위성기반 가뭄지수의 상호비교를 통한 한반도 농업가뭄 분석

Drought is one of the natural disasters that slowly begin to accumulate over a long period. Although there are many kinds of drought indices, one single universally accepted definition does not currently exist, which makes it difficult to evaluate drought severity comprehensively and objectively. This paper describes the comparisons of satellite-based drought indices such as SPI (Standardized Precipitation Index), NDDI (Normalized Difference Drought Index), NMDI (Normalized Multi-band Drought Index), VHI (Vegetation Health Index) and SDCI (Scaled Drought Condition Index) to analyze agricultural drought in Korea. Through an experiment using the five drought indices, we found that VHI and the SPI2 calculated from 2-month accumulated precipitation were highly correlated and appropriate to express agricultural drought in South and North Korea. Also, the SPI2 and VHI showed close relationships with hydro-meteorological factors and vegetation production variables. For future work, it is necessary to develop a comprehensive drought index which can cover various aspects of drought including precipitation, evapotranspiration, soil moisture, and vegetation state.