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High-resolution stalagmite δ18O records, representing Asian summer monsoon (ASM) intensity, were reconstructed from Wulu and Xiao caves, southwestern China, over Chinese Interstadials (CIS) 25 and 22. A most prominent feature of these stalagmite records is a persistent ASM strengthening throughout the entire event, different from a gradual cooling in corresponding events at Greenland and Antarctica. It implicates that the cooling in the Southern Hemisphere may intensify the ASM circulation through increased cross-equatorial flow, which overwhelms the northern high-latitude impact. Combined with previous published records over the past two interglacial-glacial cycles, diverse trends of CIS events generally match with changes in North Hemisphere summer insolation (NHSI). Accordingly, three modes of CIS ASM variability can be observed, i.e., ASM strengthening when NHSI increases, weakening when NHSI decreases, and a relatively stable ASM during NHSI peak. We argue that NHSI variability or interhemispheric gradient could change the strength of cross-equatorial flow, and in turn, alter the landward transport of monsoonal moisture. The mean isotopic composition of moisture, inherited by stalagmite δ18O signal especially in southern China, is likely a reflection of energy balance between hemispheres. [ABSTRACT FROM AUTHOR]

A 20-year-resolution speleothem δ18O record from southern China reveals a detailed Asian summer monsoon (ASM) history between 73.6 and 62.3 ka. ASM changes during Interstadial 19 and late MIS 4 matched Greenland temperature variations but were antiphased with Antarctic temperatures. However, long-term strengthening of the ASM in early MIS 4 agrees well with the gradual Antarctic warming, when Greenland remained in a stable cold state. More specifically, the ASM was less variable during peak interstadials in contrast to striking instabilities during stadials. These observations suggest that the factors dominating ASM variability change through time. During early MIS 4, negligible freshwater perturbations occurred in the North Atlantic, and sea-surface temperatures in the low- to midlatitude Pacific Ocean reached the modern level. Thus, an expansion of the Intertropical Convergence Zone (ITCZ) was likely important for the long-term ASM rise. In late MIS 4, the antiphase correlation between ASM and Antarctic temperature could be attributed to freshwater inputs into the North Atlantic and a southerly positioned ITCZ. Consequently, meridional ITCZ shifts, although within a limited latitudinal band, would result in an antiphase relationship between interhemispheric climate changes. Otherwise, an in-phase correlation could be expected if the centroid of ITCZ is stable along the equator. [ABSTRACT FROM AUTHOR]

Stable isotopic measurements on the upper 168 cm of stalagmite DG24 from southern China, which is annually-laminated above 74.8 cm (∼11.8 ka), reconstruct a history of detailed Asian summer monsoon (ASM) variability and soil processes between 14.8 and 10.3 ka. The climate sequence of Bølling-Younger Dryas (YD)-Preboreal events is evident in δ 18 O record. In the Preboreal, four-year-resolution and annually-counted δ 18 O record reveals that the ASM strengthening can be divided into three phases, with a prominent and persistent rise initiated at about 11.2 ± 0.3 ka, likely in response to interactions between ocean, atmosphere, and ice sheets. In contrast, the long-term δ 18 O depletion is absent in the δ 13 C and annual layer records, which characterize persistent centennial oscillations and likely represent relative humidity of the soil. At multi-decadal scale, prominent ASM failures are generally consistent with periods of δ 13 C enrichment and decreased layer thickness. When compared with solar proxies, centennial-scale δ 13 C changes match well with solar activity regardless of the observed disparity between ASM and solar records, and common cycles of 130 and 300 years are identified in both the atmospheric Δ 14 C and speleothem δ 13 C records. This implicates that during the Preboreal local soil humidity budget and CO 2 production, indicated by the δ 13 C and annual layer records, is more sensitive to changes in solar output than the regional hydroclimate variability recorded by the δ 18 O signal. [ABSTRACT FROM AUTHOR]

