G. Balasubramanian et Mk. Yau, BAROCLINIC INSTABILITY IN A 2-LAYER MODEL WITH PARAMETERIZED SLANTWISE CONVECTION, Journal of the atmospheric sciences, 51(7), 1994, pp. 971-990
A two-layer primitive equation model with a parameterization for slant
wise convection is used to study explosive cyclones. The parameterizat
ion includes a simple representation of the planetary boundary layer,
as well as deep and shallow cloud types. The major results are 1) the
two-layer model produces a realistic explosive cyclone, 2) the explosi
ve deepening coincides with the formation of the ''bent-back warm fron
t,'' 3) fronto-genetic calculations reveal an indirect circulation due
to ''tilting'' in the intense warm front, and 4) the quasi-Lagrangian
heat and vorticity budgets indicate strong interaction of the lower-
and upper-level flow during the rapid spinup stage. These results sugg
est a sequence of events involved in some explosive cyclogenesis: Conv
ection leads to rapid frontogenesis and the formation of a bent-back w
arm front. The sudden surge of cold advection in the regions of the be
nt-back warm front then forces the upper-level heights over the cyclon
e center to fall in a rather dramatic way. Increased upper-level vorti
city advection interacts with the low-level system, leading to explosi
ve cyclogenesis.