【摘要】 选取青藏高速公路沿线4个典型区段,采用数值预测方法,预测4种气候变暖情景下未来50年多年冻土的退化特征。结果表明:初始多年冻土地温越低,对气候变暖的敏感性越弱;随着初始多年冻土地温的升高,多年冻土对气候变化的主要响应方式由年平均地温升高向上限下降、下限抬升转变。A2情景下冻土退化最严重,线性情景和B1情景多年冻土退化较为温和。到2064年时,A2情景下安多冻土厚度减薄7.94 m,风火山年平均地温升高1.34℃。未来青藏高原低温多年冻土向高温多年冻土转变,冻土厚度减薄,活动层厚度增加,在线位选择和结构设计中应引起充分的重视。更多还原

【Abstract】 Four typical sections along Qinghai-Tibet Expressway are selected to predict the degradation characteristics of permafrost in the next 50 years under four climate warming scenarios by numerical prediction method.The results show thatthe lower the initial permafrost temperature is, the weaker the sensitivity to climate warming is.And with the increase of initial permafrost temperature, the main response mode of permafrost to climate warming changed from increase of mean annual ground temperature(MAGT) to descent of permafrost table and ascent of permafrost base.Permafrost degradation is the most serious under A2 scenario, while permafrost degradation is mild under linear scenario and B1 scenario. By 2064, under A2 scenario, the thickness of Anduo permafrost was reduced by 7.94 m, and the annual average ground temperature of Fenghuo volcano was increased by 1.34 C.In the future, the low-temperature permafrost of the Qinghai-Tibet Plateau will change to high-temperature permafrost. The thickness of the permafrost will decrease and the thickness of the active layer will increase, which should be paid more attention to in site selection and structural design.更多还原