We present two isotopic (δ 18 O and δ 13 C) sequences of a twin-stalagmite from Zhuliuping Cave, southwestern China, with 230 Th dates from 14.6 to 4.6 ka. The stalagmite δ 18 O record characterizes orbital- to decadal-scale variability of Asian summer monsoon (ASM) intensity, with the Holocene optimum period (HOP) between 9.8 and 6.8 ka BP which is reinforced by its co-varying δ 13 C data. The large multi-decadal scale amplitude of the cave δ 18 O indicates its high sensitivity to climate change. Four centennial-scale weak ASM events during the early Holocene are centered at 11.2, 10.8, 9.1 and 8.2 ka. They can be correlated to cold periods in the northern high latitudes, possibly resulting from rapid dynamics of atmospheric circulation associated with North Atlantic cooling. The 8.2 ka event has an amplitude more than two-thirds that of the Younger Dryas (YD), and is significantly stronger than other cave records in the Asia monsoon region, likely indicating a more severe dry climate condition at the cave site. At the end of the YD event, the δ 13 C record lags the δ 18 O record by 300–500 yr, suggesting a multi-centennial slow response of vegetation and soil processes to monsoon enhancement. [ABSTRACT FROM AUTHOR]

The paleoclimate application of speleothem δ 13 C is influenced by site-specific processes. Here we present four stalagmite δ 13 C records from two caves in southern China, covering early and late Marine Isotope Stage (MIS) 3 and the Holocene, to investigate the spatio-temporal pattern of calcite δ 13 C changes and the relationship with Asian monsoon (AM) variability. In each growth period, precessional- to millennial-scale changes are clear in the δ 18 O record. In contrast, millennial variability is absent in the δ 13 C record, which characterizes persistent centennial oscillations. However, centennial-scale δ 18 O variations agree well with those of δ 13 C, with a larger amplitude in δ 13 C changes (about twice that of δ 18 O). This suggests that soil humidity balance associated with regional hydrological circulations is important for these centennial δ 13 C changes, although evaporation-related kinetic fractionation can induce concurrent enrichments in δ 18 O and δ 13 C. In frequency, the detrended δ 18 O and δ 13 C records are coupled at a periodicity of about 300 yr during the last glacial period and 150 yr during the Holocene. Those centennial-scale δ 13 C variations are generally consistent with Greenland temperature variability, indicating a climate response over broad regions. Thus, strong co-variation of δ 18 O and δ 13 C records should have a climatic origin, even if it is amplified by kinetic effects. [ABSTRACT FROM AUTHOR]

Climate during the early Holocene was highly variable due to the complex interplay of external and internal forcing mechanisms. The relative importance for them on the Asian monsoon (AM) evolution yet remains to be resolved. Here we present two-to six-yr-resolution oxygen isotope (δ 18 O) records of five stalagmites, four of which are annually-laminated, from Qingtian Cave, central China, revealing detailed AM variability between 10.9 and 6.1 ka BP. Over the contemporaneous periods, the δ 18 O records agree well with each other at multi-decadal to centennial timescales. When pieced together with the previously published isotopic data from the same cave, the final δ 18 O record reveals detailed AM variability from the last deglaciation to the mid-Holocene, consistent with other cave records. The most striking feature of the δ 18 O record is the recurrence of centennial-scale oscillations, especially during the annually-counted period (8.8–6.1 ka BP). Cross-wavelet analyses between the δ 18 O record and solar proxies show strong coherence at 200-yr cycle, suggesting that solar output was actively involved as a primary contributor. The AM depression at 8.2 ka BP is indistinguishable in amplitude and pattern from a series of weak AM events after 8 ka BP. We speculate that these centennial-scale AM changes might be regulated by the positive feedbacks of oceanic/atmospheric interactions to the solar activity under the condition of the retreat of continental ice-sheets. [ABSTRACT FROM AUTHOR]

ABSTRACT A speleothem record from south-western China characterizes in detail the millennial-scale changes in Asian Monsoon (AM) intensity from 39.3 to 28.7 ka. The calcite δ18O profile, with an average resolution of ∼8 years, shows several strong monsoon events concurrent with Greenland Interstadials (GIS) 8-4. To gain a systematic perspective of AM millennial-scale variability, the new and previously reported data from the same cave are combined, showing that AM variation exhibits a broad similarity with Greenland ice δ18O records and with Antarctica but in an opposite sense. For the interval that encompasses GIS 5 and GIS 4.1, however, our stalagmite δ18O record depicts a sustained strong monsoon with no distinctive oscillation between these interstadials. Another prominent characteristic in our record is a gradual transition into Chinese Interstadial (CIS) 8, which is well constrained by an annually laminated sequence. We find that an initial rise in monsoon intensity, lasting a few centuries, significantly precedes the abrupt onset of CIS 8 in the AM realm. This suggests that atmospheric moisture and heat transport are probably capable of inducing abrupt climate change when a rapid reorganization of ocean/atmosphere circulations passes a tipping point. [ABSTRACT FROM AUTHOR]

