic; Herschel Island; The Spit; Yukon; Herschel
• Online Access: https://epic.awi.de/id/eprint/34593/; https://epic.awi.de/id/eprint/34593/1/RadosavljevicArcticNet2013.pdf; https://hdl.handle.net/10013/epic.42801; https://hdl.handle.net/10013/epic.42801.d001

Herschel Island has a long history of human habitation by indigenous peoples, and whalers who came to the island at the end of the 19th century. Their traces include many archeological sites, and some of the oldest standing buildings in the Yukon, built during the whaling era. The island has been a territorial park since 1987, and it is a candidate to become a UNESCO World Heritage Site. The historic settlement, airstrip, and park infrastructure are located on Simpson Point, a narrow gravelly spit with elevations generally <2 m. Changing climate conditions and sea level rise are known to threaten the island infrastructure: buildings had to be moved inland, and one was lost completely. This study used a comparison of historic aerial photographs, and a digital elevation model (DEM) created from LIDAR and bathymetric surveys to assess historic shoreline movement, and flood vulnerability to examine the coastal hazard potential on Simpson Point. Field observations and a high-resolution bathymetric survey provided insight into nearshore sediment transport processes. Flood risk was evaluated with LIDAR data from 2013. The volumetric requirements for spit growth were obtained from combining bathymetric and airborne data into a DEM. Retreat is the only viable strategy to preserve the historic settlement. It remains unknown for how long Simpson Point will retain its historic nature. Shoreline retreat affects most of the peninsular shoreline. Decision makers should consider that the Simpson Point vulnerable to storm surge, expected to increase both in frequency and severity, because the low topography of the spit does not offer much protection of flooding by storm surge. Buildings should be raised and moved away from the eroding shore. Ice transport processes such as pile- and push-up, could both be either a benefit or a risk. Encroachment of these processes on shore may destroy infrastructure, but may also supply sediment to the shoreline, thus protecting it from wave attack and storm surge. Overall, the eventual roll-over of Simpson Point as a result of storm overwash is likely.