A Study on the Appropriateness of the Drought Index Estimation Method Using Damage Data from Gyeongsangnamdo, South Korea

Youngseok Song,Moojong Park

doi:10.3390/atmos12080998

Abstract

Drought is one of the disasters that causes the most extensive and severe damage. Therefore, drought prevention must be performed for administrative districts at the national level rather than the individual level. This study proposes a drought index estimation method for Gyeongsangnamdo, South Korea that evaluates its appropriateness through a comparison with damage data over several years. The standardized precipitation index (SPI) by duration was used as the drought index that was estimated for 13 rainfall stations located inside and outside Gyeonsangnam-do using the Thiessen method and cluster analysis. The SPI of Gyeongsangnamdo by duration based on the Thiessen method and cluster analysis for the years when drought damage occurred was compared with an SPI value of −2.0, which is the extreme drought condition, to determine its appropriateness. For the evaluation of the appropriateness, the performance indicators of the mean absolute deviation (MAD), mean squared error (MSE), and root mean square error (RMSE) were used. The analysis results showed that SPI by duration based on the cluster analysis method was more appropriate for damage data over many years than that based on the Thiessen method.

Highlights

Drought is a natural disaster characterized by the lack of precipitation for a protracted period, resulting in water shortage that greatly affects a wide range of socioeconomic sectors including agriculture, living, and industry
Various drought indices have been developed for drought evaluation, including the standardized precipitation index (SPI), standardized precipitation evapotranspiration index (SPEI), reconnaissance drought index (RDI), Palmer drought severity index (PDSI), and effective drought index (EDI) [4–8]
The results show that cluster analysis exhibited higher accuracy than the Thiessen method, indicating that the cluster analysis method has higher precision in estimating SPI by duration for drought damage

Summary

Introduction

Drought is a natural disaster characterized by the lack of precipitation (i.e., rain, snow, or sleet) for a protracted period (i.e., more than 3 to 12 months), resulting in water shortage that greatly affects a wide range of socioeconomic sectors including agriculture, living, and industry. The acceleration of climate change leads to changes in the intensity, spatial extent, frequency, duration, and timing of weather and climate extremes that worsens drought conditions, which vary in frequency, duration, and severity per climatic zone, experienced across vast portions of the world [1–3]. Korea has faced continuous severe droughts, which is normally concentrated in spring and autumn, and experiences varying drought damages depending on regional characteristics. Various drought indices have been developed for drought evaluation, including the standardized precipitation index (SPI), standardized precipitation evapotranspiration index (SPEI), reconnaissance drought index (RDI), Palmer drought severity index (PDSI), and effective drought index (EDI) [4–8]. SPI can evaluate drought using only precipitation, is less complex to calculate, and is more comparable across regions with different climates.

Methods

Results

Discussion

Conclusion