Abstract: The regional climate correlation within the Northern Hemisphere in the cold/dry mid-Younger Dryas event (YD) remains elusive. A key to unraveling this issue is sufficient knowledge of the detailed climate variability at the low latitudes. Here we present a high-resolution (3-yr) δ18O record of an annually laminated stalagmite from central China that reveals a detailed Asian monsoon (AM) history from 13.36 to 10.99ka. The YD in this record is expressed as three phases, characterized by gradual onsets but rapid ends. During the mid-YD, the AM variability exhibited an increasing trend superimposed by three centennial oscillations, well-correlated to changes in Greenland temperatures. These warming/wetting fluctuations show a periodicity of ~200yr, generally in agreement with centennial changes in cosmogenic nuclides indicated by the 10Be flux from the Greenland ice. This relationship implies that centennial-scale climate changes during the mid-YD are probably caused by solar output and rapidly transported over broad regions through atmosphere reorganization. [Copyright &y& Elsevier]

Abstract: Although the initiation and continuation of orbital and millennial climate transitions were reported to be roughly similar, little is yet known about the extent to which their sequences of climate events are linked together in the same physical processes. Here we present a stalagmite isotope record from Wulu Cave, southwestern China, based on 1200 oxygen isotope data and 15 230Th ages, registering a detailed history of the Asian Monsoon (AM) from 61.3 to 50.5 ka BP with an average resolution of 12 yr. Two replicated, high-resolution calcite δ18O profiles show four millennial-scale strong summer monsoon events, analogous in timing and structure to Chinese Interstadials A.17–A.14 (CIS A.17–A.14), as recorded elsewhere in China and Greenland Interstadials 17–14 (GIS 17–14). These events exhibit two distinct phases, consistent with multi-decadal/centennial shifts in Greenland temperature and storminess. This relationship reveals a tight coupling between high- and low-latitude climates at sub-millennial scales, implying a role for westerly winds in linking Greenland temperature and the AM. Around the Marine Isotope Stage (MIS) 4/3 boundary, successive AM events resemble, but in higher frequency, structure of the Bølling–Younger Dryas (YD) surrounding Termination I. Along with evidence from similar shifts in bipolar temperature and atmospheric CH4, we suggest that the recurrence of similar climate structure worldwide is likely caused by changes in Atlantic meridional overturning circulation (AMOC) at various timescales under thresholds of global ice volume boundaries, as predicted by the bipolar seesaw model. [Copyright &y& Elsevier]

Changes in orbital-scale stalagmite δ18O (δ18O s) recorded from two caves in southern China reveal a clear precessional cycle during Marine Isotope Stage (MIS) 5 and from MIS 9.3 to MIS 8.3. At these sites, δ18O s values in MIS 5.5 and MIS 9 were relatively lower than MIS 5.3, 5.1 and MIS 8, and gradually increased towards MIS 5.1 and MIS 8.3, respectively. A similar pattern of variability of δ18O s can be observed in other cave records south of 30° N. This southern mode of variability of δ18O s closely mimics changes in northern summer insolation, the areal extent of continental ice sheets and atmospheric CO 2 concentrations, suggesting that the direct forcing of summer insolation on landward transport of monsoonal moisture can be further modulated by the Earth's boundary conditions. In contrast, δ18O s records around 30° N or northward register a relatively stable precessional cycle, among which δ18O s values during the precession minimum (P min) are similar. This regional disparity implies that during the P min , the strength of northward propagation of monsoonal moisture probably remained constant at northern sites. Moreover, a dampening effect may have limited 18O-depleted moisture transfer to mid- and high-latitude cave sites, especially during peak interglacials (i.e., MIS 5.5, MIS 9), which may be associated with shifts in the southern edge of the Westerly jet and the average position of the Intertropical Convergence Zone. Another possibility could be that more locally-recycled or near-sourced (isotopically-enriched) moisture contributed to precipitation changes at the northern sites. • A gradual enrichment of δ18O s values in Pmin in southern China • A stable precessional cycle in δ18O s records around 30°N and northward • Control of NHSI and Earth's boundary conditions on southern δ18O s variability • Interplay of Westerly wind and ITCZ on stalagmite δ18O records at northern sites [ABSTRACT FROM AUTHOR]

