Spatio-Temporal Variations of Turbulent Energy Dissipation Rate during Stratification Period in Ariake Bay

Abstract

In recent years in-situ measurements on microstructures are carried out to investigate turbulence structures in shallow sea areas. However it is difficult to figure out turbulent structures near interfaces, such as sea beds, sea surfaces and pycnocline, because of the measuring principle of a commonly-used shear sensor. In this study, field observations on microstructures were carried out in Ariake Bay by using the microstructure profiler which acquires fine-scale temperature gradients. As a result of these observations, spatio-temporal variations of turbulent energy dissipation rate in the northern area of Ariake Bay were observed and it is clarified that the way to estimate turbulent energy dissipation rate from temperature gradients in shallow sea areas is valid especially under strongly stratified condition.