围绕1998~2014年间安徽省极端降水事件,展开了不同时间尺度暖季极端降水与温度的关系研究。结果表明,从年际尺度上看,极端降水强度和极端降水频数与气温和温度日较差的相关关系呈现南负北正的反向特征,尤以北部的正相关最显著。定量结果表明,安徽省区域平均的暖季极端降水频数和极端降水量对升温的变化百分率分别为13.7%/°C和0.03%/°C。从日(小时)尺度上看,气温低于25°C时,随着气温的升高极端降水量增加,且基本遵循一倍(二倍)的Clausius-Clapeyron变率。但在气温高于25°C时,随着温度的升高,日和小时极端降水量出现不同程度的下降,尤以前者减少的最显著。进一步比较不同小时尺度极端降水与气温关系发现,随着时间尺度的增长,气温增长后极端降水量下降的关系变得尤为明显。这可能与单日内极端降水在偏高温时以短时降水为主有关。
The relation between precipitation extremes(PEs) and temperature in Anhui Province on different time scales during 1998-2014 has been investigated. On the interannual scale, the relationship between the magnitude of PEs and temperature presents a south-north dipole pattern with positive(negative) correlation over northern(southern) Anhui. Similar results are detected in the relation between the frequency of PEs and temperature. The quantitative results show that the frequency(magnitude) of PEs over Anhui decreased(enhanced) by 13.7%/°C(0.03%/°C) with the temperature change. This suggests that the frequency of PEs is more sensitive to temperature change. On the daily and hourly scales, the extreme precipitation increased with increasing temperature. Daily extreme precipitation exponentially increase with temperature at the Clausius-Clapeyron(C-C) scaling rate. A super-CC scaling rate exists for hourly extremes, with increases in extreme precipitation observed at the rate about double the CC scaling rate for temperature. More importantly, both the daily and hourly extreme precipitation are found to decrease at the higher end of local temperature variations. Furthermore, the relation between PEs and temperature has been examined at scales of different hours. With increases in the time scale, the decrease becomes more significant. This may be related with the fact that the PEs in one day may be dominated by short duration PEs at higher temperature.