Abstract: An annual layer-counted and 230Th-dated stalagmite oxygen isotope record from Qingtian Cave in Hubei province, central China, provides an Asian Monsoon (AM) history across the Allerød to Younger Dryas (YD) transition, with an average 2.5-year resolution. Seasonal δ 18O profiles indicate that the calcite δ 18O is a sensitive proxy for AM changes, and the close similarity between the Qingtian and other cave records from eastern China suggests a large-scale regional coherence of monsoonal precipitation δ 18O variations associated with the temperature changes in high-northern latitudes. The annually-resolved chronology with a U–Th age uncertainty of less than 100 yr defines the timing, duration and transition of the early Allerød, the intra-Allerød cold period (IACP), the late Allerød, and the start of the YD. The 160-yr-long IACP, with two brief reversals, is clearly shown in both δ 18O and lamina thickness records. The early and late Allerød, separated by the IACP, are characterized by several decadal to centennial cycles of δ 18O variations, each punctuated by sub-cycles. These decadal to centennial monsoon variations correlate with the Greenland temperature changes, supporting a model simulation that the decadal North Atlantic Oscillation (NAO) and North Pacific Oscillation (NPO) are coupled via atmospheric circulation under glacial boundary conditions, perhaps affecting tropical/subtropical monsoon changes. However, the monsoon transition between the late Allerød and YD lasted 380 yr, longer than the analogous Greenland temperature shift by at least 130 yr [Stuiver, M., Grootes, P.M., GISP2 oxygen isotope ratios. Quat. Res. 53 (2000) 277–284]. This implicates other links besides the direct link between Greenland and the AM, which is now well documented. One possibility is the influence by Southern Hemisphere climate via cross-equatorial air flow [An, Z.S., The history and variability of the East Asian paleomonsoon climate. Quat. Sci. Rev. 19 (2000) 171–187]. [Copyright &y& Elsevier]

The dynamical adjustment process (DAP) is a requisite for climate system to arrange for a new equilibrium state. To evaluate the detailed structure of DAP during Heinrich Stadial (HS), high-resolution speleothem-based Asian summer monsoon (ASM) variability was reconstructed, separately covering HSs 5 to 1. In these calcite δ18O records, a gradual increase of ASM intensity is evident in each mid-HS, followed by a centennial-scale ASM stability lasting on average 590 years during late HS. At this time, δ18O values decrease by 1%, about 50% of the total HS, compared with maximum values in early HS. This structure of monsoonal HS in speleothem records is not reflected in temperature variations at the Greenland, but is well mirrored in middle- to low latitudes within the northern hemisphere, and even southern oceanic records. It suggests that southern and low-latitude climate conditions are likely important for the termination of HS. Thus, a DAP of about 400–600 years is a precondition for the ASM sub-system to prepare for a new equilibrium. [ABSTRACT FROM AUTHOR]

Climate reconstructions over the last millennium are essential to estimate natural and anthropogenic forcing. Here we present a stalagmite δ18O record from southwestern China, which characterizes changes in the Asian Summer Monsoon (ASM) precipitation over the past 1350 years. Wet climate is clearly identified during the Dark Age Cold Period (DACP) and Little Ice Age (LIA); dry climate is clearly identified during the Medieval Warm Period (MWP) and Current Warm Period (CWP). These precipitation oscillations, except that over the CWP, are remarkably similar to, but strongly antiphase with, those in northwestern China. Over the CWP, our δ18O record, similar to other stalagmite records in East Asia, also exhibits a gradually increasing trend. This trend has been assumed to be caused by anthropogenic temperature warming. Here a better correlation is identified between our record and atmospheric temperature change during the preindustrial and industrial eras. This correlation provides solid evidence for the consistent modulation of the temperature on the ASM precipitation without and with the human-induced forcing. However, this modulation may act in a different manner during the industrial era, which results in the same δ18O variation across East Asia. In sum, our record provides a clear spatial variation of the ASM precipitation and highlights persistent temperature modulation on the ASM without and with anthropogenic emissions. • A new stalagmite record clearly shows a wet DACP and LIA, but dry MWP and CWP in southern China. • Precipitation variations in southern China are antiphase with those in northern China on the multi-centennial scale. • Precipitation in southern China changed in step with atmospheric temperature throughout the last millennium. [ABSTRACT FROM AUTHOR]

