With projections of accelerating sea-level rise, changing weather and wave regimes and increasing intensity of storm events associated with anthropogenic climate change, the physical persistence and consequently habitability of coral reef islands is a global concern. This study presents an analysis of shoreline changes on 104 coral reef islands from 16 atolls in the western equatorial Pacific nation of the Federated States of Micronesia across a period coincident with rising local sea level and a high frequency of storm events. Aerial photographs from the mid-1940s and 1970s were analysed alongside recent high-resolution satellite imagery to document shoreline changes and planform morphological adjustments in islands. Results revealed accretion has been the predominant mode of shoreline change, with 46% of the studied shorelines showing statistically significant accretion leading to a net increase of 64.37 ha (~3%) of planform land area across the archipelago. Three new islands were formed with a cumulative land area of 2.05 ha, conversely, three islands were completely eroded leading to a loss of net land area of 3.20 ha, providing a record of concurrent island formation and loss within a high storm frequency setting. Reef islands in the FSM demonstrated a range of styles of planform geomorphic adjustments including island rotation, expansion, contraction, spit extension, and migration of islands on the reef platform. Results provide empirical evidence of shoreline accretion despite local sea-level rise as well as of heterogeneity in magnitude and style of geomorphic responses of reef islands across FSM with considerable variability at inter and intra-atoll scales.

随着海平面上升的加速，天气和波浪形式的变化以及与人为气候变化有关的风暴事件强度的增加的预测，珊瑚礁岛屿的物理持久性和可居住性已成为全球关注的问题。这项研究提供了对密克罗尼西亚联邦西太平洋赤道太平洋国家16个环礁的104个珊瑚礁岛海岸线变化的分析，该变化与当地海平面上升和暴风雨事件频发相吻合。分析了1940年代中期和1970年代中期的航空照片以及最近的高分辨率卫星图像，以记录海岸线的变化和岛屿的平面形态调整。结果表明，吸积是海岸线变化的主要方式，研究中有46％的海岸线显示出统计上的显着增生，导致整个群岛的平面土地面积净增加了64.37公顷（〜3％）。形成了三个新的岛屿，累计土地面积为2.05公顷，相反，三个岛屿被完全侵蚀，导致净土地面积减少了3.20公顷，这提供了在高风暴频率设置下同时发生的岛屿形成和损失的记录。FSM中的礁岛展示了多种形式的地貌调整样式，包括岛旋转，扩展，收缩，吐出延伸以及礁平台上岛的迁移。