青藏高原新近纪重大气候事件演化序列

摘要

综合分析青藏高原新近纪古气候研究的不同替代性指标,建立了高原新近纪重大气候事件的演变序列,探讨青藏高原隆升和全球重大气候事件的关系.青藏高原新近纪不同构造-地层区重大气候事件发生的时间与高原隆升事件基本吻合,说明高原隆升是青藏高原气候变化的主要因素,与全球气候变化事件既存在一致性,又存在差异性.早—中中新世青藏高原气候变化频繁,气候变冷期开始的年代早于全球约15Ma以来的降温期,说明早—中中新世高原隆升对全球变冷的贡献较大.晚中新世以来的气候事件与全球重要气候事件相吻合,说明青藏高原可能在晚中新世已经隆升到了一定高度,其对全球气候变化的影响较之前有所减弱.青藏高原气候变化除受到高原隆升影响外,亦受到全球气候变化的影响.%Through a comprehensive analysis of different indexes of the Neogene climatic studies in the Tibetan Plateau, the authors established the Neogene sequence of the major climatic events and discussed the relationship between the Tibetan Plateau uplift and the major global climate events. The fact that the time of the major climatic events in the Neogene was almost synchronous with the time of the uplift of the Tibetan Plateau means that the uplift of the Tibetan Plateau was the main factor responsible for the climate change in the Tibetan Plateau. However, there exist some temporal differences and similarities between the major climatic events in the Tibetan Plateau and the major global climate events. In the early and middle Miocene, climate change in the Tibetan Plateau was frequent, and the beginning of cooling was earlier than 15Ma, which suggests that the uplift of the Tibetan Plateau made a considerable contribution to the cooling of the Earth before the late Miocene. Since the late Miocene, major climate events in the Tibetan Plateau coincided with important global climate events, which may imply that the Tibetan Plateau had reached a certain height and its impact on global climate was weakened than before.