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A stalagmite-based isotope record (No. H82) from Nanjing Hulu Cave, spanning from 16.5 to 10.3 ka BP, provided strong evidence for a coherence relation between the East Asian summer monsoon (EASM) and the North Atlantic climates on millennial time scales. Here we extend the high-resolution δ 18 O time series back to 22.1 ka BP with additional 7 230 Th dates and 573 stable isotope measurements on the lower part of that sample. The new record with a decadal resolution, piecing together with the previous data, provides a detailed, complete Last Glacial Maximum (LGM)/deglacial history of the EASM. Two centennial-scale weak monsoon events are detected within the analogue H1 event, and can be correlated to corresponding Greenland temperature shifts. This suggests a rapid re-organization of atmospheric and oceanic circulations during the ice-rafted debris (IRD) event in North Atlantic. A strengthened EASM event spanning from 19.9 to 17.1 ka BP, firstly reported here, reaches on average a half of the monsoon intensity of Bølling warming with its peak close to the full level. Taking all available evidence from continental and oceanic sediments into consideration, we suggest that a forcing mechanism behind the event would be a positive feedback of the tropical Pacific Super-ENSO cycles in response to precessional changes in solar irradiation.Nanjing Hulu Cave, stalagmite, East Asian summer monsoon event Millennial climatic variability (Heinrich and DO) during the Last Glaciation, firstly identified in the Greenland ice cores [1] , was then world-widely found in various geological archives (e.g. deep sea sediments [2] and stalagmite records [3] ). A well-dated Chinese cave record indicated a positive relation between the EASM and the Greenland temperature on millennial time scales [3] . Furthermore, the coupling relationship between Super-ENSO in the tropical ocean-atmosphere system and high-north -latitude temperature was supported by Pacific planktonic foraminifera records [4] . These studies may validate a common forcing mechanism underlying the Northern Hemisphere millennial climate variability. As early found by Heinrich [5] and then confirmed later by an algae record from equatorial North Atlantic [6] , frequency of millennial scale climatic variability (including the IRD events) is in accord with half a precessional periodicity. This suggested that a nonlinear orbital forcing may play a key role in the millennial climatic variability. Indeed, model results [7] and sediment records from the Arabian Sea and the South China Sea [8, 9] suggested that the precessional forcing is the primary pacer modulating the Indian and Pacific hydrological cycles and monsoons on orbital time scales. However, relation between the millennial climatic variability in the tropics and the precessional forcing has not been revealed yet. It is generally accepted that the LGM (23-19 ka BP [10] or 22-19 ka BP [11] ) was the coldest period due to the

One stalagmite oxygen isotope record from Sanbao Cave, China, established with 7 230 Th ages and 355 oxygen isotope data, provides a continuous history of the East Asian Monsoon (EAM) intensity for the period from 284 to 240 thousand years before present (ka BP) with typical errors of 3 4 ka. This new record extends the previously published stalagmite 18 O record back to the marine oxygen isotope stage (MIS) 8. The MIS8 EAM record broadly follows orbitally-induced insolation variations and is punctuated by at least 6 strong-and 3 weak-monsoon events. The weak monsoon events around Termination III (TIII) are dated at ~257 ka BP, ~253 ka BP and ~246 ka BP, and can be distinctly correlated to three ice-rafted debris (IRD) events in the North Atlantic. The TIII appears to display a two-phase glacial termination process, similar to that of the TI and TII. Phase I is characterized by a weak monsoon stage of several millennia (~250 ~244 ka BP) that is coeval with the full atmospheric CO 2 concentration and Antarctic temperature rise. Phase II is marked by a rapidly intensified monsoon at ~244 ka BP, accompanied by the rapid increase in CH 4 concentration and maxima of Antarctic temperature and atmospheric CO 2 concentration. Our observation supports the Milankovitch theory that the Northern Hemisphere (NH) summer insolation triggered the glacial-interglacial cycles. In addition, our results suggest that the Southern Hemisphere (SH) warming may have facilitated the termination of the AM at the TIII.We previously reported high-resolution Asian Monsoon records over the past 224000 years from Sanbao, Hulu, and Dongge caves, China, and provided insights into the factors that control the strength of the EAM on orbital and millennial timescales [1][2][3][4][5]. At present, our knowledge about the variability of the EAM for the antepenultimate glacial periods merely comes from the marine sediments and Chinese loess deposits [6,7]. The Chinese stalagmite records may help provide better understanding of orbital and millennial scale variability of the EAM over this period because of their dating and resolution much better than other paleo-archives. For example, the structure and timing of the TI and TII are evident in the cave records [2][3][4][5], supporting the idea that terminations are key periods for understanding mechanisms of rapid climate changes [8]. However, it is not well known whether the Younger Drays (YD)-type event existed over the TIII. A planktonic foraminiferal 18 O record from southwest Pacific marine core [9] reveals an old Antarctic Cold Reversal event (OACR) during TIII, consistent with the Vostok argon record [10]. This OACR event lasted for about 2000 years according to a chronology based on the high-resolution methane record from Antarctic ice

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