Climate change and irrigated agriculture: the case of the
Murray-Darling Basin in Australia
The analysis undertaken by climate scientists and summarized in the Fourth
Assessment Report of the Intergovernmental Panel on Climate Change (IPCC)
(IPCC 2007a,b,c) leaves little doubt that human action is causing changes in the
global climate, and that these changes will continue throughout the 21st century.
Attention has therefore turned to assessment of the likely effects of climate
change, and to the options for mitigation and adaptation.
Projections of climate change for the Murray-Darling Basin in Australia suggest
that climate change is likely to result in lower rainfall and higher evaporation
(Garnaut 2008). The frequency of droughts is also likely to increase. Climate
change will exacerbate existing problems arising from the excessive expansion of
irrigated agriculture.
The prevalence of severe drought conditions in the Basin since 2002 has been
interpreted as evidence that climate change is already under way, although it is
not clear to what extent this change is driven by anthropogenic global warming.
The Wentworth Group of Concerned Scientists (2006) states:
Our continent is getting hotter, and rainfall patterns have
changed significantly ... And science is warning us of
further uncertainty as a result of climate change. This
change in climate may be part of a natural cycle or it
might be caused by climate change or it might be a
combination of both.
More recent evidence suggests that climate change is already a major factor in
reducing rainfall (South-Eastern Australia Climate Initiative 2008).