Understanding the sensitivity of hourly precipitation extremes to the warming climate over Eastern China

Theoretically, under the warming climate, due to the increase of the atmospheric water vapor, the precipitation extremes would increase. The Clausius-Clapeyron (CC) scaling indicates an increase of precipitation extremes at a rate of about 7% globally. However, the response of precipitation extremes to global warming is complex globally. In this study, we investigated the hourly precipitation extremes-dew-point temperature scaling relation in eastern China and the theoretical explanation. It is shown here that the hourly precipitation extreme intensity increases with the dew-point temperature (DPT), following the CC scaling rate. Conversely, as DPT exceeds similar to 22 degrees C, the negative scaling exists, particularly for the southern part of China. The change in the scaling direction as the DPT exceeds 22 degrees C may be attributed to the negative scaling of precipitation efficiency/vertical velocity with DPT. The increase in the convective inhibition and decrease in the temperature advection above similar to 22 degrees C, partially explain the negative scaling of precipitation efficiency and vertical velocity with DPT. Our results may help understanding the variations in precipitation extremes under future warming.

Automated summary

The study in eastern China reveals that hourly precipitation extremes intensity increases with dew-point temperature, following a specific scaling rate. However, a negative scaling phenomenon occurs when the dew-point temperature exceeds 22 degrees Celsius, especially in southern China.