논문 상세보기
pp.53-71
A statistical forecast model for early spring (March and April) precipitation over South Korea is developed by using multiple linear regression method. Predictors are selected among the forty five large-scale atmospheric and oceanic indices. Because the model is meant to use for real-time forecast, the predictors are chosen from the indices that have statistically significant lag correlation with observed early spring precipitation. The selected predictors of early spring precipitation are North Pacific Pattern with 6-month lead, Siberian High Index with 5-month lead and Indian Ocean Basin Mode Index with 3-month lead from March, and they are statistically independent. We applied leave-two-out cross validation. According to the regression map between these indices and synoptic circulations around Korean peninsula, these indices represent the induction of early spring rainfall by controlling East Asian jet and low level moisture flux. The regression coefficients for each training period show that three indices affects evenly at every forecast year and they show stable variability, indicating that the influence of each index does not depend on training period. The developed statistical model significantly predicted early spring precipitation over South Korea (r=0.63, p-value<0.01). Also it marks 61% of hit rate according to the three-category deterministic forecast.
