태풍파라미터의 변동과 태풍 바람장의 추산

Abstract

Hindcasting and forecasting of typhoon generated waves and storm surges require the detailed meteorological input such as wind and pressure at each fine grid point and time step of the ocean model. However, it is known that the time and space variation of the typhoon wind is so large that the details of the wind distribution can not be properly provided by surface wind prediction produced by numerical weather prediction model. This paper describes an operational system for determining meteorological forcing by using solutions of simple parametric models that can used for both hindcasting and forecasting of the wave and storm surge for the waters around Korean peninsula.The surface pressure distribution can be conveniently modeled by ideal typhoon as shown in Myers formula. However, when the typhoon is approaching to the higher latitude, the distortion of the symmetric characteristics of surface pressure distribution need to be considered for more realistic prediction of the typhoon wind. The typhoon parameters that are used in estimating typhoon pressure distribution were estimated using surface air pressure measurement data when typhoons were approaching to Korean Peninsula. In open water where in situ. measurement data is not much available, the parameters were estimated by using other available information such as wind measurement by satellite remote sensing. The satellite wind measurement data from various satellite remote sensing such as TOPEX/POSEIDON, JASON, ENVISAT, GEOSAT,ERS and QUIKSCAT were analysed to estimate the typhoon parameters by means of a kind of inverse modeling. Typhoon wind model used in the analysis is the model that can provide a fairly complete description of time-space evolution of the surface winds in the boundary layer of a tropical cyclone(Thompson and Cardone (1996)). Typhoon parameters estimated for various typhoons characterized by different typhoon intensity (center pressure), size, propagating speed, position(latitude),