Cross-shore topographic survey data for the areas of Dillingham and Chevak Alaska between 2016 and 2025

The Polaris Project (https://arcticpolaris.org/) examines how communities in Arctic Alaska are affected by environmental hazards and changing conditions, including coastal erosion and flooding, declining sea-ice cover, and shifts in the availability and access to wild resources. The project is conducted in partnership with the rural communities of Dillingham in the Bristol Bay region and Chevak in the Yukon–Kuskokwim Delta, and is supported by the National Science Foundation (Award 1927827).
A warming Arctic is accelerating coastal hazards, driving substantial ecosystem change and threatening infrastructure and subsistence lifeways. Identifying and mapping recent erosion is essential for planning and mitigation in western Alaska. Field campaigns were conducted to collect high-resolution coastal datasets documenting storm-driven flooding and shoreline change. Cross-shore profiles were surveyed using a Trimble real-time kinematic global navigation satellite system (RTK-GNSS), extending from upland features to the waterline and repeated over time to measure coastal change.
Repeat profiles reveal significant erosion in both study areas. In Dillingham, surveys conducted between 2016 and 2025 document more than 100 meters of shoreline retreat at some locations, with rates reaching 3.5 meters per year. In Chevak, erosion between 2022 and 2024 averaged approximately 1 meter per year. These combined datasets show a clear and ongoing trend of coastal retreat that can now inform local planning and decision-making. All project results have been provided to Tribal and City governments to support adaptation and preparedness efforts.

北极星项目（Polaris Project，https://arcticpolaris.org/）聚焦阿拉斯加北极地区社区受环境灾害与环境变化的影响，包括海岸侵蚀与洪涝、海冰覆盖减少，以及野生资源可获得性与获取途径的变化。该项目与布里斯托尔湾（Bristol Bay）地区的迪灵汉姆（Dillingham）以及育空-库斯科奎姆三角洲（Yukon–Kuskokwim Delta）的切瓦克（Chevak）的乡村社区合作开展，并得到美国国家科学基金会（National Science Foundation，Award 1927827）的资助。
变暖的北极正在加剧海岸灾害，推动生态系统发生显著变化，并威胁基础设施与传统生计方式。识别并测绘近期的海岸侵蚀状况，对于阿拉斯加西部的规划与减灾工作至关重要。研究团队开展野外考察，采集了记录风暴驱动洪涝与岸线变化的高分辨率海岸数据集。使用天宝（Trimble）实时动态导航卫星系统（real-time kinematic global navigation satellite system, RTK-GNSS）测量跨岸剖面，该剖面从高地延伸至水岸线，并随时间重复测量以追踪海岸变化。
重复测量的剖面显示两个研究区域均存在显著侵蚀。在迪灵汉姆，2016年至2025年间开展的测量显示，部分地点的岸线后退超过100米，年侵蚀速率达3.5米。在切瓦克，2022年至2024年间的平均侵蚀速率约为每年1米。这些整合后的数据集清晰展现了持续的海岸后退趋势，如今可为当地规划与决策提供参考。所有项目成果已提交至部落与城市政府，以支持适应与防灾工作。