Southern Hemisphere control on Australian monsoon variability during the late deglaciation and Holocene

• Published in: Nature communications 2015-01, Vol.6 (1), p.5916-5916, Article 5916
• Main Authors: Kuhnt, Wolfgang, Holbourn, Ann, Xu, Jian, Opdyke, Bradley, De Deckker, Patrick, Röhl, Ursula, Mudelsee, Manfred
• Format: Article
• Language: English
• Subjects: 704/106; 704/106/829; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms6916

The evolution of the Australian monsoon in relation to high-latitude temperature fluctuations over the last termination remains highly enigmatic. Here we integrate high-resolution riverine runoff and dust proxy data from X-ray fluorescence scanner measurements in four well-dated sediment cores, forming a NE–SW transect across the Timor Sea. Our records reveal that the development of the Australian monsoon closely followed the deglacial warming history of Antarctica. A minimum in riverine runoff documents dry conditions throughout the region during the Antarctic Cold Reversal (15–12.9 ka). Massive intensification of the monsoon coincided with Southern Hemisphere warming and intensified greenhouse forcing over Australia during the atmospheric CO 2 rise at 12.9–10 ka. We relate the earlier onset of the monsoon in the Timor Strait (13.4 ka) to regional changes in landmass exposure during deglacial sea-level rise. A return to dryer conditions occurred between 8.1 and 7.3 ka following the early Holocene runoff maximum. The response of the Australian monsoon to deglacial climate change remains largely unknown due to a dearth of high-resolution climate records. Here, the authors reconstruct precipitation variability in four marine sediment cores and show that Australian monsoon variability closely followed Antarctic warming.