AN AUTOMATIC STORM TRACKING METHOD USED TO ANALYZE TRAVELLING CHARACTERISTICS OF HEAVY RAIN AREAS

概要

論文の詳細を見る
A large amount of digital information has been recorded at the various rain gauging radar stations operated by the Ministry of Construction of the Government of Japan. A computer-aided automatic storm tracking method is indispensable for analyzing this bulky MT data. The method reported in this paper automatically traces the centroid of the heavy rain area over a given truncation level. As the truncation level, 16 mm/h was selected, the unit heavy rain area being 2.04 km × 3.4 km and the observation area subject to quantitative analyses having a 102 km radius. The heavy rain areas traced translate to nearly the same directions in the entire 102 km radius area and throughout the duration of a heavy rainstorm, except for typhoons in which the translation directions change as the eye of the typhoon moves. The translation direction is 0° to 10° to the right of the upper layer wind at 700 mb. The lifetimes of heavy rain areas were found to be less than around 20 minutes. From those findings, I concluded that the movement of heavy rain areas can be forecasted by a simple extrapolation method with possible aid from upper layer wind observations, but that the forecast is limited to about 20 minutes unless meteorological dynamics also are considered.
日本自然災害学会の論文