CLASSIFICATION OF METEOROLOGICAL FILED PATTERNS THAT CAUSED HEAVY RAINFALL IN SOUTHERN KYUSHU USING SELF-ORGANIZING MAP

Abstract

 In this study, the Self-Organizing Map (SOM) was applied to the meteorological data from 1954 to 2020 to classify the patterns of the meteorological field in the South Kyushu region. In addition, the heavy rain indexes of each unit were created by using the analytical precipitation data from 2006 to 2020. As a result of classifying 32,696 meteorological fields into 900 units and 55 groups, heavy rain disasters caused by typhoons were classified into neighboring groups around one group. On the other hand, heavy rain disasters caused by the seasonal rain front were widely classified, but the groups in the heavy rain disasters in the Kuma River basin and the groups in the heavy rain disasters in Kagoshima prefecture were different. By comparing the characteristics of the meteorological fields of the heavy rain of July 2020 and July 1965, which caused flood damages to the Hitoyoshi region of Kumamoto prefecture, the behaviors on the SOM of the meteorological fields corresponding to the time were different. It was observed that both meteoro-logical fields were in the same pattern when the rain was the heaviest.