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Progress of Research on Potential Vorticity and its Inversion

In this paper potential vorticity (PV) and potential vorticity inversion (PVI) and their application in the cyclogenesis and mesoscale meteorological phenomena are reviewed. PV has been served as a powerful and useful dynamic tracer for the understanding of the large-scale dynamics and synoptic variations in the atmosphere and oceans. Significant progress has been made on the application of PV in recent decades there has been a substantial amount of work done on PV in a general moist atmosphere. The GMPV is defined for a real atmosphere by introducing a generalized potential temperature instead of the potential temperature or equivalent potential temperature. Such a generalization can depict the moist effect on PV anomaly in the nonuniformly saturated atmosphere. Apart from PV, its inversion theory is also widely accepted as a useful tool in atmospheric diagnostics and numerical forecasting. If the suitable balanced models are chosen, the equations of potential vorticity inversion can be sufficient to deduce, diagnostically, all the other dynamical fields, such as winds, temperatures, geopotential heights, static stabilities, and vertical velocities, under a suitable balance condition. Several common kinds of potential vorticity inversion operators, and the associated balanced models, are introduced in this paper. It is confirmed that the potential vorticity and its inversion theory not only play an important role in studying the evolution and development of weather system, but also would give new content in the present weather forecasting system.