Holocene El Niño-Southern Oscillation variability reflected in subtropical Australian precipitation

C Barr; J Tibby; M J Leng; J J Tyler; A C G Henderson; J T Overpeck; G L Simpson; J E Cole; S J Phipps; J C Marshall; G B McGregor; Q Hua; F H McRobie

doi:10.1038/s41598-019-38626-3

Holocene El Niño-Southern Oscillation variability reflected in subtropical Australian precipitation

Sci Rep. 2019 Feb 7;9(1):1627. doi: 10.1038/s41598-019-38626-3.

Authors

C Barr^{1

2}, J Tibby^{3

4}, M J Leng^{5

6}, J J Tyler^{4

7}, A C G Henderson⁸, J T Overpeck⁹, G L Simpson¹⁰, J E Cole¹¹, S J Phipps¹², J C Marshall¹³, G B McGregor¹³, Q Hua¹⁴, F H McRobie¹⁵

Affiliations

¹ Department of Geography, Environment and Population, The University of Adelaide. North Terrace, Adelaide, South Australia, 5005, Australia. cameron.barr@adelaide.edu.au.
² Sprigg Geobiology Centre, The University of Adelaide. North Terrace, Adelaide, South Australia, 5005, Australia. cameron.barr@adelaide.edu.au.
³ Department of Geography, Environment and Population, The University of Adelaide. North Terrace, Adelaide, South Australia, 5005, Australia.
⁴ Sprigg Geobiology Centre, The University of Adelaide. North Terrace, Adelaide, South Australia, 5005, Australia.
⁵ School of Biosciences, Sutton Bonington Campus, University of Nottingham, Leicestershire, LE12 5RD, UK.
⁶ Stable Isotope Facility, Centre for Environmental Geochemistry, British Geological Survey, Nottingham, NG12 5GG, UK.
⁷ Department of Earth Sciences, The University of Adelaide. North Terrace, Adelaide, South Australia, 5005, Australia.
⁸ School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
⁹ School for Environment & Sustainability, The University of Michigan, Ann Arbor, Michigan, 48109, USA.
¹⁰ Institute of the Environmental Change and Society, University of Regina, Saskatchewan, S4S 0A2, Canada.
¹¹ Department of Earth and Environmental Science, The University of Michigan, Ann Arbor, Michigan, 48109, USA.
¹² Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia.
¹³ Queensland Department of Environment and Science, Dutton Park, Queensland, 4102, Australia.
¹⁴ Australian Nuclear Science and Technology Organisation. Locked Bag 2001, Kirrawee DC, New South Wales, 2232, Australia.
¹⁵ School of Mathematics and Statistics, University of Western Australia, Crawley, Western Australia, 6009, Australia.

Abstract

The La Niña and El Niño phases of the El Niño-Southern Oscillation (ENSO) have major impacts on regional rainfall patterns around the globe, with substantial environmental, societal and economic implications. Long-term perspectives on ENSO behaviour, under changing background conditions, are essential to anticipating how ENSO phases may respond under future climate scenarios. Here, we derive a 7700-year, quantitative precipitation record using carbon isotope ratios from a single species of leaf preserved in lake sediments from subtropical eastern Australia. We find a generally wet (more La Niña-like) mid-Holocene that shifted towards drier and more variable climates after 3200 cal. yr BP, primarily driven by increasing frequency and strength of the El Niño phase. Climate model simulations implicate a progressive orbitally-driven weakening of the Pacific Walker Circulation as contributing to this change. At centennial scales, high rainfall characterised the Little Ice Age (~1450-1850 CE) in subtropical eastern Australia, contrasting with oceanic proxies that suggest El Niño-like conditions prevail during this period. Our data provide a new western Pacific perspective on Holocene ENSO variability and highlight the need to address ENSO reconstruction with a geographically diverse network of sites to characterise how both ENSO, and its impacts, vary in a changing climate.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.