南北过渡带地区浅层地温的全球变化响应——以信阳城区为例

利用中国南北过渡带中部河南省信阳城区1961-2017年逐月平均气温和逐月0～20 cm浅层地温资料,采用统计学、Mann-Kendall和功率谱分析等方法分析了过去57 a信阳城区浅层地温的变化特征及其对全球变化的响应.结果表明:(1) 1961年以来信阳各层年平均地温均呈显著升高趋势;(2) 1961-2017年信阳各层年、季平均地温周期多以2～4 a为主,且秋季和冬季周期现象明显;(3) Mann-Kendall分析显示,5～20 cm地层年均地温于20世纪90年代初发生突变,而0 cm地温却于20世纪末发生由冷转暖的转折;(4)信阳浅层地温对气温变化极为敏感,0 cm地表温度对气候变化的响应最为敏感.

Response of Shallow Ground Temperature in the North-South Transition Zone under Global Warming: A Case Study of Xinyang City

Based on the monthly mean surface air temperature and shallow ground temperature data at the depth of0 ～ 20 cm from 1961 to 2017 in Xinyang City,located in central North and South Transition Zone,the temporal characteristics of shallow ground temperature and its response to climate change were analyzed by using the statistical,MannKendall test and power spectral analysis methods. The main conclusions were as follows:(1) During the past 57 years,the annual mean shallow ground temperature for each layer showed a significantly warming trend.(2) Significant periodicity of 2 ～ 4 a was detected in annual and seasonal mean ground temperature over the past 57 years,and the quasi-cycles were obvious especially in the autumn and winter seasons.(3) During the early 1990 s,there the existed significant abrupt changes in Xinyang ground temperature of 5 cm,10 cm and 20 cm. However,the ground temperature of 0 cm turned from cold to warm conditions during the late 1990 s.(4) The shallow ground temperature was significantly correlated with the surface air temperature in Xinyang. The most sensitive layer to climate change was the surface layer.