High-resolution stalagmite reconstructions of Australian-Indonesian monsoon rainfall variability during Heinrich stadial 3 and Greenland interstadial 4

• Published in: Earth and Planetary Science Letters
• Main Authors: Lewis, Sophie C., Gagan, Michael K., Ayliffe, Linda K., Zhao, Jian-xin, Hantoro, Wahyoe S., Treble, Pauline C., Hellstrom, John C., LeGrande, Allegra N., Kelley, Maxwell, Schmidt, Gavin A., Suwargadi, Bambang W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier BV 2011
• Subjects: Speleothem; Isotopes; Trace elements; Heinrich stadial 3; Monsoon; Intertropical convergence zone (ITCZ); 1901 Earth and Planetary Sciences (miscellaneous); 1906 Geochemistry and Petrology; 1908 Geophysics; 1912 Space and Planetary Science; Greenland; North Atlantic
• Online Access: https://espace.library.uq.edu.au/view/UQ:241122

Little is known about the possible teleconnections between abrupt climatic changes originating in the North Atlantic and precipitation dynamics in the Australian-Indonesian summer monsoon (AISM) domain. We examine the climatic impacts of Heinrich stadial 3 (HS3) and Greenland interstadials 4 and 3 (GIS4/3) on AISM-associated precipitation through a high-resolution analysis of stable isotope (delta O-18, delta C-13) and trace element (Mg/Ca, P/Ca) ratios in a stalagmite from Liang Luar cave, Flores, Indonesia. Sixteen high precision Th-230 dates indicate that stalagmite LR07-E1 grew rapidly (similar to 0.3-1.0 mm/yr) in two phases between similar to 31.5-30.1 ka and similar to 27.8-25.6 ka, separated by a similar to 2.3 kyr unconformity. Temporally consistent abrupt responses occur in the Flores record during HS3 and GIS4, which are coherent with changes in stalagmite delta O-18 records from China and Brazil. The response of low-latitude precipitation to HS3 cooling and GIS4 warming, as demonstrated by the widely separated sites, comprises three distinct simplified phases: (1) a strong southward migration of the ITCZ during HS3 is associated with a decrease in rainfall at Liang Luar cave and in China, while wetter conditions are reconstructed from Brazil, (2) represents the peak of HS3 impacts and an extended hiatus begins in the Flores record and (3) where suggested dry conditions at Liang Luar throughout GIS4 form part of a coherent north-south anti-phasing in precipitation changes. The reconstructed changes are also broadly consistent with NASA GISS ModelE-R simulations of a Heinrich-like freshwater perturbation in the North Atlantic basin, which produces a southward shift in the ITCZ. The relationship between the palaeoclimate records indicates that atmospheric teleconnections rapidly propagate and synchronise climate change across the hemispheres during periods of abrupt climate change. Our findings augment recent proposals that large-scale atmospheric re-organisations during stadials and interstadials play a key role in driving changes in atmospheric CO2 concentration, air temperature and global climate change. (C) 2011 Elsevier B.V. All rights reserved.