Future intensity-depth-frequency curves estimation in Korea under representative concentration pathway scenarios of Fifth assessment report using scale-invariance method

Many Global Climate Models (GCMs) or Regional Climate Models (RCMs) are being developed around the world and are being used in future climate change adaptation planning. However, in Korea, future rainfall data as a national standard scenario are provided on a daily basis, so it is difficult to apply directly to the design of hydraulic structures considering the impact of climate change. In this study, a method for estimating future intensity-depth-frequency (IDF) curves in Korea is proposed using a simple scale-invariance assumption associated with trend analysis of future extreme rainfall data. First, the scale characteristics of hourly rainfall data observed at 60 meteorological stations operated by Korea Meteorological Administration (KMA) are examined, and scale parameters of IDF curves are estimated from observed scale-invariance characteristics. Second, the future daily annual maximum rainfall data provided by KMA-RCM is bias-corrected. Various methods are used for the correction of biases of rainfall depths. The third is trend analysis, which is used to determine the mean and the coefficient of variance of future daily annual maximum rainfall time series in future years. Finally, future IDF curves are estimated by combining scale-invariance method and trend analysis.