非绝热加热、湿斜压热动力耦合强迫激发辐合增长的一种机制

A MECHANISM OF THE INCREMENT IN CONVERGENCE EXCITED BY THE DIABATIC HEATING AND THE COUPLING FORCES BETWEEN DYNAMIC AND THERMODYNAMIC FIELDS

大气热力状态的非均匀分布及其与动力场的相互作用激发大气动力场发生变化,其事实已被许多数值模拟证实。散度作为度量大气运动辐散、辐合强度的物理量,其变化应受到大气热力状态分布及其与动力场相互作用的影响。然而,在传统的大气动力学理论框架中,并没有从理论上揭示大气热力场分布及其与动力场相互作用对散度场变化的影响。通过对热力学方程做变形处理,并与动力学方程结合,在替换平衡近似下(alternative balance),导出了显式包含非绝热加热分布与垂直风切变相互作用、斜压热动力耦合强迫影响的新型散度方程。利用该方程,重点分析了非绝热加热非均匀分布与垂直风切变相互作用对散度场变化的影响,从动力学理论上初步揭示了非绝热加热分布与垂直风切变相互作用激发大气散度场变化的物理机制。

Based on the fact that diabatic heating is able to excite the evolution of divergence fields,a new type of divergence equation with diabatic heating is obtained starting from the primitive equations.The analysis on this equation brings to The mechanism of the increment in convergence excited by the diabatic heating.Especially,the factor that excites the evolution of divergence fields is the coupling force between inhomogeneous distribution of diabatic heating and vertical shear of wind instead of diabatic heating itself.