가뭄해갈 가능성을 고려한 가뭄사상의 결정 및 확률 가뭄심도 산정

Abstract

Paper number: 15-104Received: 24 December 2015; Revised: 23 January 2016 / 2 February 2016; Accepted: 2 February 2016AbstractThe objective of this study is to propose a new method to determine the drought event and the design drought severity. In order to define a drought event from precipitation data, theory of run was applied with the cumulative rainfall deficit. When we have a large a mount of rainfall over the threshold level, in this study, we compare with the previous cumulative rainfall deficit to determine whether the drought is relieved or not. The recurrence characteristics of the drought severity on the specific duration was analyzed by the conditional bivariate copula function and confidence intervals were estimated to quantify uncertainties. The methodology was applied to Seoul station with the historical dataset (1909~2015). It was observed that the past droughts considered as extreme hydrological even ts had from 10 to 50 years of return period. On the other hand, the current on-going drought event started from 2013 showed the signif icantly higher return period. It is expected that the result of this study may be utilized as the reliable criteria based on the concep t of return period for the drought contingency plan.Keywords: Bivariate Frequency Analysis, Copula Function, Drought Event, Return Period