Figure 4
Seasonal cooling events in the Chinese Loess Plateau and their comparison with other records from the Chinese Loess Plateau (a–d), high northern latitudes (e–h) and global factors (i,j) during Marine Isotope Stages (MIS) 12–10. (a,b) Magnetic susceptibility (MS) record, seasonal cooling events (red) (L4-1, S4-1, S4-2, L5-1 and S5/L5-1, from top to bottom), as documented by egg-abundance peaks, and linear accumulation rate (blue) from the Huining section, respectively. The units of loess (L5 and L4) and paleosol (entire S4, and parts of S5 and S3) are labeled on the low-field MS record. (c) Calcite content in the Luochuan section14. (d) The content of coarse grain size (> 32 μm) (blue) and frequency-dependent MS (red) in the Luochuan section5. (e) Benthic δ18O record from Ocean Drilling Program (ODP) Site 983 located at 60.4° N, 23.64° W16. The red and blue dashed lines indicate the 4.2‰ and 3.5‰ thresholds of benthic δ18O values, respectively. (f) Ice-rafted debris (IRD) record from ODP Site 980 at 55° N, 15° W in the subpolar North Atlantic17. (g) Summer sea surface temperature (SST) record from Deep Sea Drilling Project (DSDP) Site 607 at 40° N, 32.97° W18. (h) Relative abundance of the ostracod Acetabulastoma arcticum which indicates sea ice cover in the Arctic Ocean20. (i) CO2 record from the European Program for Ice Coring in Antarctica (EPICA) Dome C ice core19. (j) Spring (red) and mean annual (blue) insolation at Huining located at the latitude of ~ 36º N21. MIS is labeled on the right.
