近50年来河南最高最低气温的非对称性变化特征

利用河南50个气象站点1959-2008年50a的气温资料,分析了河南区域年最高、最低气温及日较差的时空变化特征。结果表明：①1959-2008年河南区域年平均最高、最低气温在时间变化上为非对称性增长,年平均最低气温变化倾向率为0.237℃/10a;年平均最高气温变化倾向率为0.053℃/10a,前者增温幅度约为后者的4.5倍。②年平均最高、最低气温变化速度在空间分布上多数地区也呈不对称现象,最低气温在河南西北部和东南部的周口、漯河部分地区升温快,最高气温在西部的洛阳地区升温较快,而其它地区相对较慢,最终使气温日较差在东部和西北部减小幅度较大。③年平均最高气温在20世纪80年代最低,本世纪以来的8a最高;年平均最低气温在60、70和80年代均较低,本世纪以来的8a最高;年平均气温日较差在60年代最大,本世纪以来的8a最小。④年平均最高气温没有明显突变点,年平均最低气温在1997年发生突变,年平均气温日较差分别在1974年和1980年前后发生了突变。最高、最低气温变化速度不同以及突变点不一致,最终导致了气温日较差在突变点上的不一致。

Asymmetrical Change of Maximum, Minimum Temperature in Last 50 Years in Henan

The spatial and temporal change of maximum and minimum temperature and diurnal temperature range were analyzed based on the temperature data of 50 meteorological stations in Henan province from 1959 to 2008.The results showed that annual average maximum and minimum temperature increased non-symmetrically,the minimum temperature changed at the rate of 0.237℃/10y,and the maximum temperature changed at the rate of 0.053℃/10y.Annual average maximum and minimum temperature also changed asymmetric in majority area.The minimum temperature increased quickly in Northwest Henan and the maximum increased quickly in Central Henan,which resulted to diurnal temperature range reducing obviously in the east and northwest of Henan province.The Lowest annual average maximum temperature was in 1980s and the highest was in last 8 years,annual average minimum temperature kept low in 1960s,1970s,and 1980s,and the highest was in last 8 years.The highest diurnal temperature range was in 1960s,and the lowest was in last 8 years.Annual average minimum temperature changed abruptly in 1997,and no abrupt change in annual average maximum temperature.Annual average diurnal temperature range changed abruptly in 1974 and 1980.