Measuring Complex Beach-Dune Morphology and Nearshore Process using UAVs

Mel Rodgers, University of South Florida
Mathieu Vallee, University of South Florida
Ping Wang, University of South Florida
Jun Cheng, University of South Florida

Abstract

We examined various applications of widely available and low-cost Unoccupied Aerial Vehicles (UAVs) in measuring beach morphodynamics and hydrodynamics. With adequate ground control points, UAVs demonstrate promising potential for capturing highly 3-dimensional beach/dune morphology with cm-scale accuracy and mm-scale resolution. Model accuracy and resolution are also controlled by flight altitude, with lower altitude yielding higher accuracy and resolution but at the expense of less spatial coverage. The time-series of UAV images and DEMs provide a valuable tool to document morphology changes of irregularly shaped coastal features, vegetation coverage and spatial distribution of sediment sizes. The efficiency of UAV data collection allows regional scale pre- and post-storm surveys to quantify storm-induced beach/dune changes. The overhead videos from the reasonably stable platform allow measurements of dynamic surf-zone parameters including incident breaking and non-breaking wave angles, limits of uprush and downrush, swash velocities and longshore current velocity. UAVs prove to be a promising addition to the traditional methods for measuring beach morphodynamics and hydrodynamics.