西藏阿里地区气候变化及其对季节性冻土的影响

打开文本图片集

中图分类号：P467 文献标识码：A 文章编号：0488-5368（2025）10-0070-08

Abstract：Seasonal frozen soil is highly sensitive to climate change.To elucidate the efect of climate change onseasonal frozensoil intheNgari Plateau of Tibet，this study aimed to provide valuable insights forlocal engineering design，construction，and operations.Based on observational data from national meteorological stations inthe Ngari region，we analyzed climate trends，cumulativeanomalies，and the climate signal strength to assess climate change，permafrost dynamics，and the efects of climatic factors on frozen soil.The analysis revealed a significant temperature increase in the Ngari region between 1974 and 2O23，with an average anual rise of 1.1∘C ，following a notable shift in 1998.Annual precipitation decreased by 41.5mm aftera marked change in 1988.From 1993 to 2O23，annual sunshine duration declined by 229.2 hours.Theannual ground temperature exhibited a linear increase of 2.5∘C . Over the same period， the initial soil freezing date was delayed by 6 days，whilethe thawing date advanced by14.5 days.Consequently，the duration of the frozen soil period decreased linearly by23.7 days，and the maximum frozen depth decreased by 28.O cm. Air and ground temperatures were identified as the primary influencing factors.Specifically，a increase in the average October temperature delayed the initial freezing date by 2.4 days，while a 1.0∘C rise in the average March temperature advanced the thawing date by 4.4 days. Moreover，a 1.0∘C increase in the average temperature from November to March shortened the frozen period by3.4days，and asimilar rise from November to Februaryof the follwing year reduced the maximum frozen depth by 10.0cm . In conclusion，the significant rise in air and ground temperatures directly afects the onset andend of soil freezing，the duration of the frozen period，and the maximum depth of seasonal frozen soil，whereas precipitation and sunshine duration have limited impact.This study highlights the effcts of climate change inthe Ngari region，particularlythe decreasing frozen depthand shortened frozen duration，and provides a scientific basis for climate adaptation and infrastructure planning.

Key words： Climate change；Seasonal frozen soil；Mutations；Ngari prefecture of Tibet

引言

冻土按其时间的长短，可分为季节冻土和多年冻土两类[1.2]。（剩余10568字）