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Title: Multi-proxy validation of glacial-interglacial rainfall variations in southwest Sulawesi
Abstract Speleothem δ 18 O is widely used as a proxy for rainfall amount in the tropics on glacial-interglacial to interannual scales. However, uncertainties in the interpretation of this renowned proxy pose a vexing problem in tropical paleoclimatology. Here, we present paired multi-proxy geochemical measurements for stalagmites from southwest Sulawesi, Indonesia, and confirm changes in rainfall amount across ice age terminations. Collectively, the stalagmites span two glacial-interglacial transitions from ~380,000 to 330,000 and 230,000 to 170,000 years ago. Mg/Ca in the slow-growing stalagmites is affected by water moving through the karst and prior calcite precipitation, making it a good proxy for changes in local rainfall. When paired, Mg/Ca and δ 18 O corroborate prominent shifts from drier glacials to wetter interglacials in the core of the Australasian monsoon domain. These shifts in rainfall occur 4,000-7,000 years later than glacial-interglacial increases in global temperature and the associated response of Sulawesi vegetation, determined by speleothem δ 13 C.  more » « less
Award ID(s):
2202913
PAR ID:
10451306
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Communications Earth & Environment
Volume:
4
Issue:
1
ISSN:
2662-4435
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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