Based on the moist potential vorticity (MPV) theory,this paper analysed the vertical and horizontal components of MPV,MPV1 and MPV2,on 700hPa for the torrential rain process occured during 5 - 6 July, 1991 in the Changjiang-Huaihe Basin.
further more,the analysis of wet potential vorticity indicates that heavy rainstorms are more likely to occur while the vertical component of moist potential vorticity being less than 0 and the vertical component of moist potential vorticity at the isobaric surface being greater than 0 near 700 hPa.
In this paper, the fine grids model of 21 layers and η coordinate is used to simulate a continuing heavy rain in the Wuhan region in July 19-22 ,1998 . The results of model output have used to diagnose moisture potential vorticity for showing its mesoscale characteristics on temporal and spatial.
Using MM5 numerical model, The “ 12.7” strong snow process occurred in Beijing is diagnosed on mechanism. The results show that there is obvious correlation between the snow area and moist geopotential vorticity on 500Hpa.
The main factors of the change of moist potential vorticity are the vertical and horizontal divergence of moist potential vorticity flux as well as the vertical transport caused by the cumulus mass flux.
A diagnostic study of moist potential vorticity generation in an extratropical cyclone
Moist potential vorticity (MPV) and its generation may be important in the development of mesoscale structures such as rainbands within cyclones.
Moist potential vorticity can be generated through the combined effects of gradients in the potential temperature and moisture fields.
(3) The formation and development of meso-β-scale rainstorms under the background of the East-Asia atmosphere circulation are diagnosed with the variation of MPV (moist potential vorticity) anomalies.