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The Chinese loess–paleosol succession, deep-sea sedimentary sequences and ice cores are the three types of paleoclimatic records. Measurements were made of the ancient climatic proxies of magnetic susceptibility, median diameter of grain size and content >40 μm, and the CaCO3 content of samples collected at 1 cm depth intervals in the fourth paleosol layer of the Luochuan loess-paleosol section on the Chinese Loess Plateau. Wavelet analysis of the data identified cycles of climate change, which were compared to the marine δ18O record of SPECMAP. The results showed that: (1) when the fourth paleosol layer was forming, the paleoclimate was relatively stable but five extreme climatic events were identifiable as occurring around 408, 381, 376, 368 and 361 kaBP; (2) two of these regional events differed from the global trend; (3) during marine isotope stage (MIS)11, the fourth paleosol layer of the Luochuan loess section recorded a regional quasi-19 ka climatic sub-cycle and (4) this sub-cycle was also reflected globally in the SPECMAP data indicating that, during MIS11, this sub-cycle was regionally and globally synchronized.

Summary. Quantitative information on the soil erosion periods of Pleistocene on the Loess Plateau is rare. Here, we present results of the field work at Luochuan, Weinan, Tongchuan, Fufeng, Baoji, and Yangling, and a comparison between the SPECMAP, ODP-677 δ 18 O curve, and the magnetic susceptibility curve of loess-paleosol sequence. We took the conformity surfaces between the loess and paleosol layers as credible erosion surfaces. After some field work and analyses on the erosion surfaces, we concluded that intensive soil erosion had occurred during the climate transform period, especially when the climate changed from cool-dry to warm-wet. After comparing the SPECMAP, ODP-677 δ 18 O curve, and the magnetic susceptibility curve of the loess, the simultaneous leaps of these curves might show climate transition periods and also erosion events that could occur. This comparison suggested that there might be 13 erosion periods, which existed at 2.580 MaBP, 2.190 MaBP, 1.870 MaBP, 1.240 MaBP, 1.120 MaBP, 0.964 MaBP, 0.865 MaBP, 0.760/0.780 MaBP, 0.621 ~ 0.479 MaBP, 0.412 MaBP, 0.336 MaBP, 0.245 MaBP, and 0.128 MaBP. Among these erosion periods, nine of them were identified by the erosion surfaces; four of them had more than two sites. Especially, the erosion happened at ~ 0.128 MaBP was identified by more than ten erosion surfaces, this erosion period had laid a foundation for the modern landform of the central south Loess Plateau.