GFDLTM-HYCOM 태풍-해양 접합 모델 개발 및 초기 결과

Abstract

By coupling the GFDL Tropical cyclone Model (GFDLTM) and the Northwest Pacific circulation model based on the HYCOM, the Synchronized Typhoon and Ocean Research Model (GH-STORM) is under development. We are going to introduce some progresses in developing the GH-STORM and preliminary results for the two typhoons in 2007: Nari and Usagi. The GFDLTM uses a triple nested movable mesh system to depict the interior structure of tropical cyclones. The model initial condition is defined through a method of vortex replacement. Time integration of the model is carried out by a two-step iterative method that has a characteristic of frequency selective damping (Kurihara et al., 1998). Recently, the GFDLTM had been coupled with POM (Princeton Ocean Model) in the Atlantic Ocean and shows many improvements in the hurricane prediction especially in the intensity with several upgrades (Bender et al., 2007). The GH-STORM follows the same framework of GFDLTM replacing the POM to the HYCOM in the Northwest Pacific. The outer domain covers 75°x75° with 1/2° spacing, the intermediate domain covers 11°x11° with 1/6° spacing and the finest and innermost domain covers 5°x5° with 1/12° horizontal grid resolution. The intermediate and innermost grids are movable following the typhoon.The HYCOM Northwest Pacific circulation model uses a fixed domain covering 115 ~ 150°E, 15 ~ 52°N with a horizontal resolution of 1/12°. Currently the initial and lateral boundary conditions are adopted from the climatological spin-up results of global HYCOM forced by COADS data.Two kinds of typhoons, Nari and Usagi, 2007, have been tested and the results with various sensitivities will be presented.