The most vulnerable human environments in Australia and New Zealand are those that are subject to potential coastal or riverine flooding, landslides, or tropical cyclones and other intense storms. Adaptation to natural variability in these cases usually takes the form of planning zones, such as setbacks from coasts and flood levels of particular return periods or engineering standards for buildings and infrastructure. Many of these settlements and structures have long lifetimescomparable to that of anthropogenic climate change. This means that many planning zones and design standards may become inappropriate in a changing climate.
Adaptation in these circumstances depends on costs and benefits, the lifetime of the structures, and the acceptability of redesigned measures or structures (e.g., seawalls). Thus, responses will depend in part on aesthetic and economic considerations; poorer communities, such as many indigenous settlements, will be particularly vulnerable. Conflicts will arise between investors with short time horizons and local government or other bodies who think on longer time scales and may bear responsibility for planning or emergency measures. Complex jurisdictional arrangements often will add to the difficulties of adopting rational adaptation measures (Waterman, 1996).
In an attempt to meet these problems for the Australian coastline, a guide has been developed for response to rising seas and climate change (May et al., 1998), as well as good practice and coastal engineering guidelines (Institution of Engineers, 1998; RAPI, 1998).
Local governments in some parts of Australia and New Zealand are identifying measures they could implement to adapt to climate change. For example, the Wellington Regional Council is required by its Regional Policy Statement to periodically review current knowledge on climate change and possible effects on natural hazards; the Council already allows for climate-induced variability in its flood protection activities (Green, 1999).
The region's health infrastructure is quite strong, and numerous existing adaptations, such as quarantine and eradication of disease vectors, are available to deal with the main changes expected. However, there is concern that already disadvantaged communities, especially indigenous people, may not have equitable access to adaptation measures. Another issue is the question of adaptations to deal with a climatic impact that may cause secondary effects. Examples include adaptations that require more energy production or higher water use, and vector controls that result in reduced population immunity to the disease carried.
Traditional indigenous societies in the region have lived in a close and conscious relationship with their environment (Tunks, 1997; Skertchly and Skertchly, 2000). Australian Aborigines have modified and managed the landscape through the controlled use of low-intensity fire (Kohen, 1995). They have lived in Australia for at least 40,000 years. Thus, they have a long history of adaptation to sea-level rise, which rose by 130 m from the last glacial maximum 18,000 years ago until the present level was reached 6,000 years ago. Memories of these traumatic events are found in oral traditions recorded by early European settlers (Mulvaney and Kamminga, 1999).
With the recognition of indigenous land rights, indigenous people in both countries are now major land managers (Coombs et al., 1990; Langton, 1997) and hence are impacted by and responsible for managing climatic impacts. The importance of their participation in the development of policy and response strategies to climate change is discussed in New Zealand Climate Change Programme (1990) and Tunks (1997), but to date their involvement has been minimal. This is a result partly of greater emphasis in Australia and elsewhere on mitigation of climate change rather than adaptation (Cohen, 1997), lack of indigenous community involvement in climate change research, and the array of other more pressing social issues for such communities (Braaf, 1999).
Basher et al. (1998) draw attention to the vulnerability of the region to external influences arising from climate changein particular, from likely changes in terms of trade (see also Stafford Smith et al., 1999). Increased risk of invasion by exotic pests, weeds, and diseases and possible immigration from neighboring territories rendered uninhabitable by rising sea level are other factors. These issues exist independent of climate change but are likely to be exacerbated by climate change. A variety of adaptations to deal with each problem exist and can be strengthened, but the costs involved and remaining impacts could be considerable.
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