East Asia and Western Pacific METEOROLOGY AND CLIMATE

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February 1979. It clearly indicates that a cyclone developed to the
northeast of Taiwan, i.e. in East China Sea.The downward motion
intensified in the cold region during the cyclogenesis. As shown by Shapiro
(1981), frontogenesis can be expressed as a purly ageostrophic process
which evolves much faster than the quasi-geostrophic process. The
dynamics of ageostrophic transverse circulation will be discussed in the
next section.
4. DYNAMICS OF THE TRANSVERSE CIRCULATION
The charecteristics of frontal structure depends upon the transverse
circulation in the vicinity of frontal zone. So, the generation of vorticity in
the y-z plane will be discussed.
The x-direction component of vorticity and the vorticity equation
can be expressed as
( w) = - ( v w ). ( + + + - ( + )
at ay az a y az a z p 2 Va z a y a y az v }
where p is the density, p is the pressure, f is the Coriolis parameter and
(u,v,w) are the wind components in (x,y,z) respectively.
Eq.(2) and (3) can be transformed into the p-coordinate as
8v pg 303 i 1 \/y 30 . do) \J\Af