资源环境科技发展态势分析平台

Precipitation extremes with devastating socioeconomic consequences within the South American Monsoon System (SAMS) are expected to become more frequent in the near future. The complexity in SAMS behaviour, however, poses severe challenges for reliable future projections. Thus, robust paleo‐monsoon records are needed to constrain the high spatiotemporal variability in the response of SAMS rainfall to different climatic drivers. This study uses Ti/Ca ratios from X‐ray fluorescence scanning of a sediment core retrieved off eastern Brazilian to trace precipitation changes over the past 322 kyr. The results indicate that despite the spatiotemporal complexity of the SAMS, insolation‐forcing is the primary pacemaker of variations in the monsoonal system. Additional modulation by atmospheric p CO₂ suggests that SAMS intensity over eastern Brazil will be suppressed by rising CO₂ emissions in the future. Lastly, our record reveals an unprecedented strong and persistent wet period during Marine Isotope Stage 6 driven by anomalously strong trade winds.