Rapid reorganization of monsoon seasonality during the 2.8 ka event

Seasonal hydroclimate variability governs water availability, agricultural productivity, and societal resilience across monsoon Asia, yet its response to abrupt climatic extremes remains poorly constrained. Here we present seasonal-resolution δ18O and trace-element data from an annually laminated stalagmite in northern China, providing a direct reconstruction of East Asian summer monsoon (EASM) seasonality across the 2.8 ka extreme event. The records reveal rapid (