Detailed Analysis of A Tropical Cyclone Simulated with a 13-Layer Model

Abstract

A numerical experiment for the study of the development and the structure of tropical cyclones is performed with a 13-layer model.

The role of cumulus convection in hurricanes and its representation in hurricane models

“…The earliest schemes to parameterize cumulus convection in numerical models include those of Kuo [1965], Pearce and Riehl [1969], Yamasaki [1968aYamasaki [ , 1968b, Rosenthal [1969], and Ooyama [1969]. Prior to these studies a number of attempts were made to represent latent heat release explicitly; these attempts are re- …”

“…As in the Kuo schemes, convection occurs only in the presence of lowrlevel convergence (w6 > 0) and conditional instability for surface air parcels (T c > T• Yamasaki [1968aYamasaki [ , 1968b used a similar scheme in a four-layer model, again with the total heating in a column proportional to the vertical velocity at the top of the friction layer and its vertical distribution prescribed. In addition, all the moisture entering the column falls out as precipitation.…”

“…Yamasaki [1968a] examined the development of cyclones as the time-independent ratio of heat release between the upper troposphere and lower troposphere was varied and found a sensitivity to this ratio. This sensitivity was explored further by Yamasaki [1968b], where the ratio was allowed to vary with time in proportion to the difference between the potential temperature of the mean field and that of the parameterized clouds. Schemes similar to that of Rosenthal [1969] were used by Kitade [1980], who modified the rate at which the convection moistens the atmosphere, and Madala and Piacsek [1975], who developed a three-dimensional three-layer hurricane model on a [• plane.…”

On the Convection in a Conditionally Unstable Atmosphere with Mean Vertical Motion

“…Ooyama (1963), Charney and Eliassen (1964) proposed a model of the development of a tropocal cyclone in which they gave the activity of cumulus convections in proportion to the frictionally induced convergence to account for the concentration of moisture in the low-level in low latitudes. The numerical simulation of typhoon development using this model seem to be remarkably successful (Yamasaki (1968), Ooyama (1969), etc. ).…”

A quasi-empirical model of the hurricane boundary layer

“…A number of axisymmetric vortex models (e.g., Yamasaki, 1968a and1968b;Ooyama, 1969;Rosenthal, 1971) have been developed to describe the evolution of the intense wind region characteristic of hurricanes. The specified initial conditions are mainly designed to insure low-level inflow, so that the vortex will eventually become unstable, and are not related to observations.…”