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Distinguishing the independent contributions of tectonic denudation and climate‐driven erosion on the production and supply of clastic materials of Chinese eolian deposits is important in understanding the dynamic links between global climate changes, tectonics, and Asian dust emission. Here, multi‐proxy rock magnetic records of detrital fractions of Chinese eolian deposits since ∼6 Ma, combined with further comparison with dust accumulation rates and geochemical data, suggest that limited production and supply of clastic materials of Chinese eolian deposits were observed between 5.6 and 4.4 Ma in a warmer climate, and thereafter an increasing trend is evident during a cooler world. We propose that intense physical erosion under cooler conditions caused increasing production of fresh detrital components, exerting dominant influences on the sediment supply to Asian eolian deposits. This study provides direct evidence of dynamic coupling between intensified physical erosion and Asian dust activity under late Cenozoic global cooling. Plain Language Summary: The dust cycle is an important component of the Earth's climate system. Glacial erosion and tectonic denudation are usually regarded as two principal factors controlling the production and supply of clastic materials of Asian eolian deposits. To date, however, the dynamic coupling between intensified glacial erosion and tectonic denudation and Asian dust activity remains challenging and has rarely been reported. Multi‐proxy lithogenic magnetic records, combined with a synthesis of published dust accumulation rates and geochemical data, demonstrate that temporal variations in the production and supply of lithogenic materials of Chinese eolian deposits over the past 6 Ma appear to be closely coupled to the global temperature and climate state. Intense glacial erosion and frost‐weathering processes during late Cenozoic global cooling led to increased production and supply of fresh detrital material from the high mountains. The significant role of global cooling in the production and release of Asian dust materials is underscored. The cryospheric control on Asian dust activity challenges previously dominant views that dryland dynamics alone exerted primary influences on atmospheric dust formation. Key Points: The production and supply of clastic materials of eolian deposits were limited during 5.6–4.4 Ma and increased toward a cooler worldIntense glacial erosion and frost‐shattering processes in a cold climate caused increasing production and supply of clastic materialsA dynamic coupling exists between intensified physical erosion and Asian dust activity under late Cenozoic global cooling conditions [ABSTRACT FROM AUTHOR]

Eolian loess deposits contain valuable information about past climate changes and erosion history in dust source regions. In contrast to the extensive investigations of paleoclimatic implications of Eurasian loess, continental erosion information in the loess deposits has received less attention, particularly on the global or hemispheric scales. The present study combines citrate‐bicarbonate‐dithionite (CBD) magnetic mineral extraction procedures and linear regression of magnetic parameters to analyze Eurasian loess. We find that lithogenic susceptibility of Quaternary loess deposits in Central Asia, Europe and the Chinese Loess Plateau shows synchronous long‐term increases since ∼0.6–0.5 Ma, suggesting intensive glacial erosion and/or river incision to have occurred in the surrounding mountains of dust source regions after the mid‐Pleistocene climate Transition. The dramatic increase in lithogenic susceptibility of Eurasian loess provides new insights into the close relationships between global climate changes and dust source erosion since the late Cenozoic. Plain Language Summary: Eolian loess deposits are valuable materials for elucidating the development and mechanisms of dust activities in Eurasia and their links with global climate changes and erosion processes in mountainous areas of dust sources on tectonic and orbital time scales. Continental erosion information retrieved from the Eurasian loess, however, has rarely been reported. A comprehensive analysis of lithogenic magnetic signals in Eurasian loess through mathematical and CBD extraction approaches demonstrates that lithogenic susceptibility of Quaternary loess‐paleosol sequences in Eurasia increased significantly after ∼0.6–0.5 Ma, in coincidence with increasing global ice volume and climatic instability after the mid‐Pleistocene climate Transition (MPT). We suggest that increased ice volume and climate fluctuation amplitudes after the MPT produced vast amounts of fresh Fe‐bearing silicate particles and detrital magnetite in mountainous areas of Eurasia, which can be attributed to a dramatic intensification of glacial erosion and river incision, thereby causing the loess lithogenic susceptibility increase. The results demonstrate that variations in lithogenic magnetic properties of loess deposits can be used to reconstruct the erosional history of main mountains surrounding the dust source regions in Eurasia over geological timescales. Key Points: Lithogenic magnetic susceptibility of Quaternary loess deposits in Eurasia increased synchronously after ∼0.6–0.5 MaGlobal cooling may account for the increase in lithogenic susceptibility of Eurasian loessSpatial variations of lithogenic susceptibility of Eurasian loess are related to varying distances between the source and the sink region [ABSTRACT FROM AUTHOR]

Pronounced differences in concentration, alignment and grain-size distribution of the magnetic minerals have been identified between loess and palaeosol samples from the section at Xifeng (Central Chinese loess plateau). Superparamagnetic magnetite formed in situ plays an important role in controlling magnetic low field susceptibility. The variable brown-red colouration of the loess-palaeosol sequence is due to a significant hematite component produced by pedogenesis. The magnetic fabric of the palaeosols is weaker than that of the loesses. This is taken as evidence that the formation of ultrafine ferromagnetic minerals by pedogenesis is the most likely explanation for the observed susceptibility enhancement in palaeosols (4 to 10 times higher than in loesses). It is argued that variations of frequency dependent susceptibility are sensitive recorders of second order palaeoclimatic variations during glacial periods, whereas bulk susceptibility seems to be an appropriate measure of palaeoclimate change during interglacial periods.