Abstract: Hourly station rain gauge data over South China during 1966-2005 were used to analyze the corresponding relation between precipitation extremes and surface air temperature in the warm season (May to October). The results show that both daily and hourly precipitation extremes in South China increase with temperature rise, and more extreme events show an earlier transition to the two-times Clausius-Clapeyron (CC) relationship. Meanwhile, daily as well as hourly precipitation extremes, present a decrease after the peak point around 25℃, and the decrease of daily precipitation extremes appears to be much more intense. In view of rainfall durations, hourly precipitation extremes are presented by short duration and long duration precipitations individual. Results show that the dramatic decrease of hourly rainfall intensities around 25℃ is mainly caused by short duration precipitation, and long duration precipitation extremes seldom occur when surface air temperature breaks 28℃.

Key words: precipitation extremes, surface air temperature, rainfall duration, Clausius-Clapeyron relation