In this whitepaper, we explore the innovative application of a hovering drone-mounted LiDAR system paired with a survey-grade satellite and inertial positioning system to measure wave transformation and runup in the surf zone. Unlike traditional methods, the multi-rotor small uncrewed aircraft system (sUAS) offers unobstructed measurements by hovering above the surf zone at a 20-meter elevation, scanning a 150-meter-wide cross-shore transect.
This approach allows rapid and precise data collection in remote locations where terrestrial scanning is challenging. Our study demonstrates that hovering drone-mounted LiDAR provides measurement accuracy almost equivalent to a stationary truck-mounted terrestrial LiDAR. By conducting observations in various surf conditions and validating with traditional land-based surveys and pressure sensors, we achieved a stable back beach topography estimate.
We also calculated statistical wave properties, runup values, and bathymetry inversions using a simple nonlinear correction to wave crest phase speed. This method shows the potential of drone-based LiDAR for accurate nearshore process observations, enabling data collection in previously inaccessible sites and providing valuable validation for coastal models.