35 ka BP climate simulations in East Asia and probing the mechanisms of climate changes

摘要

Paleoclimate modeling has become an important tool to detect the future climate of the global warming that is difficult to be validated. The paleoclimate modeling has to be evaluated by regionally geological data in order to determine if it is able to reproduce a reality of climate states. Geological evidence shows that there was a warm-wet interstadial at 35000+ -3000 a BP in China, which provides an important climate period to be historical analogue for the future climate changes induced by greenhouse gas emissions. Integrated geological records of phase of the MSB from China also provide basements for evaluation of 35 ka BP climate modeling. This paper reports the paleoclimate experiments applied by various forces, validates the outputs by geological data, consequently improving the boundary conditions in the experiments and making the paleoclimates more approach the reality. The simulations show an increased temperature in the mid-low latitudes and an extended rain-belt northwards in East Asia, while a decreased temperature in high latitudes and a strong exchange of the N-S atmospheric circulation. As there is only ca. 10-15 ka from 35 ka BP to the LGM (21 ka BP) during which climate rapidly changed from a warm-wet interstadial to a typical ice age, this simulation provides scientific basis to recognize the criteria of global warming and trends of natural climate development.