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Profound archaeological transformations that mark the collapse of Neolithic Cultures around Central China during the late third millennium BC have been identified widely. However, the causes for their collapse have been disputed. In this paper, paleoclimatic data are synthesized to show that an interval of severe climatic anomalies occurred across much of China, which were synchronous with a climatic event identified at least in the Northern Hemisphere. Our syntheses also indicate that this climatic interval was not only one of several climatic events during the Holocene, but marked the middle Holocene climatic transition (the ending of Holocene optimum). Based on geological evidences and analysis of relationships between variations in the intensity of the East Asian monsoon and changes in distributional pattern of monsoon-related rain belts in eastern China, we suggest that this climatic anomaly was superimposed on the middle Holocene transition and significantly altered the hydrological regime. This generated an environmental framework of drought in the north and flooding in the south of China, which was mainly responsible for the collapse of Neolithic Cultures around the Central Plain.

Magnetic Susceptibility measurements were conducted at 10 cm intervals in the Baoji section, a 160 m thick loess deposit in the southern Loess Plateau. An independent time scale was developed under control of paleomagnetic data by assuming that the eolian dust deposition rate during glacial periods is 1.5 times higher than that during interglacial periods. The 1600 susceptibility results were then plotted to the time scale which has a basal age of 2.5 Ma based on paleomagnetic measurements. Fourier analysis of the susceptibility time series shows strong spectral peaks centered at about 400,000, 100,000, 40,000 and 20,000 years, coinciding with the Milankovitch periods of paleoclimate. The dominant climatic periodicity recorded in the loess section appears as a function of the time interval considered: the 0–0.8 Ma interval is dominated by the period of about 100,000 years, the 0.8–1.6 Ma interval by 40,000 year cycles and the 1.6–2.5 Ma interval also by 100,000 year rhythms.

Deserts and the Loess Plateau in North China constitute an environmental coupling system which has undergone periodic changes in the Quaternary period, attributable mainly to the variations of the global surface energy system. Thirty-seven loess-paleosol formations of the last 2.5 Ma have been identified in the Loess Plateau, representing thirty-seven cycles of climate from cold to warm and of wind intensity from strong to weak. In historical literature, more ‘loess falling’ events in relatively cold-dry periods have been recorded, than in comparatively warm-humid periods. Loess is being currently deposited. Analyses on three contemporary ‘dust storm’ events show that the scope, mass fluxes, and manners of loess deposition are controlled by different atmospheric circulation systems.