1981~2010 年达坂城浅层地温变化特征及气候响应

Shallow Geothermal Change Characteristics and Response to Climate Change of Dabancheng in 1981-2010

本文利用气候倾向率法分析了达坂城地面及各浅层地温的变化趋势特征。结果表明:各浅层地温均呈升高趋势,地面 0 cm 温度的气候倾向率最大,为 0.779℃/10a,由浅至深依次减小,5 cm、10 cm、15 cm、20 cm地温的气候倾向率分别为 0.648℃/10a、0.630℃/10a、0.564℃/10a、0.527℃/10a;夏季各层地温升温趋势最为明显,倾向率达 0.807℃/10a,其次为春季和秋季分别为 0.770℃/10a 和 0.687℃/10a。突变分析表明各浅层地温均在 1997 年发生了突变增加。利用偏相关分析法分析了达坂城地区地温变化的原因,结果表明:平均气温、日照时数与地温呈正相关,降水量、平均风速与地温呈负相关。气温升高和风速显著减小,对地温的正效应很可能超过了降水增加、日照时数减少对地温的负效应,因此使地温明显升高。

The climate tendency rate method was used to analyze the tendency of the shallow geothermal changes of Dabancheng. The results showed that the shallow ground temperature increased gradually. The ground temperature of 0 cm has the largest climate tendency rate of 0.779?C/10a, which decreases from shallow to deep in turn. 5 cm, 10 cm, 15 cm, 20 cm ground temperature climate tendency rate is 0.648?C/10a, 0.630?C/10a, 0.564?C/10a, 0.527?C/10a respectively. The warming trend of each layer is most obvious in summer with the tendency rate reaching 0.807?C/10a, which is followed by spring and autumn with the rate of 0.770?C/10a and 0.687?C/10a respectively. Mutation analysis showed that the shallow ground temperature was mutated to increase in 1997. Partial correlation analysis method was used to analyze of the reason why the ground temperature of Dabancheng increased. The results showed that average temperature and sunshine duration were positively correlated with ground temperature, and precipitation and rage wind velocity were negatively correlated with temperature. The positive impact of air temperature increase and wind speed decrease on the ground temperature is likely to exceed the negative impact of increase in rainfall and reduction in sunshine time on the geothermal, so temperature increased significantly.