Arctic-subarctic coastal hazards and morphodynamics (AsCHMor)

沿海风暴在不同程度上塑造海岸线，每年影响数百万人。尽管在南方国家进行了广泛的研究，但在北极，人们对风暴的影响仍然知之甚少，因为在偏远的沿海地区很难进行高频测量。尽管如此，沿海地区的变化仍在影响着因纽特人社区，并因永久冻土融化和海冰减少而加剧。后者进一步增加了浪高。北极和亚北极地区的极端海岸事件可能是由高水位和海浪共同造成的，要么是在开阔的水域，要么是在结冰的水域。低温过程和危害包括海冰冻结/破裂、冻融循环和冰推脊。整个北极地区不同的均衡调整也导致了不同的海平面变化，模糊了海岸侵蚀和洪水的影响。我们假设，冰冻沉积物也控制海岸冲过过程，这是海岸管理的一个主要问题。因此，在冰冻的海岸上，预测海岸的长期演变并非易事。北极-亚北极海岸灾害和形态动力学（AsCHMor）研究项目的目标是显著提高我们对北极-亚北极地区海岸形态动力学的理解，增强我们在气候变化和人类对海岸压力增加的影响下模拟和预测未来海岸行为的能力。该计划的目标是北极很少探索的沿海灾害的两个组成部分。首先，AsCHMor将实施(i)，以更好地了解加拿大北部社区在高能风暴期间冲刷带的海滩沉积物渗透率和孔隙冰饱和度之间的复杂相互作用。（ii）第二个组成部分综合了在区域和地方尺度上探索和应用覆冰水域沿海总水位的经验/数值模型，以提高我们的风险管理能力。AsCHMor将通过大量的观测、建模和技术开发，在整个迭代过程中实现。11名HQP（5名理学士，4名理硕士，2名博士）将在亚北极和高北极沿海社区（圣劳伦斯河口，哈德逊湾，琼斯湾）进行实地工作。利用我以前的作品，一个由国内和国际合作者设计的新型岸基视频网络将被部署。这一建议是独特的，对于改善北极沿海动态和危害方面的知识差距是必要的。它的实施将通过为快速发生的沿海灾害情况提供新的预测工具而使北方社区受益。它将通过科学研究和监测增加社区决策的自主权。AsHCMor的长期目标是加强加拿大北部的预报服务和早期预警，并为北部社区的疏散和适应战略及时提供有效的信息。

Coastal storms shape coastlines at various scales and affect millions of people annually. Although widely studied in southern countries, storm impacts are still poorly understood in the Arctic because high-frequency measurements are hardly feasible on remote coasts. Coastal changes are nevertheless affecting Inuit communities, and are enhanced by permafrost thaw and sea ice reduction. The latter further contributes to increased wave heights. Extreme coastal events in arctic and subarctic regions are presumably caused by combined high water levels and waves, either under open or ice-infested waters. Cryogenic processes and hazards involve sea ice freeze/break-up, freeze-thaw cycles, and ice push ridges. Varying isostatic adjustments throughout the Arctic also result in contrasting sea-level variations that blur the impacts of coastal erosion and flooding. We hypothesize that frozen sediments also controls coastal overwash processes, and this is a primary concern for coastal management. On frozen coasts, it is therefore not trivial to predict coastal evolution in the long term. The objective of the Arctic-subarctic coastal hazards and morphodynamics (AsCHMor) research program is to significantly improve our understanding of coastal morphodynamics in the arctic-subarctic region and to enhance our capacity to simulate and predict future coastal behaviors under the impacts of climate change and increasing human pressure on the coast. The program targets two components of coastal hazards rarely explored in the Arctic. First, AsCHMor will be implemented (i) to better understand the complex interactions between beach sediment permeability and pore-ice saturation in the swash zone during energetic storms in northern Canadian communities. (ii) The second component integrates the exploration and application of empirical/numerical models of coastal total water levels in ice-infested waters at both regional and local scales to improve our risk management capacity. AsCHMor will be implemented throughout an iterative process using numerous observational, modeling, and technological development. Eleven HQP (5 B.Sc., 4 M.Sc., 2 Ph.D.) will perform field works on subarctic and High Arctic coastal communities (St. Lawrence Estuary, Hudson Bay, Jones Sound). Capitalizing on my previous works, a novel shore-based video network designed with national and international collaborators will be deployed. This proposal is unique and necessary to improve knowledge gaps in Arctic coastal dynamics and hazards. Its implementation will benefit northern communities by providing new predictive tools on fast-onset coastal disasters situations. It will increase autonomy in community decision-making through scientific research and monitoring. The long-term goal of AsHCMor is to strengthen Canada's forecasting services and early warnings in the north and to provide efficient information on time for evacuation and adaptation strategies in northern communities.