1. Physical Oceanography Laboratory, Department of Physics and Earth Sciences, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara 903-0213, Japan
2. Coastal Processes Research Group, Research Center for Oceanography, National Research and Innovation Agency (BRIN), Jakarta 14430, Indonesia
3. Department of Oceanography, Faculty of Fisheries and Marine Science, Diponegoro University, Semarang 50275, Indonesia