Publication Date:
2022-05-26
Description:
© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Quaternary Science Reviews 176 (2017): 101-105, doi:10.1016/j.quascirev.2017.09.014.
Description:
Recent studies of stalagmites from the Southern Hemisphere tropics of Indonesia
revealed two shifts in monsoon activity not apparent in records from the Northern Hemisphere
sectors of the Austral-Asian monsoon system: an interval of enhanced rainfall at ~19 ka,
immediately prior to Heinrich Stadial 1, and a sharp increase in precipitation at ~9 ka.
Determining whether these events are site-specific or regional is important for understanding the
full range of sensitivities of the Austral-Asian monsoon. We present a discontinuous 40 kyr
carbon isotope record of stalagmites from two caves in the Kimberley region of the north-central
Australian tropics. Heinrich stadials are represented by pronounced negative carbon isotopic
anomalies, indicative of enhanced rainfall associated with a southward shift of the intertropical
convergence zone and consistent with hydroclimatic changes observed across Asia and the Indo-
Pacific. Between 20-8 ka, however, the Kimberley stalagmites, like the Indonesian record, reveal
decoupling of monsoon behavior from Southeast Asia, including the early deglacial wet period
(which we term the Late Glacial Pluvial) and the abrupt strengthening of early Holocene
monsoon rainfall.
Description:
Funded by grants from the U.S. National Science Foundation Paleo Perspectives on
Climate Change program (AGS-1103413 and AGS-1502917 to RFD) and AGS-1602455 (to
CCU and RFD), the Center for Global and Regional Environmental Research, and Cornell
College (to RFD). CCU acknowledges support from The Investment in Science Fund given
primarily by WHOI Trustee and Corporation Members. Support also received from the
Kimberley Foundation Australia.
Keywords:
Stalagmite
;
Carbon isotope
;
Oxygen isotope
;
Indo-Australian summer monsoon
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
