표준유역 면적강수량 특성 분석을 통한 한반도 물관리 정책 지원 가능성 검토

Abstract

Based on observation data from the Korea Meteorological Administration (1973~ 2024), this study calculated daily areal precipitation for standard watersheds across the Korean Peninsula using the Thiessen polygon method. The Rainfall Persistence Index (RPI), the spatial Coefficient of Variation (CV), and rainfall frequency derived from the Generalized Extreme Value (GEV) distribution were analyzed. The annual average precipitation increased from 1,191 mm in the early 1970s to 1,368 mm in the early 2000s, then slightly decreased to 1,266 mm in recent years. The spatial CV peaked in the early 2000s, indicating the highest regional disparity. Events of 10.0 mm/day exhibited an average RPI of 1.4, suggesting frequent occurrences of small- to moderate-scale rainfall persisting over consecutive days. Meanwhile, events of 50.0 mm/day showed a strong correlation with annual total precipitation (r = 0.94), highlighting their critical influence on water availability. Since 2013, GEV-based analysis has indicated that 100-year return rainfall in some watersheds has exceeded 800 mm, signaling intensifying extreme events. These findings suggest that the frequency, persistence, and spatial distribution of medium- to large-scale rainfall events should be actively considered in nationalscale water resource planning and disaster risk management strategies.