垂直涡度方程的比较分析

通过对经典垂直涡度方程、全型垂直涡度方程、新型垂直涡度方程之对比分析,发现由位涡方程出发导出的全型垂直涡度方程存在着不足:(1)在θz=θz=0的中性层结情况下,方程不适用;(2)在一般情况下,全型垂直涡度方程不能准确反映力管项-α×p作用对垂直涡度变化的影响;(3)全型垂直涡度方程高估了倾斜涡度强迫对垂直涡度发展的作用.

Comparison of the Different Forms of Vertical Vorticity Tendency Equation

Vertical vorticity is often used to measure intensity of synoptic system.Vertical vorticity equation is applied to diagnose and analyse the evolution of synoptic system.Meteorologists have been longing for a complete form of vertical vorticity equation that includes not only dynamic elements,but also thermodynamic elements,frictional dissipation and diabatic heating. Such equation will be applicable to three dimensional motion,since traditional vertical vorticity equation is not obviously able to embody effects of thermal and dynamic elements on vertical vorticity,and is appropriate only for horizontal motion.Comparisons among the different forms of vertical vorticity equation are made.The deficiencies of complete form vertical vorticity equation are revealed.It is given a new complete form vertical vorticity equation that is consistent with traditional vorticity equation in essence.Further analysis indicates that complete form vertical vorticity equation overestimates action of Slantwise Vorticity Development(SVD) triggering vertical vorticity change.