• High-resolution stable isotopic records from three stalagmites are used to reconstruct EASM and EAWM changes. • Winter temperature is important for calcite δ13C variability via soil CO 2 production. • The EASM and EAWM variations are negatively correlated at a centennial scale. • The relationship of millennial-scale EASM and EAWM changes are variable. The correlation of East Asian summer and winter monsoons (EASM and EAWM) is believed to be variable at various timescales and under different climate backgrounds. In order to address this issue, high-resolution δ18O (depleted values indicating a strong EASM) and δ13C records (depleted values representing a weak EAWM) from three stalagmites, covering Marine Isotope Stages (MIS) 4 and 3, are reconstructed from an alpine cave in central China. During MIS 4, millennial-scale changes are clear in δ18O and δ13C records, while the δ13C is only characterized by centennial-scale variability across MIS 3. Changes in these speleothem δ13C records are supported by pollen records from the same area, which suggested millennial-scale alternations between conifer and deciduous broadleaf forests during MIS 4 and a stable C3-type vegetation in MIS 3. After detrended, δ18O changes are positively correlated with the δ13C record at a centennial scale, indicating an anti-phase of EASM and EAWM. In early MIS 4, however, an in-phase relationship of EASM and EAWM can be observed at a millennial scale. Thus, an anti-phased EASM/EAWM can be expected at a centennial scale, while a complicated correlation is seen at a millennial scale. These results imply a variable EASM/EAWM phase relationship under varying climatic conditions through the geological records and at different timescales. [ABSTRACT FROM AUTHOR]

The Asian monsoon (AM) is an important atmosphere circulation system of the global climate system, acting as a bridge across high-northern latitude and tropic climates. However, dynamical origins of AM variations during the Holocene remain unclear. Here we present stable isotope records (δ 18 O and δ 13 C) of a Holocene stalagmite from Niu Cave, central China, to address the nature and causes of East Asian summer monsoon (EASM) changes. Our δ 18 O record shows a gradual weakening of the EASM intensity from the middle to the late Holocene, corresponding with a decrease in Northern Hemisphere summer insolation and an enhancement of ENSO activity. The δ 13 C profile exhibits similar variability to δ 18 O record, suggesting that regional hydrological changes were primarily controlled by the large-scale summer monsoon circulation. Power spectrum analyses of δ 18 O and δ 13 C records show that the EASM intensity varies at a dominant periodicity of ~ 830 yr, probably correlated to an ENSO-like cycle. Furthermore, millennial-scale shifts in our records exhibit a strong correlation with that in ENSO proxies over the past 3000 years. The EASM-ENSO relationship may be related to the shifts in the mean position of Walker circulation and western North Pacific subtropical high. Our finding suggests that millennial-scale monsoon changes in the late Holocene are primarily modulated by changes in tropical ocean–atmosphere circulation, rather than variations in the North Atlantic thermohaline circulation. [ABSTRACT FROM AUTHOR]

Two annually-laminated and 230 Th-dated stalagmite oxygen isotope (δ 18 O) records from Dongge Cave, China, provided a high-resolution Asian Summer Monsoon (ASM) history for the past 1200 years. A close similarity between annual band thickness and stable isotope analyses (δ 13 C and δ 18 O) suggests the calcite δ 18 O is most likely a proxy associated with ASM precipitation. The two duplicated stalagmite δ 18 O records show that the ASM varies at a periodicity of ∼220 years, concordant with a dominant cycle of solar activity. A period of strong ASM activity occurred during the Spörer Minimum (1450–1550 A.D.), followed by a striking drop circa 1580 A.D., potentially consistent with the social unrest in the final decades of China's Ming Dynasty (1368–1644 A.D.). Centennial-scale changes in ASM precipitation over the last millennium match well with changes in tropical Atlantic sea surface temperatures (SSTs) and South American summer monsoon precipitation. Our findings suggest that variations in low-latitude monsoon precipitation are probably driven by shifts in the mean position of the intertropical convergence zone (ITCZ), which is further mediated by solar activity and tropical SSTs. [ABSTRACT FROM AUTHOR]

