Characteristic analysis of precipitation events in Changsha city based on minute rainfall data

Using minute precipitation data from 1980 to 2017 of Changsha, the sensitivity of changes in precipitation events with time interval was experimented. On the basis of the establishment of precipitation interval 240 minutes, the characteristics of precipitation events in Changsha were analyzed for five aspects including the rainfall occurrence and amount, the start time, end time, duration, and break interval from March to November, March to June, and July to September. The analysis shows that there are about 121 precipitation events from March to November and 68 precipitation events from March to June and 32 precipitation events from July to September. The start time and end time of precipitation events show different daily variation characteristics with different seasons and rainfall thresholds. The duration for most precipitation events is less than one hour and 76% is below 12 hours. The frequency of events with break interval less than 12 hours is about 46%. Precipitation events lasting over 24 hours account for about 39%.