河南信阳市近62年来极端气温变化特征及周期分析

通过对河南省信阳市每日气温资料的搜集和整理，运用线性拟合及累积距平、Morlet复数小波等方法对WMO发布的10种极端气温指数进行了计算和分析。研究了信阳地区近62年来极端气温变化特征及周期性。结果表明，近62年来信阳地区的极端最高气温几乎没有变化，极端最低气温在波动变化中有小幅上升趋势，夏日、热夜、暖夜天数呈现波动上升，冰日、霜日、冷夜、冷日天数呈下降趋势。极端最高气温、极端最低气温、冷夜、暖夜、冷日、暖日都存在35 a左右的周期。夏日、冰日、热夜、霜日存在37 a左右周期。冰日的变化存在着5个左右的周期，极端最低气温、冷日与冷夜的变化存在4个左右的周期。其中极端最低气温、霜日、冰日、冷夜、冷日、暖夜都有5 a以下的周期。冷夜和暖夜、冷日和暖日、夏日和冰日以及热夜和霜夜存在负相关的关系，其中冷夜和暖夜以及热夜和霜日的变化幅度较大，它们之间有负相关关系。冷日和暖日以及夏日和冰日的变化较小，负相关的关系不太明显。总体来说，近60年来，信阳地区极端天气热指数呈上升趋势，极端天气冷指数呈下降趋势，整体气温呈现上升的趋势，其中近二十年气温上升更明显。

Characteristics and periodicity of extreme temperature in recent 62 years in Xinyang, Henan Province

Based on the daily temperatures data in Xinyang, Henan Province, 10 kinds of extreme temperature indices published by WMO were calculated and analyzed using linear regression and accumulated anomaly, morlet complex wavelet and other methods. The results show that in recent 62 years in Xinyang, extreme maximum temperature almost has no change and extreme minimum temperature has a rising trend; while summer, hot night, warm night have fluctuated rise; days of ice, frost, cold night, cold day are declined. Extreme maximum temperature and extreme minimum temperature, cold night, hot night, cold day, warm day have cycles of 35 years. Summer, ice day, hot nights, frost have cycles of 37 years. Ice day variation have cycles of 5 years. Extreme minimum temperature, cold night cold day variation have cycles of 4 years. Cold night and warm night, cold day and warm day, summer and ice day, hot night and frost night have negative correlation. On the whole, in nearly 60 years, extreme weather hot index is on the rise, extreme cold weather index is on the decline. The overall temperature has a rising trend, and temperature rises more obviously during recent two decades.