Jeongeun Won

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4.1. Effect of Zero Precipitation Events on Minimum Time-Scales As flush droughts become more frequent, the need for short-term drought assessments is increasing. However, the monthly SPI currently in use has difficulty responding to such flush droughts. There is a need for a method to accurately capture droughts that develop rapidly in a short period of time. As part of this, the need to apply a daily time-scale SPI is increasing. Yoo et al.

1. Introduction Currently, most river runoff predictions are based on hydrological models that require extensive parameter adjustments based on historical runoff records. This includes explicitly addressing the spatial variability of processes, boundary conditions, and watershed physical properties [1]. Progress in this field is driven primarily by advances in computer technology and the availability of observational data with high spatiotemporal resolution [2].