Abstract:
The consequences of global climate change in the next one hundred years is a hotly-debated topic at present, and the deep discussion of the driving mechanism for global climate change can truly help recognize the global climate change. The continuous growth of Tibetan Plateau has absorbed a huge amount of atmospheric CO
2, which leads to the sharp drop of the atmospheric CO
2 concentration. From the greenhouse climate, the Earth has entered into an icehouse climate characterized by the cycling of glacial and interglacial periods, and has become a new carbon reservoir. During the interglacial period, the Tibetan Plateau and the Mongolian Plateau transported a huge amount of fresh water to the inland areas at middle and low latitudes (referred as the inland area below), which resulted in the strong chemical weathering of silicate rocks. The vegetation and lacustrine deposition were developed, which absorbed huge amount of atmospheric CO
2, as a carbon sink. During the glacial period, the Tibetan Plateau and the Mongolian Plateau eventually transported a large amount of surface fresh water and dust from the inland areas to the high latitude areas, resulting in the occurrence of desertification in the inland areas. The absorbed CO
2 was far less than the emitted amount, and the inland areas became the carbon source area. Therefore, the atmospheric CO
2 concentration increased. This mechanism has maintained the low concentration and pseudo dynamic equilibrium of atmospheric CO
2 since the Miocene. The mean surface temperature drove the circulation of fresh water between high and low latitudes. The huge amount of anthropogenic carbon emission caused the rapid rise of atmospheric CO
2 concentration and global warming. Therefore, the fresh water returned to the inland area, resulting in the rapid green in inland areas and more intense chemical weathering of silicate. The ability to absorb atmospheric CO
2 was dramatically enhanced, and the inland areas were switched from the carbon source area to the carbon sink area, which prevented the further rise of atmospheric CO
2 concentration. According to the preliminary calculation in this study, when atmospheric CO
2 concentration reaches (510±40)×10
-6, the rapid increasing trend will be restrained, as early as 2050 and as late as 2090. Future century-scale climate change is therefore predictable and periodic, driven by tectonic activities within the Earth and Sun.