Abstract
Recent studies have argued that the extreme precipitation intensities are increased in almost every region across the globe due to atmospheric warming. This argument is based on the principle of Clausius-Clapeyron relationship which states that atmosphere can hold more moisture under warmer climate (~7%/°C). In our study, we have investigated the dependence of extreme precipitation intensity on temperature over Japan by using multimodel ensemble downscaling experiments of three RCMs (NHRCM, NRAMS, WRF) forced by JRA25, as well as three GCMs (CCSM4, MIROC5, MRI-CGCM3). Extreme precipitation intensity increases with temperatures up to 22°C in future climate scenarios, while the peak is 20°C for the current climate. Extreme precipitations at higher percentiles are projected to have larger rates of increase in future climate scenarios (3-5%/°C in current and 4-6%/°C in future). An insufficient water vapor supply for saturation at higher temperatures can lead to a decrease in cloud formation and extreme precipitation.
