Structural segmentation controlled the 2015 Mw 7.8 Gorkha earthquake rupture in Nepal

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 230Th-dated stalagmite δ18O record between 88 and 22 thousand years (ka) ago from Yongxing Cave in central China characterizes...

Full description

Bibliographic Details
Published in:Geology
Main Authors: Hubbard, Judith, Almeida, Rafael, Foster, Anna, Sapkota, Soma Nath, Bürgi, Paula, Tapponnier, Paul
Other Authors: Earth Observatory of Singapore, Asian School of the Environment
Format: Article in Journal/Newspaper
Language:English
Published: 2016
Subjects:
Moe
Online Access:http://hdl.handle.net/10220/50430
https://doi.org/10.1130/G38077.1
Description
Summary: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 230Th-dated stalagmite δ18O 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 δ18O 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. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) Published version