中新世以来青藏高原北部隆升及亚洲内陆沙漠形成对区域气候与环境变化影响的数值模拟研究

Based on the geological evidence that the northern Tibetan Plateau (NTP) had an uplift of a finite magnitude since the Miocene and the major Asian inland deserts formed in the early Pliocene, we will mainly use a high-resolution regional climate model to explore the effects of the NTP uplift and the related aridification of inland Asia on regional climate and environment changes in this proposal. By numerical simulations with high and low terrain in the NTP, we will analyze the regional patterns of season-dependent atmospheric circulation including the corresponding prevailing wind and their relationships with the topographic reliefs to reveal the uplift-induced temporal-spatial changes in precipitation. By numerical experiments with removal of major deserts including the Taklimakan Desert in the inland Asia, we will explore the impacts of the uplift-related desert formation in the early Pliocene on the regional aridification and increased dust cycle. Meanwhile, by sensitivity experiments with a global climate model and comprehensive comparisons between our modeling results and collected geological climate proxy records, the project will further evaluate the relative contribution and additive effect of regional factors (such as tectonic and surface characteristics) and global factors (such as land-sea distribution, Antarctic and the Arctic ice cover and atmospheric CO2 content) to deepen the understanding of the tectonic-scale evolution mechanism of climate change in central Asia since the Miocene.

基于中新世以来青藏高原北部具有有限幅度的地形隆升、上新世初塔克拉玛干等亚洲内陆沙漠形成的地质事实，重点利用一个高分辨率区域气候模式模拟研究中新世以来青藏高原北部隆升及亚洲内陆主要沙漠形成对区域气候与环境变化的影响。通过模拟分析青藏高原北部不同山地高（低）地形条件下大气环流及相应的盛行风与地形分布的关系及其随季节的改变，揭示地形隆升引起的降水变化、季节性和空间差异。通过去除亚洲内陆主要沙漠的数值试验，探讨与高原北部隆升密切相关的上新世初期内陆沙漠形成对区域气候变化及粉尘循环的影响。同时，还将利用全球气候模式的模拟试验及“模式-记录”交叉检验和综合集成研究，评估区域性构造和地表特征变化与全球性因子对亚洲中部气候变迁的相对贡献和叠加作用，阐明青藏高原北部山地隆升及亚洲内陆主要沙漠形成对中新世以来区域气候变迁的作用，深化对构造尺度上亚洲中部气候环境长期演化机制的理解。

基于中新世以来青藏高原北部地形隆升、塔克拉玛干等亚洲内陆沙漠形成的地质事实，本项研究利用高分辨率区域气候模式及全球气候模式模拟研究了高原隆升及内陆沙尘循环对区域气候环境的影响。利用海-气耦合模式完成了新生代5个特征时期的古气候模拟，揭示了大陆漂移、青藏高原区域隆升和大气CO2含量变化对新生代亚-非-澳洲季风区和干旱区起源和演化的影响及其物理机制；利用高分辨率区域气候模式完成了青藏高原北部的帕米尔高原、天山、阿尔泰山-蒙古高原和祁连山等不同山脉隆升对亚洲内陆降水变化和沙尘循环影响的系列数值试验和综合分析研究；利用包含沙尘循环的气候模式，开展了大量模拟试验，探讨了亚洲内陆的沙尘气溶胶对辐射强迫、东亚夏季风、内陆干旱及空气质量等的影响。通过这些研究深化了我们对构造尺度上亚洲中部气候环境长期演化机制的理解。本项目共发表研究论文21篇，其中SCI论文19篇，培养博士5名、硕士1名。