Living in a variable climate
Dr Greg McKeon, CRC for Greenhouse Accounting, Queensland Department of Natural Resources and Water
prepared for the 2006 Australian State of the Environment Committee, 2006
Australia has a wide range of climate types, including equatorial, tropical, subtropical desert grassland and temperate (Lindesay 2003). The regions in which agricultural and urban developments have occurred have high year-to-year variability in rainfall. During the last 200 years of agricultural and urban settlement, there has been considerable adaptation in terms of land use and infrastructure development in response to increasing awareness of rainfall variability and the demands of an increasing population. Since settlement, the success of agriculture, despite a highly variable climate, has contributed greatly to the development of Australia's economy (Pestana 1993). This success has also highlighted the potential economic sensitivity to climate variability and resource degradation.
Water availability has been a major limitation to agricultural development during the last 200 years. Periods of drought have placed great stress on human and animal welfare, economic production and resource sustainability. The scarcity of water supply in all aspects of Australian agriculture (such as cropping and grazing) has been the driving force behind the development of on-farm water infrastructure to 'drought-proof' properties, as well as the development of large irrigation schemes (such as the Murray and Murrumbidgee regions), earthen tank technologies, and use of the underground water resources of the Great Artesian Basin.
To continue to successfully adapt to climate variability and climate change, the community will need to increase its 'climate literacy' (Botterill 2003, p. 197) so that political, social, economic and environmental decisions are better informed. As explored in this commentary, a major difficulty in achieving this goal of improved climate literacy is that climate science is continuing to discover new knowledge about the global climate system, and Australia's regional climates. Future climate changes are expected, not only due to long-term natural variability of the global climate system, but also due to human-induced influences through increasing greenhouse gas concentration, stratospheric ozone depletion, aerosol emissions and land use change (Burroughs 2003, pp. 92–102).
In assessing how the challenge of 'living in a variable climate' has been, and is being addressed, the commentary presents: an example from the history of Australia's rangelands (Box 1); current case studies of adaptation to anticipated climate change (Box 2); and an assessment of responses to the current drought (Box 3). These case studies provide examples of how the community may continue to plan for, and adapt to, a changing climate.