Abstract This study compared the historical and future simulations of precipitation in South Korea from INM-CM4 of Coupled Model Intercomparison Project (CMIP) 5 and INM-CM5 of CMIP6 to identify their differences for the projections of corresponding scenarios by three timeframes (annual, summer and winter) and four regions (NW, NE, SW and SE). Six performance indicators were used to quantify the models' reproducibility to precipitation at 22 stations in South Korea for the historical period (1970–2005). Then, the change rates of precipitations in near and far futures (2020–2059 and 2060–2099) were calculated for two representative concentration pathway (RCP) 4.5 and 8.5 and socioeconomic shared pathway (SSP) 2–4.5 and 5–8.5. Their uncertainties were also quantified using standard deviations and interquartile ranges. As a result, CM5 clearly showed a 7.4% improvement in six performance indicators. The change rates in far future were larger but the uncertainties were smaller. But both the rates and uncertainties in NW were the largest. Also, the uncertainties in INM-CM5 were also smaller than in INM-CM4 for all timeframes and the differences between RCP4.5 and SSP2-4.5 were absolutely larger than those between RCP8.5 and SSP5-8.5.

中文翻译：

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CMIP6 INM-CM5 优于 CMIP5 INM-CM4 在韩国降水模拟方面的进展

摘要 本研究比较了耦合模型比对项目 (CMIP) 5 的 INM-CM4 和 CMIP6 的 INM-CM5 对韩国降水的历史和未来模拟，以确定它们在三个时间框架（年度、夏季和冬季）和四个地区（西北、东北、西南和东南）。六个性能指标用于量化模型对韩国 22 个站点在历史时期（1970-2005 年）降水的再现性。然后，计算了两个代表性浓度路径 (RCP) 4.5 和 8.5 和社会经济共享路径 (SSP) 2-4.5 和 5-8.5 的近期和远未来（2020-2059 和 2060-2099）降水变化率。他们的不确定性也使用标准偏差和四分位距进行量化。因此，CM5 在六个性能指标上清楚地显示了 7.4% 的改进。远期变化率较大，但不确定性较小。但西北地区的利率和不确定性都是最大的。此外，在所有时间范围内，INM-CM5 的不确定性也小于 INM-CM4，并且 RCP4.5 和 SSP2-4.5 之间的差异绝对大于 RCP8.5 和 SSP5-8.5 之间的差异。