[A-CG43] Water and sediment dynamics from land to coastal zones

[ACG43-11] Remote transport of riverine water in the Japanese coastal region

*Shota Katsura¹, Hiroyasu Hasumi¹, Yoshimasa Matsumura¹, Masao Kurogi², Takashi T Sakamoto³, Takao Kawasaki¹, Yasuhiro Hoshiba¹ (1.Atmosphere and Ocean Research Institute, The University of Tokyo, 2.Japan Agency for Marine-Earth Science and Technology, 3.Ocean Eyes Co., Ltd.)

Keywords:Riverine Water, Coastal Region, Ocean Model, Particle Tracking

Rivers transport freshwater and materials from land areas to ocean and affect ocean dynamics and environment. However, processes of riverine water transport from coastal regions to open ocean is still not well understood. We focused on the region around Tsugaru Strait where ocean water transported from the Sea of Japan to the Pacific and investigated riverine water transport by particle tracking using high resolution ocean model around Japan. Most part of riverine waters around Tsugaru Strait were distributed within shallow coastal regions and occupied 1-5% of coastal water volume. Pathway of the riverine waters originated from the Sea of Japan side of Honshu Island reflected the seasonal variability of the Tsugaru warm current: Riverine waters were advected eastward in summer while they were transported southward along the coast in the other season. Riverine waters from the Sea of Japan side of Honshu Island were remotely transported to the Pacific side and occupied 0.1-0.5% of water volume in the coastal regions along the Pacific side of the northern Honshu Island.