降雨の時空間分布特性の地形依存性

Abstract

Taking distribution of the growthdecay rate of rainfall intensity as a random field, we tried to find and model some relations between parameters of the field and geographical features beneath the field. The purpose of the modeling is to eventually create a new methodology for design rainfall. We used a time series of horizontal radar images which were obtained at 5 minute intervals over Kagoshima Prefecture in Japan. The length of the time series is one day. As a result of this research, temporal correlation of the growth-decay rate, for a scale of moving average which is more than 15km, is higher over land area than over ocean indicating a relationship between land forms and rainfall. Next, in regards to the spatial correlation, encouraging results were obtained for the qualitative relationships between the geographical features and rainfall.