Patterns and Changes of Precipitation Field Induced By Typhoon in Chinese South Coast Area

Typhoon is one of the severe weather systems bringing heavy rainfall, the storm caused by typhoon landing can result in devastating flood, and cause huge loss to people's lives and property. For example, Typhoon Hato, the strongest typhoon landed south coast of China in 2017 up to now, storm surge in coastal areas of Pearl River estuary reached 50cm to 310cm, 16 people died and a direct economic loss of 12.18 billion Chinese Yuan in Mainland China was estimated. According to the past records, there is an annual average typhoon landfall in this area. Patterns and changes of precipitation field induced by Typhoon in this area is very important for flood forecasting and emergency management, but are less studied. Purpose of this study is to analyze the temporal and spatial features of precipitation induced by Typhoon landed in the south coast area in the past years, and to find its changes. In this presentation, Typhoons landed in this area were selected first, and 10 events were studied. Precipitation estimated by the PERSIANN system, which calculates the precipitation based on the satellite observation with global coverage at hourly interval was used for this analysis. Precipitation from high dense rain gauge network is also acquired for assisting this analysis as it is only available in recent years. Several features/index were analyzed, including radius, moving speed, rainband and intensity, precipitation index that is defined as the strength of precipitation considering several features. Results show that the precipitation patterns are different significantly among typhoons in the past decade, though the change could not be reorganized due to limited typhoon events.