Extended interpretations in Q vector analyses and applications in a torrential rain event

摘要

Theoretical derivation shows that the curl of Q vector is associated with vertical variations of the vertical vorticity of ageostrophic wind. It may provide more information about distributions and evolutions of convective system along with the conventional usage of the divergence of Q vector in operational weather forecast. Therefore, a new phrase - extended interpretations in Q vector analyses - is defined in this paper, which represents the usages of the vertical component of the curl of Q vector as well as its divergence. Through dynamic identifications of both spatial distributions and temporal variations of heavy rain centers of a torrential rain event, advantages in the application of the vertical component of the curl of Q vector over its divergence are evident. In addition, the potential usage of the curl of Q vector in quantitative analysis of ageostrophic motions is pointed out.