TEMPORAL AND SPATIAL VARIATION CHARACTERISTICS OF SIMULATED TYPHOON EWINIAR (2006)

Based on the numerical simulation on typhoon Ewiniar by use of the WRF(weather research and forecasting) model V2.2 and the two way movable nesting technology,the temporal and spatial characteristics of perturbations in Ewiniar has been analyzed briefly by means of power spectrum and maximum entropy spectrum methods.The results show that the long wave component dominates inside the typhoon;the nearer the distance to the typhoon center,the greater the long wave component.However the short wave component increases around the periphery of the typhoon.The oscillation inside typhoon Ewiniar is asymmetrical,the asymmetry is very remarkable at the middle and upper levels of the troposphere and within the eyewall but blur in the outer region of the typhoon and at the low level.The low frequency oscillation dominates in the inner region within typhoon eyewall at the low level.