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Qunf Cave oxygen isotope (δ18Oc) record from southern Oman is one of the most significant of few Holocene Indian summer monsoon cave records. However, the interpretation of the Qunf δ18Oc remains in dispute. Here we provide a multi-proxy record from Qunf Cave and climate model simulations to reconstruct the Holocene local and regional hydroclimate changes. The results indicate that besides the Indian summer monsoon, the North African summer monsoon also contributes water vapor to southern Oman during the early to middle Holocene. In principle, Qunf δ18Oc values reflect integrated oxygen-isotope fractionations over a broad moisture transport swath from moisture sources to the cave site, rather than local precipitation amount alone, and thus the Qunf δ18Oc record characterizes primary changes in the Afro-Asian monsoon regime across the Holocene. In contrast, local climate proxies appear to suggest an overall slightly increased or unchanged wetness over the Holocene at the cave site. Southern Oman speleothem oxygen isotope and multi-proxy data reveal diverse changes in the Afro-Indian summer monsoon circulations and local hydroclimate conditions during the Holocene, confirming climate model simulations. [ABSTRACT FROM AUTHOR]

The 8.2 ka event has been extensively studied, whereas its structure is ambiguous in North China. Here we present a high‐resolution (∼1 year) δ18O record from annual laminated speleothem from Beijing to characterize the detailed variability across this event in North China. Our record indicates a dry 8.2 ka event spanning 8.254–8.107 ka BP with a two‐stage structure superimposed by three prominent high δ18O excursions. The identical structure of speleothem δ18O records between North and central China during the event suggests a common forcing/response in East China, whereas the progressively increased offset between their average values may reflect changes in moisture source or rainout effect. A close comparison with the Greenland ice core records suggests a strong linear response of the Asian summer monsoon to the North Atlantic climate changes across the early and middle stages of the event, but a different mechanism in the termination processes. Plain Language Summary: As the most pronounced abrupt climate event in the Holocene, the 8.2 ka event has been studied using various geological archives worldwide, but its detailed structure in North China and its link to other climate systems remain poorly understood. Since the Beijing speleothem δ18O, a proxy of the precipitation δ18O, is sensitive to the Asian summer monsoon (ASM) variations, it allows us to establish precise timing and structure of the 8.2 ka event and estimate the cause of it. Our new speleothem δ18O record from Beijing reveals a two‐stage structure superimposed by three "V‐shape" excursions during the event and almost exactly covaries with another published speleothem record from central China, suggesting coherent climate changes over the east ASM domain in response to the same forcing. The gradually increased offset between them probably results from the changed atmospheric circulations. Our results suggest a fast climatic signal propagation from the North Atlantic to the ASM domain during the early and middle 8.2 ka event, and another forcing mechanism in the termination processes. Key Points: Annual laminated speleothem δ18O record from North China manifests a two‐stage 8.2 ka event superimposed by three positive excursionsHigh consistency in speleothem records from North and central China on interdecadal to multidecadal timescales indicates a common driverThe climate forcing for the termination process is different from the early and middle stages of the 8.2 ka event [ABSTRACT FROM AUTHOR]

High-resolution and precisely dated hydroclimate records in the southeastern Tibetan Plateau (TP) remain sparse beyond the Holocene, which hampers our ability to understand the hydroclimate variability in this important Indian summer monsoon (ISM) fringe area and its global teleconnection. Here we present 3-y resolution δ18O and δ13C records from a laminated stalagmite (RG-3) from Rige Cave in the southeastern TP, spanning the Younger Dryas (YD). The records allow us to precisely characterize the timing, structure, and particularly centennial-scale events within the YD, and probe the control factors of precipitation δ18O (δ18O p) in the ISM fringe area. On centennial–millennial timescales, the Rige δ18O record shows coherent pattern with the East Asian summer monsoon (EASM) counterpart, combined with modeled δ18O p results and spatial analysis, suggesting that δ18O p in this part of the TP is largely controlled by the large-scale atmosphere circulation (or the ISM strength), and the altitude increase in the TP may not potentially result in an opposite δ18O p pattern at least in the monsoonal TP regime. We also found significant δ13C-δ18O covariation on the centennial timescale, suggesting a coincided ISM rainfall and biomass change during the YD. In the Rige records, one weak centennial-scale ISM event (namely the intra-Allerød cold period, IACP) and three strong centennial-scale ISM events within the YD (namely A1′-A2′-A3′) were prominent and occurred between ∼12,470 and 12,310 ± 14, ∼12,210–12,090 ± 12 and ∼12,010–11,920 ± 12 y BP (before present, where present = 1950 CE), respectively. Spectral analyses of Rige records also revealed a significant ∼200-y periodicity, which is nearly in-phase with observed centennial-scale variations of the North Atlantic temperature and mid-latitude westerly-jet during that time. These observations support the hypothesis that the solar de Vries cycle (207-y) triggered the centennial-scale climate variations in high northern latitude, leading to the ISM variations via fast atmospheric processes. • Precipitation δ18O and its millennial-centennial patterns in SE Tibet Plateau are controlled by large monsoon circulations • Centennial δ13C-δ18O covariations in Younger Dryas suggest a link of the local biomass to Indian summer monsoon rainfall • Centennial Indian summer monsoon events in Younger Dryas correlate precisely to the North Atlantic climate variations • Solar de Vries cycle (207-y) triggered centennial Indian summer monsoon variations via North Atlantic climate changes [ABSTRACT FROM AUTHOR]

Although the 8.2 ka event is a well-known globally documented abrupt climate event, its detailed expression in tropical southeastern Africa is poorly constrained. Here we present a high resolution and precisely dated record of the regional hydroclimatic variability between 8.5–7.5 ka BP from a polymorphic speleothem (ABC-1) from northwestern Madagascar. In combination with the exclusive recurrences of calcite layers (indicative of wetter conditions), the distinctly negative excursions in the ABC-1 δ18O record manifest a wet 8.2 ka event that spanned from 8.230 to 8.053 ka BP. The event is characterized by the replacement of shorter-term (interannual to interdecadal) δ18O-δ13C coherence with the longer-term (multidecadal to centennial) coherence, suggesting a stable and well-developed forest system during the 8.2 ka event. Our data reveal a two-stage structure of the 8.2 ka event, which is superimposed with two brief pluvial episodes in each stage. The widely documented two peaks/troughs during Stage-I suggest rapid propagation of climate signal through atmospheric processes triggered initially by the freshwater forcing, whereas the divergent behaviors of the peaks/troughs in Stage-II in different climate systems may suggest a different forcing. • Exclusively episodic deposition of the calcite layers and lower speleothem δ18O manifest a wet 8.2 ka event in NW Madagascar. • The 8.2 ka event in NW Madagascar exhibits a two-stage structure with each stage superimposed by two severe pluvial episodes. • The timescale variation of coherence between δ18O and δ13C indicates the resilience of the ecosystem to climate change. [ABSTRACT FROM AUTHOR]