The idea that uplift of Himalaya and Tibet caused onset and enhancement of Asian Monsoon is not new, but it has never been tested because the knowledge on the timing and mode of onset and evolution of the Asian Monsoon as well as those of Himalaya and Tibet uplift has not been sufficient. Situation changed recently due to the drastic progress in reconstruction of Asian Monsoon evolution through intensive studies of loess in China as well as of hemipelagic sediments of the Japan Sea. The knowledge on the timing and process of Himalaya-Tibet uplift has also been accumulated. In addition, climate model, which is necessary to examine the linkage between Himalaya-Tibet uplift and monsoon onset and evolution, has improved drastically.
In this synthesis, I summarized recent advances in our knowledge on the onset, evolution, and variability of Asian Monsoon, and reconstructed probable process of its evolution based on compilation of the paleoclimate data. Then, I compared individual reconstructed steps of the Asian Monsoon evolution with individual stages of Asian Monsoon simulated for every step of Himalaya-Tibet uplift by climate models, so as to specify the degree of Himalaya-Tibet uplift that best explains the Asian Monsoon evolution. The history of Himalaya-Tibet uplift reconstructed in this way is compared with current knowledge on the tectonic history of Himalaya-Tibet uplift.
Paleoclimatic reconstruction suggests that desertification in inland Asia and onset of Asian Monsoon started approximately at 22 Ma, and evolved stepwise approximately at 8 Ma and 4 Ma. Such stepwise evolution of Asian Monsoon seem to correspond to uplift stage of 40, 60, and 80% of present height of Himalaya and Tibet according to climatic model simulation by Abe et al. (2003). These estimates are basically conformable with the current knowledge on uplift history of Himalaya and Tibet.
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