青藏高原隆升对我国西南地区气候的影响--从季风角度研究

Influence of the Tibetan Plateau uplift on climate evolution in southwestern China:from the monsoon perspective

青藏高原隆升作为新生代最重要的地质事件,对亚洲乃至全球气候演化产生了深刻的影响。我国西南地区因紧邻青藏高原、地形地貌复杂,该区青藏高原隆升的气候效应至今仍存在许多需要探讨的问题。本文通过整理总结青藏高原隆升与亚洲季风各子系统形成与发展的相关性,从季风的角度分析了高原隆升对西南地区气候的影响。主要结论如下:(1)对西南地区气候起控制性作用的东亚季风、南亚季风以及高原季风的形成与青藏高原的隆升密切相关。虽然东亚夏季偏南风在约22 Ma就因海陆差异形成,但冬季风却是在约7.2 Ma因青藏高原隆升才出现;南亚夏季风(西南季风)约在12 Ma因喜马拉雅山脉及临近山脉形成而出现,而其冬季风形成时间及原因与东亚冬季风相似,同样离不开青藏高原的隆升;高原季风形成的直接因素就是高原隆升,其约在36 Ma青藏高原主体隆升至约1500 m时才开始形成。(2)亚洲季风各子系统对西南地区的气候演变有重要影响。尽管东亚冬季风不能直接影响西南地区,但青藏高原隆升增强了海陆差异及其热源作用,在一定程度上扩大了东亚夏季风的影响范围,并给西南地区带来水汽;南亚冬季风使得西南地区变得相对寒冷干燥,而南亚夏季风因青藏高原的隆升得到进一步加强,其通过形成南北向的水汽通道成为西南地区温暖湿润气候的主导者;高原冬、夏季风随着青藏高原隆升使得西南地区季节性干冷与湿润气候的差异更加显著。

Background,aim,and scope As one of the most important geological events in Cenozoic era,the uplift of Tibetan Plateau had profound influences on the Asian and global climate evolution.The southwestern China is close to Tibetan Plateau and the uplift of the plateau has great impact on its climate.But so far,there are still a lot of issues that need to be investigated further.Materials and methods To study the influence of Tibetan Plateau uplift on Asian monsoon environment,and to summarize the correlation between different forms of tectonic uplifts and Asian monsoon,and especially to analyze the influence of Tibetan Plateau uplift on the climate evolution in southwestern China,this paper reviewed most of the relevant literatures in the past decades.Results The results showed that:(1)The formation of East Asian monsoon,South Asian monsoon and plateau monsoon,which control the climate evolution in southwestern China,is closely related to the uplift of Tibetan Plateau.(2)The three Asian monsoon subsystems have great impact on the climate evolution in southwestern China.Discussion(1)Although the East Asian summer monsoon formed at about 22 Ma due to sea and land differences,the winter monsoon formed at 7.2 Ma due to Tibetan Plateau uplift.Moreover,the South Asian summer monsoon formed at about 12 Ma due to the uplifts of the Himalayas and adjacent mountains,and its winter monsoon formed at the same time of East Asian winter monsoon.Remarkable facts are that the formation of plateau monsoon is directly due to plateau uplift.(2)The uplift of Tibetan Plateau has enhanced the land-sea difference,and its heat source effect expand the influence of East Asian summer monsoon and bring water vapor to southwestern China.The South Asian winter monsoon makes the southwestern region relatively cold and dry,and the summer monsoon further strengthened due to the Tibetan Plateau uplift,which has made the climate become more warm and humid by forming north-south water vapor channel.As for the winter and summer plateau monsoons,the plateau uplift has made the difference between seasonal dry-cold and humid climates in southwestern China even more significant.Conclusions The uplift of Tibetan Plateau has great impact on the climate evolution in southwestern China by affecting Asian monsoon in this region.Recommendations and perspectives The explanation of Tibetan Plateau uplift’s impact on the climate evolution in southwestern China remains controversial.Thus,it is necessary to provide more accurate data for further verification.