[A-OS15] Ocean circulation and material cycle in coastal seas

[AOS15-07] Observation of a river front using drones

*Kentaro Takami¹, Shinichiro Kida², Atsuhiko Isobe² (1.Kyushu University Interdisciplinary Graduate School of Engineering Sciences, 2.Research Institute for Applied Mechanics, Kyushu University)

Keywords:River front, Drones, Infrared camera, Rotating tank

A river front is known to form between seawater and riverine water. To understand the physical process of river water dispersing to the ocean in coastal areas, it is necessary to clarify the spatial structure and temporal changes of the river front. In this study, we imitated remote sensing observations of a river front using drones by observing the river front reproduced within a rotating tank. The rotating tank is circular and rotates at a constant speed. After introducing river water into the tank, images were taken with a visible camera and an infrared camera from above and with an underwater camera near the outlet. The visible images showed the river water forming a bulge and a flow along the wall that branches off from the bulge. The infrared images showed vortices forming within the bulge. The underwater images showed river water mixing with seawater below. Since bathymetry is often shallow and river water can be in contact with the bottom, we plan to investigate river plumes that are influenced by bathymetry and examine their behavior.