Thermal convection in a closed water body with compound cross section

In a closed water body with compound cross section, we examined the effects of horizontal convection based on the horizontal density difference on the characteristics of thermal convection generated by radiational cooling at water surface. An experiment for measuring water temperature revealed that the fluid exchange was done by the horizontal convection based on the density difference between deep and shallow parts. Moreover, a flow visualization experiment to investigate the characteristics of thermal, which are developmental factors in vertical convection, found that the generation frequency and the generation interval of thermals was higher in the case of compound cross section than the case of even depth. That is, it was understood that the change of the development characteristics of the mixed layer (vertical convection) based on the effect of horizontal convection occurred by the change of occurrence characteristics of the thermals.