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Abstract The thawing of permafrost in the Arctic has led to an increase in coastal land loss, flooding, and ground subsidence, seriously threatening civil infrastructure and coastal communities. However, a lack of tools for synthetic hazard assessment of the Arctic coast has hindered effective response measures. We developed a holistic framework, the Arctic Coastal Hazard Index (ACHI), to assess the vulnerability of Arctic coasts to permafrost thawing, coastal erosion, and coastal flooding. We quantified the coastal permafrost thaw potential (PTP) through regional assessment of thaw subsidence using ground settlement index. The calculations of the ground settlement index involve utilizing projections of permafrost conditions, including future regional mean annual ground temperature, active layer thickness, and talik thickness. The predicted thaw subsidence was validated through a comparison with observed long-term subsidence data. The ACHI incorporates the PTP into seven physical and ecological variables for coastal hazard assessment: shoreline type, habitat, relief, wind exposure, wave exposure, surge potential, and sea-level rise. The coastal hazard assessment was conducted for each 1 km2coastline of North Slope Borough, Alaska in the 2060s under the Representative Concentration Pathway 4.5 and 8.5 forcing scenarios. The areas that are prone to coastal hazards were identified by mapping the distribution pattern of the ACHI. The calculated coastal hazards potential was subjected to validation by comparing it with the observed and historical long-term coastal erosion mean rates. This framework for Arctic coastal assessment may assist policy and decision-making for adaptation, mitigation strategies, and civil infrastructure planning.
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Field Studies of Megagravel Transport: Relevance for Coastal Infrastructure Engineering
Abstract Extreme wave impacts on coastal infrastructure, including bridges, is a growing problem. Highest energy events are difficult to study because direct observations in real time are almost impossible. Also the non‐linear dynamics are difficult to model or to reproduce in scaled experiments. Coastal boulder deposits incorporating megagravel (y axis >4.1 m) provide natural analogues of infrastructure components such as bridge deck slabs; and field measurements of these wave‐transported blocks can address this knowledge gap. In this contribution we present geoscience data relating coastal topography, wave climate, and dislodgement of megagravel up to 620 tonnes. We hope that this will generate new synergies among coastal geocientists and engineers.
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- Award ID(s):
- 2114016
- PAR ID:
- 10469570
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ce/papers
- Volume:
- 6
- Issue:
- 5
- ISSN:
- 2509-7075
- Format(s):
- Medium: X Size: p. 768-771
- Size(s):
- p. 768-771
- Sponsoring Org:
- National Science Foundation
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