Elevation of the Gangdese Mountains and Their Simulated Impacts on Asian Climate during the Late Cretaceous

The Tibetan Plateau has a significant impact on the Asian climate due to its high topography. However, its uplift history, especially the uplift of the Gangdese Mountains in its early stage, is under intense debate. Most quantitative reconstructions are done for the Cenozoic only, impeding our understanding of the geodynamic and paleoenvironmental evolution during the Cretaceous. How high would the Gangdese Mountains be then, and what effects would they have on Asian climate? In order to explore these two questions, here we model the impacts of the Gangdese Mountains on the Asian climate during the Late Cretaceous by employing the Community Earth System Model version 1.2.2. It is found that the extent of dry land in East Asia is sensitive to the altitude of the Gangdese Mountains; it expands eastwards and southwards with the rise of the mountain range, which is due to the fact that the Gangdese Mountains can significantly reduce the precipitation over the low- to mid-latitude Asia. We then attempt to constrain their paleoaltitude using the available climate indicators in the sediments. The aridity index is further calculated for this region, and its comparison with the climate records suggests that Gangdese Mountains should be higher than 1 km but lower than 3 km during the Late Cretaceous, most likely ~2 km.