Carbonate cave deposits in India and China are assumed to record the intensity of monsoon precipitation, because the δ18O of the carbonate tracks the isotopic signature of precipitation. These records show spatially coherent variability throughout the last ice age and suggest that monsoon strength was altered during the millennial-scale climate variations known as Dansgaard–Oeschger events and during the Heinrich cooling events. Here we use a numerical climate model with an embedded oxygen-isotope model to assess what caused the shifts in the oxygen-isotope signature of precipitation during a climate perturbation designed to mimic a Heinrich event. Our simulations show that a sudden increase in North Atlantic sea-ice extent during the last glacial period leads to cooling in the Northern Hemisphere, reduced precipitation over the Indian basin and weakening of the Indian monsoon. The precipitation is isotopically heavier over India and the water vapour exported to China is isotopically enriched. Our model broadly reproduces the enrichment of δ18O over Northern India and East Asia evident in speleothem records during Heinrich events. We therefore conclude that changes in the δ18O of cave carbonates associated with Heinrich events reflect changes in the intensity of Indian rather than East Asian monsoon precipitation.
At a glance
- Heinrich events: Massive late Pleistocene detritus layers of the North Atlantic and their global climate imprint. Rev. Geophys. 42, RG1005 (2004).
- Origin and consequences of cyclic ice rafting in the Northeast Atlantic Ocean during the past 130,000 years. Quat. Res. 29, 142–152 (1988).
- Evidence for massive discharges of icebergs into the North Atlantic Ocean during the last glacial period. Nature 360, 245–249 (1992). et al.
- The southwest Indian monsoon over the last 18000 years. Clim. Dyn. 12, 213–224 (1996). , , , &
- Rapid changes of glacial climate simulated in a coupled climate model. Nature 409, 153–158 (2001). &
- Sensitivity of the Atlantic Intertropical Convergence Zone to Last Glacial Maximum boundary conditions. Paleoceanography 18, 1094 (2003). , &
- Response of East Asian climate to Dansgaard/Oeschger and Heinrich events in a coupled model of intermediate complexity. J. Geophys. Res.-Atmos. 112, D06117 (2007). , , &
- Can North Atlantic sea ice anomalies account for Dansgaard–Oeschger climate signals? J. Clim. 23, 5457–5475 (2004). , &
- Millennial- and orbital-scale changes in the East Asian monsoon over the past 224,000 years. Nature 451, 1090–1093 (2008). et al.
- Distinct climate change synchronous with Heinrich event one, recorded by stable oxygen and carbon isotopic compositions in stalagmites from China. Quat. Res. 69, 306–315 (2008). et al.
- Timing, duration, and transitions of the Last Interglacial Asian Monsoon. Science 304, 575–578 (2004). et al.
- Variability of Southwest Indian summer monsoon precipitation during the Bølling–Ållerød. Geology 33, 813–818 (2005). et al.
- A high-resolution absolute-dated Late Pleistocene monsoon record from Hulu Cave, China. Science 294, 2345–2348 (2001). et al.
- A penultimate glacial monsoon record from Hulu Cave and two-phase glacial terminations. Geology 34, 217–220 (2006). et al.
- Ice age terminations. Science 326, 248–252 (2009).
- Stable isotopes in precipitation. Tellus 16, 436–468 (1964).
- Strong influence of water vapor source dynamics on stable isotopes in precipitation observed in Southern Meghalaya, NE India. Earth Planet. Sci. Lett. 292, 212–220 (2010). et al.
- High-resolution absolute-dated Indian Monsoon record between 53 and 36 ka from Xiaobailong Cave, southwestern China. Geology 34, 621–624 (2009). et al.
- High resolution characterization of the Asian Monsoon between 146,000 and 99,000 years B.P. from Dongge Cave, China and global correlation of events surrounding Termination II. Palaeogeogr. Palaeoclimatol. Palaeoecol. 236, 20–38 (2006). et al.
- East Asian summer monsoon variability during Marine Isotope Stage 5 based on speleothem delta O-18 records from Wanxiang Cave, central China. Palaeogr. Palaeoclimatol. Paleoecol. 236, 5–19 (2006). , , &
- Lessons learned from oxygen isotopes in modern precipitation applied to interpretation of speleothem records of paleoclimate from eastern Asia. Earth Planet. Sci. Lett. 295, 219–230 (2010). , , &
- 1–36 (AGU monograph 78, 1993). , & in Climate Change in Continental Isotopic Records (eds Swart, P. K., Lohmann, K. C., Mckenzie, J. A. & Savin, S.)
- Sources of Holocene variability of oxygen isotopes in paleoclimate archives. Clim. Past 5, 441–455 (2009). &
- Last Glacial Maximum and Holocene climate in CCSM3. J. Clim. 19, 2526–2544 (2009). et al.
- Rates of thermohaline recovery from freshwater pulses in modern, Last Glacial Maximum, and greenhouse warming climates. Geophys. Res. Lett. 34, L07708 (2007). , , &
- Revisiting the absolute calibration of the Greenland ice-core age-scales. Clim. Past 4, 295–302 (2008).
- The formulation and atmospheric simulation of the Community Atmosphere Model version 3 (CAM3). J. Clim. 19, 2144–2161 (2006). et al.
- 2009). & Isoscapes: Understanding Movement, Pattern, and Process on Earth Through Isotope Mapping (Springer,
- Abrupt climate shifts in Greenland due to displacements of the sea ice edge. Geophys. Res. Lett. 32, L19702 (2005). , , &
- 6th edn (ed. Fleischer, M.) (Geol. Surv. Prof. Pap. U.S., 1977). & in Data of Geochemistry
- The East Asian summer monsoon: An overview. Meteorol. Atmos. Phys. 89, 117–142 (2005). &
- Seven million years of wind and precipitation variability on the Chinese Loess Plateau. Earth Planet. Sci. Lett. 297, 525–535 (2010). , , , &
- Correlation between Arabian Sea and Greenland climate oscillations of the past 110,000 years. Nature 393, 54–57 (1998). , &
- The effect of millennial-scale changes in Arabian Sea denitrification on atmospheric CO2. Nature 415, 159–162 (2002). , &
- Indian Ocean climate and an absolute chronology over Dansgaard/Oeschger events 9 to 13. Science 301, 1365–1367 (2003). , , , &
- Water vapour source impacts on oxygen isotope variability in tropical precipitation. Clim. Past 6, 325–343 (2010). , , &
- Impact of freshwater release in the North Atlantic under different climate conditions in an OAGCM. J. Clim. 22, 6377–6403 (2009). , , , &
- Regime transitions of steady and time-dependent Hadley circulations: Comparison of axisymmetric and eddy-permitting simulations. J. Atmos. Sci. 67, 1643–1654 (2010). &
- Dominant control of the South Asian monsoon by orographic insulation versus plateau heating. Nature 463, 218–223 (2010). &
- Orographic controls on climate and paleoclimate of Asia: Thermal and mechanical roles for the tibetan plateau. Annu. Rev. Earth Planet. Sci. 38, 77–102 (2010). , &
- Annular variations in moisture transport mechanisms and the abundance of delta O-18 in Antarctic snow. J. Geophys. Res.-Atmos. 107, 4742 (2002). &
- Supplementary Information (1.30MB)