[A-OS21] Coastal ocean circulation and material cycle

[AOS21-04] Wind-induced coastal upwelling along the east coast of the Japan mainland investigated with satellite observation data

*Kaede Shibata¹, Eiji Masunaga¹ (1.Ibaraki University)

Keywords:Coastal upwelling, Chlorophyll-a, Weather satellite Himawari

Vertical transport is important for understanding global ocean circulations and ecosystems. Wind-induced coastal upwelling is one of the major phenomena inducing vertical transport in coastal regions. However, coastal upwelling owing to wind forcing has not been understood along the Japanese coast. This study presents wind-induced coastal upwelling along the east coast of the Japan mainland in summer using satellite observations data observed by Himawari. Sea surface temperature on the east coast decreases as southerly winds increase, hence, typical summer monsoon-induced coastal upwelling appears along the east coast. The magnitude of upwelling greatly depends on the southern wind magnitude, thus, low temperature water mass along the east coast can be explained by wind-induced upwelling. Spatial distributions of upwelling vary within small scale (~ O(10) km). Upwelling is intensified where the wind direction correspond to the coastline. Coastal upwelling along the east coast of Mainland Japan is accompanied by high chlorophyll-a water. In addition, air temperature over land near the coast is likely reduced by coastal upwelling through heat flux toward ocean.