Local hydroclimate alters interpretation of speleothem δ18O records

E W Patterson; V Skiba; A Wolf; M L Griffiths; D McGee; T N Bùi; M X Trần; T H Đinh; Q Đỗ-Trọng; G R Goldsmith; V Ersek; K R Johnson

doi:10.1038/s41467-024-53422-y

Local hydroclimate alters interpretation of speleothem δ¹⁸O records

Nat Commun. 2024 Oct 21;15(1):9064. doi: 10.1038/s41467-024-53422-y.

Authors

E W Patterson^{1

2}, V Skiba^{3

4}, A Wolf^{5

6}, M L Griffiths⁷, D McGee⁸, T N Bùi⁹, M X Trần⁹, T H Đinh⁹, Q Đỗ-Trọng¹⁰, G R Goldsmith¹¹, V Ersek¹², K R Johnson⁵

Affiliations

¹ Department of Earth System Science, University of California, Irvine, CA, USA. [email protected].
² Department of Environmental Science, William Paterson University, Wayne, NJ, USA. [email protected].
³ Potsdam Institute for Climate Impact Research, Member of the Leibniz Association, Potsdam, Germany. [email protected].
⁴ Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany. [email protected].
⁵ Department of Earth System Science, University of California, Irvine, CA, USA.
⁶ Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.
⁷ Department of Environmental Science, William Paterson University, Wayne, NJ, USA.
⁸ Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
⁹ Phong Nha- Ke Bang National Park, Phong Nha, Vietnam.
¹⁰ University of Science, Vietnam National University, Hanoi, Vietnam.
¹¹ Schmid College of Science and Technology, Chapman University, Orange, California, USA.
¹² Department of Geography and Environmental Sciences, Northumbria University, Newcastle, United Kingdom.

Abstract

Oxygen isotopes (δ¹⁸O) are the most commonly utilized speleothem proxy and have provided many foundational records of paleoclimate. Thus, understanding processes affecting speleothem δ¹⁸O is crucial. Yet, prior calcite precipitation (PCP), a process driven by local hydrology, is a widely ignored control of speleothem δ¹⁸O. Here we investigate the effects of PCP on a stalagmite δ¹⁸O record from central Vietnam, spanning 45 - 4 ka. We employ a geochemical model that utilizes speleothem Mg/Ca and cave monitoring data to correct the δ¹⁸O record for PCP effects. The resulting record exhibits improved agreement with regional speleothem δ¹⁸O records and climate model simulations, suggesting that the corrected record more accurately reflects precipitation δ¹⁸O (δ¹⁸O_p). Without considering PCP, our interpretations of the δ¹⁸O record would have been misleading. To avoid misinterpretations of speleothem δ¹⁸O, our results emphasize the necessity of considering PCP as a significant driver of speleothem δ¹⁸O.

Grants and funding

1735040/National Science Foundation (NSF)