珠峰地区浅层地温的变化特征-以定日县为例

基于西藏定日气象站1980-2019年逐月平均气温、0~20cm浅层地温资料,应用气候统计方法,分析了近40a定日浅层地温的变化特征。结果表明:40年来,定日各层(除5cm外)年平均地温均呈升温趋势,升温幅度为0.03~0.187℃/10a,0cm升温率最大,15cm升温率最小,5cm地温呈不明显的下降趋势,春、冬季各层地温升温最显著,除了0cm层外各层地温夏、秋季呈降温趋势;各层(除5cm外)年平均地温从2000s后均陆续发生突变现象,各层地温突变时间点不一致,但均是从相对偏冷期跃变为相对偏暖期,0cm和20cm在2000s前后明显发生了由冷变暖的转折;定日年平均气温升温率比各层地温都大,通过了0.01水平的显著性检验,其距平变化趋势和时段与各层地温相似,年平均气温与20cm层地温的相关性最显著;5cm地温与其他层次变化规律存在明显的差异。

Varation Characteristics of Shallow Geotemperature in Mt.Qomolangma Region by Taking Tingri County as an Example

Based on the monthly mean air temperature, 0~20cm shallow ground temperature data at the weather station in Tingri from 1980 to 2019, with climatic statistical methods, the changing characteristics of shallow ground temperature in Tingri County were analyzed. The results showed that the annual average ground temperature of all layers (except 5cm) in Tingri in the past 40 years showed a warming trend, and the warming range was 0.03~0.187℃/10a, the warming rate of 0cm was the largest, the warming rate of 15cm was the smallest, the ground temperature of 5cm showed an insignificant decreasing trend, the warming of all layers was the most significant in spring and winter, and the ground temperature of each layer except the 0 cm layer showed a cooling trend in summer and autumn. The annual mean ground temperature of each layer (except 5cm) had a sudden change since 2000s, and the sudden change point was not consistent in each layer, but the sudden change point was from relatively cold period to relatively warm period, on the layers of 0cm and 20cm had an obvious change from cold to warm before and after 2000s. The annual mean temperature warming rate of Tingri was larger than that of all layers and passed the 0.01 significance test. The trend and period of changing were similar to those of each layer, and the correlation between the annual mean temperature and temperature in the 20cm layer was the most significant. Ground temperature in the 5cm layer was significantly different from other layers.