Abstract
Drought indices are expected to use for evaluation of quantitative goal of a water plan and drought severity of a drought event. However, no index can provide such comparison of different hydro-climate regions with the same scale, such as comparison between Tokyo Metropolitan area and California. From this viewpoint, we investigated the effectiveness of PDSI by applying to a drought event in the Tone River system for the purpose of comparison of quantitative goal of a water plan and drought severity of a drought event.
In addition to PDSI, deviation of storage rate and rainfall in the unit of month are applied as other indices. Considering river intake reduction rate as drought severity, we analyzed correlations between these three indices and drought severity. The results shows no correlation for any index and suggest any index are not appropriate for drought index.
