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

• Published in: Nature Communications
• Main Authors: Kuhnt, Wolfgang, Holbourn, Ann, Xu, Jian, Opdyke, Bradley, De Deckker, Patrick, Roehl, Ursula, Mudelsee, Manfred
• Format: Text
• Language: English
• Published: Nature Publishing Group
• Subjects: envir; geo; Antarctic; The Antarctic; Antarc*; Antarctica
• Online Access: https://doi.org/10.1038/ncomms6916; https://archimer.ifremer.fr/doc/00352/46296/45939.pdf; https://archimer.ifremer.fr/doc/00352/46296/45940.pdf; https://archimer.ifremer.fr/doc/00352/46296/

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 CO2 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.