[A-CG48] Water and sediment dynamics from land to coastal zones

[ACG48-P01] Estimating the flow field of river fronts using AUVs

Yusei Umeda¹, *Shinichiro Kida² (1. Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 2.Research Institute for Applied Mechanics, Kyushu University)

Keywords:AUVs, drifting buoys, river plumes

We developed a method for estimating the flow field of river plumes using AUVs. River plumes are often associated with narrow freshwater fronts that form between river water and oceanic water. The detailed process behind mixing across the front is difficult to observe because of its high time variability. Past studies tracked bubbles that often exist along the front, but this approach could not detect the flow field in the surrounding regions. We attempted to capture the flow field by deploying drifting buoys and creating an artificial signal. Observations showed that the flow field can be accurately extracted by using the camera angle information. We plan to increase the number of drifting buoys and vary the drogue depth to estimate the flow fields over a wider area and at different depths.