近52年卫辉浅层地温的变化特征分析

利用1961～2012年卫辉市0～20 cm各层逐月平均地温,采用气候倾向率、累积距平、信噪比等气候统计方法,研究了近52年卫辉市浅层平均地温的变化趋势、气候突变和异常年份等。结果表明,近52年卫辉市年平均浅层地温除地面外均呈现极显著的升高趋势,升幅为0.07～0.18℃/10a,15 cm升温率最大;四季浅层地温中,冬、春季呈现极显著的升高趋势,尤其是15～20 cm,升幅为0.17～0.34℃/10a,夏、秋季升高趋势不显著。浅层地温冬季、春季和年平均分别在1976、1986年和20世纪90年代前期发生了突变,夏、秋季无突变;年平均地温异常偏高多发生在20世纪90年代,异常偏低多发生在20世纪60年代和21世纪。气温升高及降水减少是影响地温上升的主要原因。

Analysis on Variation Characteristics of Shallow Ground Temperature in Weihui in Recent 52 Years

Using monthly average ground temperature of 0-20 cm layer in Weihui City during 1961-2012, adopting climate tendency rate, accu- mulative anomaly, noise-signal ratio, the variation trend of shallow ground temperature, abrupt climate change and abnormal year of Weihui City in recent 52 years were studied. The results showed that annual average shallow ground temperature indicate extremely significant rising trend ex- cept for the surface, increasing 0.07-0.18 ℃/10a, maximum in 15 era. Winter and spring showed extremely significant rising trend, especially in 15-20 cm, increasing 0. 17 -0.34 ℃/10a, the rising trend of summer and autumn is not obvious. The abrupt change of shallow ground tempera- ture in winter and spring and annual average is in 1976, 1986, early period of 1990＇ s respectively. Abnormal high annual average ground temper- ature are mostly occurred in 1990s＇ , abnormal low in 1960s＇ and 21st century. Temperature rising and precipitation reducing are main reasons for ground temperature rising.