中文摘要：

关于上新世阶段青藏高原北部是否存在显著隆升事件这一问题目前依然存在较大的争议。本研究尝试利用沙尘气候模拟方法对上新世高原隆升的可能性做一评估。北太平洋风尘记录显示亚洲内陆干旱化在三到四百万年存在非常显著的增强，这可能是由于全球气候变冷和／或青藏高原隆升引起的。基于此，我们利用一个耦合了沙尘模块的气候模式，通过一系列敏感性试验测试大气沙尘沉积通量对于上新世以来主要气候强迫，包括冰盖变化，海表温度，大气二氧化碳浓度和青藏高原北部地形的响应。可能引起粉尘通量变化的大气环流和沙尘源区面积两个因素的改变在试验中都被考虑。模拟结果表明，冰盖扩张、海表温度下降和大气二氧化碳浓度下降这些全球变冷因素仅能解释中上新世和末次盛冰期北太地区粉尘沉积通量改变量的约三分之二，而剩下的三分之一需要归因于青藏高原北部的隆升。高原北部的隆升可以显著恶化内陆干旱状况从而提升大气粉尘浓度，支持了上新世高原北部存在明显隆升事件这一观点。

英文摘要：

Different opinions have been derived from geological evidence on whether there was significant tectonic uplift in the northern Tibetan Plateau （NTP） during the Pliocene. We made the first attempt in this paper to explore the possibility of the Pliocene uplift by climate modeling. Previous studies on eolian sediment records show that the inland Asian aridity was largely intensified 4-3 million years ago, which was proposed to be induced by global cooling and/or the Tibetan uplift. Employing a coupled climate-dust model, we conducted a series of experiments in order to test the sensitivity of atmospheric dust deposition fluxes to different forcings including the ice sheets, sea surface temperature, atmospheric CO2 concentration and the NTP topographic height. Both changes in atmospheric circulations and dust source areas are considered. The results show that, global cooling induced by all the above-mentioned factors except the NTP uplift can only explain approximately 2/3 of the increase in the dust deposition fluxes in the downwind North Pacific from mid-Pliocene to the last glacial maximum and the remaining 1/3 of the increase can be attributed to NTP uplift. The NTP uplift has remarkably strengthened the inland aridity and raised the dust levels, suggesting that considerable tectonic uplift events should have occurred in the NTP during Pliocene.