Inversion Methods of Three Cumulus Parameterizations for Diabatic Initialization of a Tropical Cyclone Model

Abstract

Abstract To generate convective precipitation consistent with observations at the beginning of a forecast with an atmospheric prediction model, the irrotational circulation and moisture fields must be initialized properly for dynamical balance with the input rotational and mass fields. This article describes a diabatic initialization procedure for a tropical cyclone forecast model, including the adjustment of the input moisture field with the use of “observed” precipitation data from satellites. The condensation heating rate estimated from “observed” precipitation data and the radiative heating rate calculated from the input data are used as the diabatic heat source to calculate the balanced irrotational wind field using a diabatic nonlinear normal mode initialization algorithm. The adjustment of the moisture field is performed by the inversion of cumulus parameterization, knowing the input precipitation rate. The inversion methods of three cumulus parameterization schemes are presented. The three cumulus...