Spatiotemporal variability of typhoon impacts and relaxation intervals on Jaluit Atoll, Marshall Islands

Storms are important drivers of geomorphic change within atoll settings, causing rapid island erosion while also initiating island building through the generation of vast quantities of reef-derived sediment. Due to the combined effects of storms and sea-level rise, reef islands are thought to be on an erosional trajectory. Jaluit Atoll in the Marshall Islands was struck by Typhoon Ophelia in A.D. 1958, causing significant geomorphic change to reef islands. Using aerial photographs as well as recent satellite imagery we track the impacts of the typhoon and the multidecadal recovery of islands. Ophelia caused a significant reduction in total land area of Jaluit Atoll, from 9.95 km (super 2) to 9.45 km (super 2) (-5.1%), with islands on the northeast rim collectively reducing in size from 4.72 km (super 2) to 4.14 km (super 2) (-12.2%). Between 1976 and 2006, 73 of 87 islands increased in size, with the total landmass exceeding the pre-typhoon area (10.25 km (super 2) ). However, we observe considerable spatiotemporal variability of impacts and relaxation following the typhoon. Results indicate that despite significant typhoon-driven erosion and a relaxation period coincident with local sea-level rise, islands have persisted and grown.