| Title |
Development of Drought Index based on Streamflow for Monitoring Hydrological Drought |
| Authors |
유지영(Yoo, Jiyoung) ; 김태웅(Kim, Tae-Woong) ; 김정엽(Kim, Jeong-Yup) ; 문장원(Moon, Jang-Won) |
| DOI |
https://doi.org/10.12652/Ksce.2017.37.4.0669 |
| Keywords |
가뭄지수;갈수예보;기준유량;변동시점;ROC 곡선 분석 Drought Index;Low-flow;Standard Flow;Change-Point;ROC Curve Analysis |
| Abstract |
This study evaluated the consistency of the standard flow to forecast low-flow based on various drought indices. The data used in this study were streamflow data at the Gurye2 station located in the Seomjin River and the Angang station located in the Hyeongsan River, as well as rainfall data of nearby weather stations (Namwon and Pohang). Using streamflow data, the streamflow accumulation drought index (SADI) was developed in this study to represent the hydrological drought condition. For SADI calculations, the threshold of drought was determined by a Change-Point analysis of the flow pattern and a reduction factor was estimated based on the kernel density function. Standardized runoff index (SRI) and standardized precipitation index (SPI) were also calculated to compared with the SADI. SRI and SPI were calculated for the 30-, 90-, 180-, and 270-day period and then an ROC curve analysis was performed to determine the appropriate time-period which has the highest consistency with the standard flow. The result of ROC curve analysis indicated that for the Seomjin River-Gurye2 station SADI_C3, SRI30, SADI_C1, SADI_C2, and SPI90 were confirmed in oder of having high consistency with standard flow under the attention stage and for the Hyeongsan River-Angang station, SADI_C3, SADI_C1, SPI270, SRI30, and SADI_C2 have order of high consistency with standard flow under the attention stage. |