Abstract
Identification of palaeo-drought episodes in the catchments of the Snowy Mountains Hydro Scheme and Murray-Darling Basin, Australia
Australian and New Zealand Geomorphology Group: Program and Abstracts, p.61
Biennial Conference of the Australian and New Zealand Geomorphology Group, 13th (Queenstown, Australia, 10-Feb-2008 - 15-Feb-2008)
2008
Abstract
Periods of prolonged drought are an intrinsic feature of the Australian landscape (McKeon et al., 2004) and have major environmental, societal and economic effects. These droughts may be the result of inter-annual to multi-decadal variability in regional weather patterns that are the result of teleconnections such as the El Niño Southern Oscillation (ENSO) that operates on a 3 to 7 year cycle and/or the Pacific Decadal Oscillation that changes phase every 20-50 years (Power et al., 1999). This natural variability may in turn be superimposed on millennial scale variability in climate. Accordingly, the instrument record which spans approximately 100 years in most locations is often too short to confirm the cyclic nature of droughts and longer term trends in precipitation. This information is required to more accurately predict future climate variability and the possible impacts of global warming so that better informed natural resource management planning occurs. In this study we develop a dust deposition chronology extracted from alpine peat deposits in the Snowy Mountains, New South Wales to serve as proxy for drought in the catchments of the Snowy Hydro Scheme. This is possible because the occurrence of dust storms in Australia is inherently linked to the degree of aridity (McTainsh et al., 1989). Results show variability in dust deposition through time, indicating that the climate of southeast Australia including the Murray-Darling Basin (MDB) has experienced marked changes in aridity over the last 7000 years. In the past 2500 years the basin experienced a ∼1500 year period characterised by pronounced swings in climate including severe droughts, while the MDB has become more arid over the last 300 years. This is recorded as an increased trend in dust deposition preserved in the peat and suggests that the severity of future interannual to multi-decadal droughts may increase as part of this longer term trend of increased aridity in southeastern Australia. The effects of this natural increase in drought severity may be made worst by the predicted impacts of climate change due to global warming
Details
- Title
- Identification of palaeo-drought episodes in the catchments of the Snowy Mountains Hydro Scheme and Murray-Darling Basin, Australia
- Authors
- Samuel K Marx (Author) - University of QueenslandH A McGowan (Author) - University of QueenslandJ Denholm (Author) - Snowy Hydro Ltd.
- Contributors
- T Cohen (Editor)I Houshold (Editor)
- Publication details
- Australian and New Zealand Geomorphology Group: Program and Abstracts, p.61
- Conference details
- Biennial Conference of the Australian and New Zealand Geomorphology Group, 13th (Queenstown, Australia, 10-Feb-2008 - 15-Feb-2008)
- Publisher
- Australian and New Zealand Geomorphology Group, Inc.
- Organisation Unit
- University of the Sunshine Coast, Queensland
- Language
- English
- Record Identifier
- 99449699402621
- Output Type
- Abstract
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