汶川地震前后温江不同土层温度的变化特征

运用地面气象测报业务软件,结合铂电阻地温传感器分别采集地震前后4年(2004~2012年)的土层温度,探讨汶川Ms 8.0级地震前后温江不同土层温度的变化特征。结果表明,随着土层的加深,土壤温度呈下降的趋势,且在0 cm时达最高;0、10、15、20 cm土层的5月份平均温度随着年份的增加,其温度总体上表现出先增加后降低的趋势,在2007年5月时达最高值;而40、80、320 cm土层的5月份平均温度的年际变化相对较小。浅层(0~40 cm)地温的变化幅度较大,而深层地温(80~320 cm)的变化幅度较小;其原因主要是由于浅层地温受地面天气现象的影响较大,而深层地温则受此影响较小,但其地温总体上呈逐渐增加的趋势,与太阳辐射的增强有关,且基本不受地震释放的热量影响。地震对不同土层的温度均有不同程度的影响,且随土层的加深,其影响逐渐降低,在0、5、10、15、20 cm的土层温度中,其作用尤为明显。地震对不同土层温度的影响集中体现在震后1~3 d,而震前无明显的变化,这也是当前地震预警预报较低的原因之一。

Characteristics of the Temperature in Different Depth Soil of Wenjiang before and after Wenchuan Earthquake

Abstract Using operational software for surface meteorological observation （OSSMO） and platinum resistance temperature sensor, the soil tem- perature before and after the earthquake from 2004 to 2012 were collected, the characteristics of the temperature in different depth soil of Wen- jiang before and after the Wenehuan Ms 8.0 earthquake were investigated. The results showed that soil temperature decreased when the soil layer increased, and reached the highest at the 0 cm soil layer. The average temperature of O, t0, 15,20 cm of soil layer in May increased from 2004 to 2007, and reached the highest. After that, the average temperature decreased from 2007 to 2012. However, the interannual variation charac- teristics of the average temperature of 40, 80, 320 cm of soil layer in May are relatively small. The change range of the shallow ground （0 to 40 cm） temperature is larger, while the deeper ground （80 to 320 cm） temperature are small. The reason is mainly due to the shallow ground tem- perature is strongly influenced by the ground weather phenomenon, while the deep ground temperature is affected by this small. Moreover, the ground temperature generally increased gradually, associated with the increase of solar radiation, however it is not affected by earthquake off heat. The influence of earthquake to the soil temperature is dependent on the soil layer. The impaction is decreased with the soil layer increased. However, the effect on soil temperature is particularly obvious at 0, 5, 10, 15, 20 cm. The influence of earthquake on different soil temperature is concentrated reflection after one to three days of the quake, while no obviously change before the earthquake. Therefore, it is part of the reason why the early warning forecast of current earthquake is very low.