1960~2014年河南极端气温事件时空演变分析

基于河南1960~2014年18个气象台站逐日最高温、最低温、平均气温实测数据,采用线性趋势、相关分析等方法,根据选取的16个极端气温指数,分析了河南省极端气温变化趋势和空间差异,探讨了极端气温指数的影响因素以及与该区气候变化的关系。结果表明：① 河南近55 a来日最高气温的极小值、最低气温的极大/小值、暖昼/夜日数、夏季日数、热夜日数、暖持续日数、生物生长季呈现增大/加趋势;日最高气温的极大值、冷昼/夜日数、冰/霜冻日数、冷持续日数和气温日较差呈现减小/少趋势。② 极端最低气温的变暖主要发生在黄淮海平原区、豫西南南阳盆地以及豫南桐柏山-大别山山地丘陵区;而极端最高气温的变暖则主要发生在豫西山地丘陵区。③ 与中国其他地区相比,河南极端气温近55 a的变化速率较慢,低温出现的日数显著减少;但近20 a来大部分极端气温指数的变化速率均提高了2倍多,表明该区极端气温进入了加速变化阶段。④ 相关分析表明河南极端气温指数变化可以指示该区气候变化,且地形条件是该区极端气温空间变化的控制因素。

Temporal and Spatial Variation of Extreme Temperature Events in Henan Province During 1960-2014

Based on the daily temperature (average, maximum and minimum) data of 18 meteorological stations from 1960 to 2014 in Henan province, the variation trends and spatial differences of 16 extreme temperature indices are analyzed by using the linear regression and correlation analysis methods. Besides, the influence factors of the extreme temperature indices and the relationship between extreme temperature indices and climate change are also discussed. The results are as follows: 1) In the last 55 years, coldest day (TXn), warmest night (TNx), coldest night (TNn), warm days (TX90P), warm nights (TN90P), summer days (SU25), tropical nights (TR20), warm spell duration days (WSDI) and growing season length (GSL) indicate statistically significant increasing trends. Whereas, warmest day (TXx), cool days (TX10P), cool nights (TN10P), ice days (ID0), frost days (FD0), cold spell duration days (CSDI) and diurnal temperature range (DTR) have significantly decreasing trends. 2) In terms of spatial variations, the extreme cold temperature increase in the Huang-Huai-Hai Plain, Nanyang Basin and the hilly area of Tongbai-Dabie mountainous area. Meanwhile, the increase of extreme warm temperature has mainly occurred in the western mountainous and hilly region of Henan Province. 3) Compared to other areas of China, the change rate of extreme temperature in Henan is slowly, in last 55 a, the cold days have significantly decreased. However, the change rate of extreme temperature of last 20 a has increased more than two times than last 55 a, this shows that the change rate of extreme temperature in Henan is accelerating. 4) Based on the correlation results, the variation of extreme temperature in Henan could indicate the climate change in this area. Besides, the topographic condition is the dominant factor for the spatial variations of the extreme temperature in Henan.