The recent record-breaking Laurentian Great Lakes water levels have led to severe erosion along many shorelines, but quantification of this erosion has not yet been widely reported. In this paper, novel shoreline measurements of Lake Michigan erosion, using a LiDAR-equipped unmanned aerial vehicle (UAV). The vehicle surveyed two beaches, Dune Acres and Beverly Shores, along the Indiana shoreline of southern Lake Michigan over the period 2018–2019, which are compared to existing aircraft-based LiDAR surveys. The UAV surveys reveal extensive shoreline erosion and recession at both beaches since the low water conditions of 2012–2013, with both beaches losing 70.7 and 64.8 m³/m of dry beach volume. Shoreline recession over this period was nearly 35 m for both beaches. In the period 2018–2019, the UAV measurements reveal continued beach erosion and the transition of beach topography to a steep, actively eroding foredune. Storm erosion resolved by short-interval surveys highlight the episodic nature of shoreline erosion, with 8 m³/m of material lost over a stormy two-week period at Dune Acres. While large, the erosion and recession observed at both beaches is in keeping with limited historical observations of shoreline change during high water episodes. However, the observed overall shoreline recession slopes of 1:29 (water level rise : recession) are much less than historical slopes, suggesting that the beaches are not yet in equilibrium with the high water levels and that erosion will continue in the foreseeable future while lake levels remain high.

最近破纪录的劳伦斯大湖水位导致许多海岸线严重侵蚀，但尚未广泛报道这种侵蚀的量化。在本文中，使用配备 LiDAR 的无人机 (UAV) 对密歇根湖侵蚀进行了新颖的海岸线测量。该车辆在 2018 年至 2019 年期间调查了密歇根湖南部印第安纳州海岸线沿线的两个海滩，沙丘英亩和比佛利海岸，并将其与现有的基于飞机的 LiDAR 调查进行了比较。无人机调查显示，自 2012 年至 2013 年的低水位条件下，两个海滩都出现了广泛的海岸线侵蚀和衰退，两个海滩的水量减少了 70.7 和 64.8 m ³/m 干海滩体积。在此期间，两个海滩的海岸线衰退接近 35 m。在 2018 年至 2019 年期间，无人机测量显示持续的海滩侵蚀和海滩地形转变为陡峭、侵蚀活跃的前缘。短间隔调查解决的风暴侵蚀突出了海岸线侵蚀的偶发性，8 m ³在沙丘英亩的两周暴风雨期间损失了 /m 的材料。虽然规模很大，但在两个海滩上观察到的侵蚀和衰退与高水位期间海岸线变化的有限历史观察结果一致。然而，观察到的海岸线整体后退坡度为 1:29（水位上升：衰退）远小于历史坡度，表明海滩尚未与高水位平衡，在可预见的未来侵蚀将继续，而湖水位居高不下。