1. Spatio-temporal evolution of Australasian monsoon hydroclimate over the last 40,000 years.
- Author
-
Krause, Claire E., Gagan, Michael K., Dunbar, Gavin B., Hantoro, Wahyoe S., Hellstrom, John C., Cheng, Hai, Edwards, R. Lawrence, Suwargadi, Bambang W., Abram, Nerilie J., and Rifai, Hamdi
- Subjects
- *
CLIMATE change models , *MONSOONS , *CLIMATE change - Abstract
Abstract Maritime Continent (MC) convection drives zonal and meridional climate modes, including the Australasian monsoon system, but its role in past global climate change remains uncertain. Here we use speleothem oxygen isotope (δ 18 O) records from a latitudinal transect across the MC, and a new critically located record for southwest Sulawesi, Indonesia, to reconstruct spatial hydroclimate variability in the Australasian monsoon domain over the last 40,000 yr. Our results show that atmospheric convection in the core MC region was reduced from ∼40,000 to 12,000 yr ago and strengthened rapidly only after the inundation of shallow continental shelves in the region, well after the onset of deglaciation. Interestingly, the millennial-scale climatic impacts of North Atlantic Heinrich events are not evident in Sulawesi. Together with climate model simulations, we demonstrate that changes in deep atmospheric convection dominate glacial–interglacial hydroclimate over the MC, whereas latitudinal shifts in the mean location of the InterTropical Convergence Zone control rainfall patterns during abrupt climate changes. Highlights • We present new speleothem results from Sulawesi, Indonesia for the past 40,000 yr. • Atmospheric convection over the Maritime Continent was reduced from ∼40 to 12 kyr. • Convection strengthened following the inundation of shallow continental shelves. • Convection dominates glacial–interglacial hydroclimate over the Maritime Continent. • Latitudinal shifts in the ITCZ control rainfall patterns during abrupt climate events. [ABSTRACT FROM AUTHOR] more...
- Published
- 2019
- Full Text
- View/download PDF