Fig. 2: Variations in brGDGTs parameters compared with the parameters of other records.

a The pH calibration based on 5- and 6-methyl branched glycerol dialkyl glycerol tetraethers (brGDGTs, dark blue solid line, this study) and mean annual average temperature (MAT) calibration based on 5- and 6-methyl brGDGTs (dark red solid line, this study). b The mean grain size (mm) (MGS, blue solid line, this study) and magnetic susceptibility (orange solid line, this study). c The mean annual average precipitation (MAPc) values reconstructed by the brGDGT-MAP model (Weinan, dark green solid line, this study). d The MAP values reconstructed by ¹⁰Be (Baoji, purple solid line). e The variations in Sanbao δ¹⁸O (the dark blue solid line indicates the results of the five-point average). f The changes in the MBT’ (dark red solid line), representing the soil water content (SWC) variations³⁶. g The changes in sea level (blue solid line)⁵⁷. h The solar radiation at 65°N (black solid line)⁴². i The benthic foraminifera-derived δ ¹⁸O stack (dark blue solid line)⁴¹. The orange and yellow bars represent the loess–paleosol cycles in the Weinan profile. The gray shading bars represent the interglacial periods in the Weinan profile, and the light-yellow bars highlight the decoupled periods between the ¹⁰Be reconstructions and our results.