Long-term Change and Variability of Precipitation at Tsu City

Long-term change and variability of monthly or seasonal precipitation at Tsu were analysed with data for 101 years. Coefficient of variation of monthly precipitation is very large and ranges 39 to 72%. Spectrum analysis method was applied to detect periodicity of monthly or seasonal precipitation, indicating the existence of 10-year period for August and December and 20-year period for July and November. An empirical relation was obtained for predicting the probability of exceedance of occurrence of continuous drought for summer months.