Wind effect on currents in a thin surface layer of coastal waters faced open-sea

Nakano, Masanao; Isozaki, Hisaaki; Isozaki, Tokuju; Nemoto, Masashi*; Hasunuma, Keiichi*; Kitamura, Takashi*

Umi No Kenkyu, 18(1), p.37 - 55, 2009/01

https://ci.nii.ac.jp/naid/110007028667

To investigate the relationship between the wind and the current along the coast, the continuous observation of wind and current carried out for two years. The observed area was off shore Tokai-mura in Ibaraki prefecture, where faces open ocean. Considering the existence of strong pycnocline, the observation was carried out at the shallow depth over the pycnocline. The period of wind and current variation for 1 day and over several days was significant. Although the long period variation is caused from the variation of weather and season, the south current is formed by the permanent north wind component. The high correlation factor (0.64) between wind and surface current at 0.5 m was obtained throughout two years. As the result of harmonic analysis, both wind and current variations of 1 day period were appeared as S1 component tide, and it was confirmed to be land and sea breeze, and wind driven current, respectively. The land and sea breeze, which contains solar component except S1, adds the wind driven current except S1 to the corresponding component tide. From these results, it is considered that the land and sea breeze makes the pseudo S1 tidal current to the sea surface in the open coastal sea.