东亚冬季风演变和亚洲内陆干旱化信号的多尺度分析

MULTI-SCALE ANALYSIS OF EAST ASIAN WINTER MONSOON EVOLUTION AND ASIAN INLAND DRYING FORCE

对中国灵台黄土剖面1MaB.P.粒度时间序列和赵家川剖面3.6Ma风尘通量时间序列进行经验模态分解,探讨东亚冬季风和亚洲内陆干旱化的演变特征,发现:1)1MaB.P.以来,东亚冬季风波动主要周期是100ka,40ka和20ka,其中100ka的周期为主导周期;2)在100ka,40ka和20ka周期即偏心率周期、黄赤交角周期、岁差周期尺度上对比发现,东亚冬、夏季风的强弱变化并非完全对应,在不同周期上相位和振幅差别的原因不甚了解,有待进-步深入研究;3)3.6MaB.P.以来黄土高原风尘通量的波动存在明显的400ka,201ka,100ka,53ka,27ka,14ka和6.6ka周期,并以100ka,53ka和27ka为主周期,青藏高原构造隆升对亚洲内陆干旱化的发展和东亚季风演变有着重要影响。

On the glacial-interglacial cycles of the Milankovitch theory research is the mature and generally accepted astronomical theory of climate change. The classic Milankovitch astronomical theory of climate change is that the three elements of Earth＇s orbit caused by changes in the high latitudes of the Northern Hemisphere summer insolation changes in volume, causing the Earth＇s climate in the Quaternary glacial-interglacial cycles. With further study of hot spots and the difficulties encountered, the following three areas： driving force issue, cycle and phase, how to build a solid physical foundation of the model and observational data reconstruction scientific evaluation of simulation results. With its successful application to the nonlinear and nonstationary data, the new time series technique Empirical Mode Decompositon（EMD）is introduced in order to gain insight into the paleoclimate. Time series of Magnetic Susceptibility（MS） and Mean Grain Size（MGS） since 1 MaB. P. recorded in the given section of Loess Plateau which are located in Lingtai and mass accumulation rates of deposits at Zhaojiachuan are made analyses using EMD. The results showed that ： （ 1 ） The quasi-100ka,40ka and 20ka are discovered evidently, 100ka cycle fluctuations play a leading role to East Asian winter monsoon in 0 - 1MaB. P. （2）The East Asian winter and summer monsoon evolution in different periods were relatively strong and weak position, and even some stage or another both a considerable strength of growth and decline,in the 100ka,40ka and 20ka scale; （3）100ka,53ka and 27ka cycle fluctuations play a leading role to the evolution of mass accumulation rates of deposits at Zhaojiachuan. The Tibetan Plateau uplifting resulted in an increasing role in Asian monsoon and Asian inland drying evolution.