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第四纪研究 2011
MULTI-SCALE ANALYSIS OF EAST ASIAN WINTER MONSOON EVOLUTION AND ASIAN INLAND DRYING FORCE
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Abstract:
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 1MaB.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.