Three years of weekly DEMs, aerial orthomosaics and surveyed shoreline positions at Waikīkī Beach, Hawai‘i

Abstract

In this dataset, we present 128 coastal surveys conducted between 2018 and 2021 at Kahaloa Beach, also known as the Royal Hawaiian Beach, in Waikīkī, Hawai‘i. Surveys were conducted on a near-weekly basis, providing a 0.5 m digital elevation model, an orthorectified image mosaic with 0.03 m resolution, and shoreline vectors at MHHW and MSL, along with a surveyed shoreline position for each survey. We captured overlapping images using a small Unoccupied Aerial System (sUAS), processing the imagery with photogrammetric software to produce orthomosaics and Digital Terrain Models (DTM). Simultaneously, the shoreline position and reference points for sUAS-derived products were surveyed using total station and rod-mounted surveying prism. A quality assessment of 424 randomly sampled points across two surveys showed normally distributed errors of DTM elevations (µ1 = 0.0060 m; σ1 = 0.0998 m; µ2 = 0.0035 m; σ2 = 0.0680). Elevation uncertainties were quantified as 95% confidence intervals (±0.0130 m and ±0.0095 m). These data are intended to encourage research on reef-fringed beaches and provide a dataset for evaluating the accuracy of satellite-derived shorelines at reef-fringed beaches.