Drought Hazard Analysis in the Jilin Province Based on a Three-Dimensional Copula Method

Based on the precipitation and potential evapotranspiration at 23 stations in Jilin Province, standardized index (SPEI) was calculated. run theory combined with previous research we redefine drought threshold, three characteristics, that is, duration, intensity, severity, were identified extracted. Two- three-dimensional copula functions selected to fit combine variables calculate joint recurrence period. In order make alternative model more complete, 25 representative are for first time construct Joint probability distribution function. The Mann–Kendall test used examine abrupt changes Meihekou County. SPEI trends cumulative of Changbai area analyzed. results show that: (1) unstable around 2000 2010, change points; (2) trend Mountains indicates occurrence is similar various timescales; range duration increase increasing timescale; (3) correlation between strong good. two- period calculations similar, a high within years.