OBSERVATION OF TIDAL EXCHANGE DYNAMICS FROM SURFACE CURRENT MEASUREMENTS USING UNMANNED AIRCRAFT SYSTEMS

Coastal transport processes are fundamental to oceanic biogeochemical cycles, sediment dynamics, and pollution management. Surface-associated material transport in coastal settings, including the fate of floating marine contaminants such as oil spills and harmful algal blooms, is heavily controlled by ocean surface currents, together with wave action. During tidal exchange, ocean currents are one of the key parameters that affect whether these surface pollutants may be transported in or out of the bay and estuary through tidal inlets. Thus, practical measurements of ocean surface currents are important to predict many coastal transport processes effectively. However, observation of these transport processes requires large-scale current mapping in the spatial domain to fully resolve the governing mechanisms. In the present study, we utilize an unmanned aircraft systems (UAS) wave-based current mapping technique introduced by Streßer et al., 2017 to visualize the flow structures of the tidal exchange through the Galveston Bay inlets, TX, in high spatial resolution, using a consumer-grade UAS for imaging the ocean surface.