全球变暖背景下囊谦地区近57年季节性冻土的变化特征及气候影响因子分析

Analysis of the Changing Characteristics and Climate Impact Factors of Seasonal Permafrost in the Past 57 Years in Nangqian Region under the Background of Global Warming

利用青海省囊谦国家基准气象站1960—2017年冻土、气温、地表温度资料,运用气候倾向率、Mann-Kendall非参数趋势检验等统计方法分析了囊谦季节性冻土的变化特征。结果表明:囊谦最大冻土深度近58年来以-2.69 cm/10年的倾向率减少,1991年出现了1次由大变小的突变,1992年后以极显著的趋势在减小,消融日21世纪初比20世纪提前了1个月。年代际变化特征为,20世纪60~70年代最大冻结深度处于相对减小期,70年代初至90年代初以极显著趋势在增大,90年至21世纪初以极显著趋势在减少。

Using the frozen soil,temperature,and surface temperature data from the National Standard Meteorological Station of Baoqian,Qinghai Province from 1960 to 2017,the seasonal changes in frozen soil in Baoqian were analyzed using statistical methods such as climate tendency rate and Mann Kendall non parametric trend test.The results show that the maximum frozen soil depth in Baoqian has been decreasing at a trend rate of-2.69 cm/10 a in the past 58 years.In 1991,there was a sudden change from large to small,and after 1992,it decreased significantly.The melting date in the early 21 st century was one month earlier than that in the 20 th century.The characteristics of interdecadal changes are that the maximum freezing depth was in a relatively decreasing period from the 1960 s to the 1970 s,increased significantly from the early 1970 s to the early 1990 s,and decreased significantly from the 1990 s to the early 21st century.