A palaeoclimatic rainfall history from Lake Broadwater, southeast Queensland, Australia

Cottrill, D. A. and Ribbe, J. and Maron, M. and Jacobsen, G. (2015) A palaeoclimatic rainfall history from Lake Broadwater, southeast Queensland, Australia. Proceedings of the Royal Society of Queensland, 119. pp. 35-43. ISSN 0080-469X

Abstract

A palaeoclimatic Holocene rainfall history is reported for Lake Broadwater in southeast Queensland, Australia. This naturally-occurring semi-permanent freshwater lake is part of the Condamine-Balonne Catchment on the Darling Downs. It is an important natural habitat for waterbirds and other wildlife, but it dried-out completely during the Australian Millennium Drought. Lake sediments were sampled to a depth of about 1.7 m from the centre of the lake in March 2007. A detailed chronology developed from radiocarbon (14C) dating indicates that sedimentation was fairly constant into the lake and averaged ~0.16 mm year-1 since about 11 kyr cal B.P. An interpretation of the palaeoclimatic record indicates higher rainfall and moist conditions prevailed from ~11 kyr to ~3.5 kyr cal B.P., followed by lower rainfall, decreasing further from ~2.2 kyr cal B.P to the present day. This change to drier conditions most likely reflects an increase in El Niño–Southern Oscillation (ENSO) cycles which began in the mid–late Holocene and has been identified from other proxy records elsewhere in eastern Australia. The change to a lower rainfall regime suggests large-scale ocean/atmospheric circulation changes affecting not only coastal regions, but also inland regions of eastern Australia including the northern parts of the Murray–Darling Basin.


Statistics for USQ ePrint 27433
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: Permanent restricted access to Published version in accordance with the copyright policy of the publisher.
Faculty / Department / School: Current - Faculty of Health, Engineering and Sciences - School of Agricultural, Computational and Environmental Sciences
Date Deposited: 02 Feb 2016 05:50
Last Modified: 01 Jul 2016 03:00
Uncontrolled Keywords: Australia, rainfall, palaeoclimatology, climate, Holocene, El Nino Southern Oscillation
Fields of Research : 04 Earth Sciences > 0406 Physical Geography and Environmental Geoscience > 040605 Palaeoclimatology
04 Earth Sciences > 0401 Atmospheric Sciences > 040105 Climatology (excl.Climate Change Processes)
Socio-Economic Objective: D Environment > 96 Environment > 9603 Climate and Climate Change > 960304 Climate Variability (excl. Social Impacts)
URI: http://eprints.usq.edu.au/id/eprint/27433

Actions (login required)

View Item Archive Repository Staff Only