Strong coupling of Asian Monsoon and Antarctic climates on sub-orbital timescales.
There is increasing evidence that millennial-scale climate variability played an active role on orbital-scale climate changes, but the mechanism for this remains unclear. A (230)Th-dated stalagmite δ(18)O record between 88 and 22 thousand years (ka) ago from Yongxing Cave in central China characterizes changes in Asian monsoon (AM) strength. After removing the 65°N insolation signal from our record, the δ(18)O residue is strongly anti-phased with Antarctic temperature variability on sub-orbital timescales during the Marine Isotope Stage (MIS) 3. Furthermore, once the ice volume signal from Antarctic ice core records were removed and extrapolated back to the last two glacial-interglacial cycles, we observe a linear relationship for both short- and long-duration events between Asian and Antarctic climate changes. This provides the robust evidence of a link between northern and southern hemisphere climates that operates through changes in atmospheric circulation. We find that the weakest monsoon closely associated with the warmest Antarctic event always occurred during the Terminations. This finding, along with similar shifts in the opal flux record, suggests that millennial-scale events play a key role in driving the deglaciation through positive feedbacks associated with enhanced upwelling and increasing CO2.
Key Laboratory of Virtual Geographic Environment, Nanjing Normal University, Nanjing 210023, China.|Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application, Nanjing 210023, China.
Shitao
S
Chen
Key Laboratory of Virtual Geographic Environment, Nanjing Normal University, Nanjing 210023, China.|Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application, Nanjing 210023, China.
Yongjin
Y
Wang
Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China.|Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Hai
H
Cheng
Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA.
R Lawrence
RL
Edwards
Earth Observatory of Singapore, Nanyang Technological University, Nanyang Avenue 639798, Singapore.
Xianfeng
X
Wang
Key Laboratory of Virtual Geographic Environment, Nanjing Normal University, Nanjing 210023, China.|State Key Laboratory Cultivation Base of Geographical Environment Evolution, Jiangsu Province, Nanjing 210023, China.
Xinggong
X
Kong
Key Laboratory of Virtual Geographic Environment, Nanjing Normal University, Nanjing 210023, China.|State Key Laboratory Cultivation Base of Geographical Environment Evolution, Jiangsu Province, Nanjing 210023, China.
Dianbing
D
Liu