东海西北部中层冷水垂直热结构数值预报方法研究 Ⅱ.三维数值预报模式

根据含中层冷水海洋垂直热结构的特征,将其分为4层,并考虑来自海面的热力和动力强迫因子、水层界面剪切应力和卷挟热交换、热平流、混合及地形影响等条件下,从原始动量、连续方程组及热传导方程出发,对整个海洋和各水层分别进行垂向积分,导出相应的描述风生界面起伏、各水层平均流场和温度场的闭合方程组.当解得各水层的平均温度场T_k(k=1,2,3,4)后,根据Tk与对应水层界面特征温度间的关系获得后者,最后通过水温剖面表达式获得含中层冷水海洋的三维热结构.为了检验本模式的功能,以时效为5d试报了5月15日研究海域的三维热结构,并将试报结果与实测值进行了比较.结果表明,试报水温的均绝误差为025℃,效果令人满意.

The study on the numerical prediction method for the vertical thermal structure of intermediate cold waterin the northwestern area of the East China SeaⅡ.Three-dimensional numerical prediction model

A ccording to the character istics of vertical thermal structure of intermediate cold water,and considering the sea surface thermal and dynamical forcing factors,the shear stress and entrainment heat exchange in the interfaces of water layers,heat advection,mixing and topographic effect,firstly the closedly relevant equations are derived by vertical integrating whole ocean and each layer,respectively based on primitive momentum,continuity and heat conduction equations.The equations can describe wind-driven interface fluctuation,the mean velocity and temperature fields in each layer.And after solving mean temperature field in each water layer T_k(k=1,2,3,4), the characterizing temperature in each relevant water interface are obtained,on the basis of the relation between T_k and characterizing temperature.Finally,the three-dimensional heat structure of ocean with intermediate cold water is constructed by means of temperature profile expression.In order to verify the function of the model,the trial predictions of three-dimensional thermal structure in the study sea area on 15 May are made by valid time of 5 days. The comparison between the trial results and the measured ones is also carried out.The results show that the mean absolute error of water temperature trial prediction equals 0.25℃,so the results of the trial prediction is satisfactory.