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Abstract: The Asian summer monsoon and the westerly winds interact in the mid-latitude regions of East Asia, so that climate change there is influenced by the combined effect of the two climate systems. The Holocene millennial-scale Asian summer monsoon change shows the out-of-phase relationship with the moisture evolution in arid Central Asia. Although much research has been devoted to the long-term climate change, little work has been done on the mechanism. Summer precipitation, in the marginal regions of the Asian monsoon, is strongly affected by the monsoon and the westerly winds. The purpose of this paper is to examine the mechanism of the millennial-scale out-of-phase relationship by modern summer precipitation analysis in the northwest margin of the Asian monsoon (95–110°E, 35–45°N). First, the method of Empirical Orthogonal Function (EOF) analysis was carried out to the 1960–2008 summer rainfall data from 64 stations in that region; then the water vapor transportation and geopotential height field data were studied, in order to explain and understand the factors that influence the summer precipitation; lastly, the East Asian Summer Monsoon Index (EASMI), South Asian Summer Monsoon Index (SASMI), Summer Westerly Winds Index (SWI) were compared with the EOF time series. The results indicate the complicated interannual-scale interaction between the Asian summer monsoon and the westerly winds, which can result in the modern out-of-phase relationship in the study area. This study demonstrates that the interaction between the two climate systems can be considered as a factor for the millennial-scale out-of-phase relationship. [Copyright &y& Elsevier]

• Provides a timely overview on theoretical and methodological advances in loess study. • Encloses evolution and surface processes of loess landform and deposition environment. • Investigates impacts of fault activities and geohazards in loess areas of China. Loess is a type of Quaternary sediments of the wind origin in arid and semi-arid regions. This type of sediment is widely and thickly distributed in China, forming the Loess Plateau, which is the largest bulk accumulation of loess on the Earth. The Loess Plateau of China has received great attention from scientific communities, including geologists, geophysicists and engineers worldwide. Accordingly, a wealth of investigations has been undertaken on various problems arising in this area. However, some scientific questions remain relevant and unresolved. These questions mainly present in the areas of evolution and surface processes of loess landform, depositional environments of loess sediments, impacts due to Neotectonics and fault activities in loess areas, and natural and man-made geohazards. In recent years, extensive innovative studies have been carried out to further understand the above-mentioned topics. Substantial new data, theories and insights have become available. This special issue provides a timely overview on the recent case histories, theoretical advances, laboratory and field testing and state-of-art methods in the theme of loess geology and surface processes. The papers gathered in this special issue are introduced in this article. [ABSTRACT FROM AUTHOR]