Abstract: High-resolution oxygen isotope records of three stalagmites from Sanbao (central China), Wulu (southern China) and Dashibao (southern China) Caves, based on 876 oxygen isotope measurements and 25 precise 230Th dates, provide a detailed Asian monsoon (AM) history from 32.5 to 20.8kaB.P., spanning the shift between Marine Isotope Stages 3 and 2. The calcite δ18O records, although geographically widespread (about 1000km between them), including the previously-reported Hulu record, are similar in timing, shape, and amplitude. These observations support the idea that changes in speleothem δ18O largely represent variations of precipitation isotopic composition associated with large-scale summer monsoon circulation over a large portion of China. These profiles show four centennial to millennial scale strong summer monsoon events, analogous in timing and structure to Greenland Interstadials 5 through 3 (GIS 5–3). Chronology of the events refines the Hulu record and broadly supports the NGRIP GICC05 timescale. Five weak monsoon events are identified at 31.2, 30.1, 28.1, 25.7 and 24.2kaB.P., all of which correspond to stadial events in Greenland. The 30.1 and 24.2ka events correlate with Heinrich stadials 3 and 2. Furthermore, these events correlate to warm episodes in Antarctic ice cores, indicating that the climatic response to North Atlantic cooling is similar in China and in Antarctica, but in an opposite sense. These observations are consistent with the bi-polar seesaw hypothesis. The strong coupling between AM circulation and climate at both high latitudes at the centennial scale indicates that atmospheric circulation changes are important in transmitting abrupt climate signals globally. [ABSTRACT FROM AUTHOR]

A 67-yr-resolution δ18O profile of a230Th-dated stalagmite from Luoshui Cave, central China, is presented to refine the Asian summer monsoon (ASM) history from 336 to 290 kyr BP. The sub-stages of Marine Isotope Stage 9 (MIS 9) are clearly reflected in the Luoshui δ18O record, in line with changes in the Northern Hemisphere summer insolation (NHSI). The concurrency of eight weak monsoon intervals (WMIs) between 320 and 290 kyr BP and shifts in the Atlantic oceanic circulation suggest that monsoon weakening was forced by northern high-latitude climate oscillations with north-south shifts in the Intertropical Convergence Zone (ITCZ). Spectrum analyses show a cyclic change of 1–4 kyr between 320 and 290 kyr BP, similar to the Dansgaard-Oeschger cycles during the last glacial period. This suggests a relatively unstable monsoon state when the northern ice volume reached intermediate levels. The detrended δ18O agrees well with the δ13C record on the millennial to sub-millennial scales, suggesting a coupling of monsoon climate and cave environment. After removal of the summer insolation signal at 65°N, the residual Luoshui δ18O record is highly similar to orbital- and millennial-scale temperature changes in Antarctica in an anti-phased fashion, revealing the significant influence of Southern Hemispheric climates on ASM intensity. The absence of counterparts of the two WMIs between 315 and 310 kyr BP in Antarctica, however, indicates a complicated teleconnection. • A high resolution and precision dating stalagmite record covered MIS9 in China. • A potential chronologic benchmark for global millennial-scale events in MIS9. • Eight WMIs over MIS9 presented anti-phased relationship with Antarctic temperature. [ABSTRACT FROM AUTHOR]

Observations and models suggest a latitudinal redistribution of precipitation as a result of ongoing global climatic warming. However, the dynamic link between temperature and regional precipitation in the course of natural climatic variability during the current interglacial period remains unclear, especially in the monsoon regions of China. Here we present a reconstruction of a ∼5 year-resolution summer monsoon rainfall record for the past 3200 years, based on 622 pairs of δ18O and δ13C and 29 230Th dates from a stalagmite (Wu37) from Wulu Cave in southern China. A close similarity between the δ18O and δ13C records on centennial to decadal timescales suggests that calcite δ18O is most likely a proxy associated with monsoon precipitation. The record reveals that the Little Ice Age (650 - 100 yr B.P.) was a relatively humid period, with two centennial-scale wet events, compared with the Medieval Warm Period (1050 - 650 yr B.P.). In contrast with previous observations in India and northern China, monsoon precipitation variations indicated by our record and other cave records nearby were inversely related to changes in Northern Hemisphere (NH) temperature over the past two millennia, in particular to variations in the thermal gradient between the Northern and Southern hemispheres. This suggests that NH temperature has an important influence on summer precipitation in southern China, via the interhemispheric thermal gradient and land-ocean thermal contrast. In addition, we find that variations of monsoon rainfall in southern China on multi-centennial to centennial timescales are inversely correlated with observed rainfall in the core monsoon region of India and in the northern fringe of the Asian summer monsoon region in China. This spatial pattern of rainfall variability can be interpreted as a result of the migration of the intertropical convergence zone that is likely dominated by the interhemispheric thermal gradient via cross-equatorial airflows. • Increase of monsoon precipitation in southern China (SC) since the LIA. • Anti-phase relationship between SC precipitation and NH temperature. • A negative correlation between precipitation in SC and India, northern China. • A direct control of NH temperature on the shifts of the ITCZ rainbelt. [ABSTRACT FROM AUTHOR]