COUPLED PHYSICAL-ECOLOGICAL MODELLING OF THE CENTRAL PART OF JIAOZHOU BAY I. PHYSICAL MODELLING

Sharples's 1-D physical model, employing tide-wind driven turbulence closure and surface heating-cooling physics, was used to simulate the evolution of seawater temperature in the central part of Jiaozhou Bay. The results were consistent with observation after application of a large value of vertical eddy diffusivity to the upper layer in the case of rainy season. The simulated bottom seawater temperature varies regularly in sinusoidal pattern. The simulated surface seawater temperature clearly indicates that stratification begins in the middle of April, lasting about 6 days, and ends in later August, lasting only 2 days; and that the strongest stratification occurs in June, when the surface net heat flux is close to zero. Since the rainfall process not considered in the present model could cause very strong vertical mixing in the upper layer of bay water, the physical meaning of applying a larger vertical eddy diffusivity is supposed to be a parametrization of the rainfall created mixing in the upper layer. To prove this hypothesis more complex models have to be used and more observations have to be made in future study. Key words physical modelling - rainfall created mixing in the upper sea - the central part of Jiaozhou Bay Contribution No. 3773 from the Institute of Oceanology, Chinese Academy of Sciences.Project 39630060 supported by NSFC.

Sharples’s 1 D physical model, employing tide wind driven turbulence closure and surface heating cooling physics, was used to simulate the evolution of seawater temperature in the central part of Jiaozhou Bay. The results were consistent with observation after application of a large value of vertical eddy diffusivity to the upper layer in the case of rainy season. The simulated bottom seawater temperature varies regularly in sinusoidal pattern. The simulated surface seawater temperature clearly indicates that stratification begins in the middle of April, lasting about 6 days, and ends in later August, lasting only 2 days; and that the strongest stratification occurs in June, when the surface net heat flux is close to zero. Since the rainfall process not considered in the present model could cause very strong vertical mixing in the upper layer of bay water, the physical meaning of applying a larger vertical eddy diffusivity is supposed to be a parametrization of the rainfall created mixing in the upper layer. To prove this hypothesis more complex models have to be used and more observations have to be made in future study.