ANALYSIS OF THE EMERGENCE TREND OF TYPHOON-LIKE RAINFALL CLUSTERS BASED ON THE ANALYSIS OF MESOSCALE MODEL DATA

Abstract

 We analyzed the occurrence trends of rainfall clusters formed around typhoons based on rainfall analysis data from the Japan Meteorological Agency's MesoScale Model. The possibility of identifying characteristic rainfall clusters by coordinate transformation and binarization was demonstrated. The rainfall clusters decrease with distance from the center of the typhoon, and are more common in the north-northeast direction. The rainfall intensity statistically depends on latitude and central pressure, and the location of the center of gravity of rainfall clusters also depends on the central pressure. The azimuthal angle of rainfall clusters was found to be dependent on the moving speed, latitude, and on the month of onset. Rainfall clusters predominantly move counterclockwise away from the typhoon, but within a radius of 200 km, radial movement is not as pronounced. Additionally, there appears to be a certain level of persistence in the movement of rainfall clusters in the circumferential direction and away from the typhoon at successive times.