Conclusions implications for sustainable development

An assessment of aggregate vulnerability for key sectors of the region is given in Figure 11.4, as a function of potential global warming. It synthesises relevant information in Sections 11.2 to 11.5 about current sensitivity, coping ranges, potential impacts, adaptive capacity and vulnerability. It follows similar diagrams and concepts published elsewhere (Jones et al., 2007) and emulates the 'Reasons for Concern' diagram (Figure SPM-3) in the TAR Synthesis Report. Since most impact assessments in the available literature do not allow for adaptation, the yellow band in Figure 11.4 is indicative only. In line with Chapter 19, vulnerability is assessed using criteria of: magnitude of impact, timing, persistence and reversibility, likelihood and confidence, potential for planned adaptation, geographical distribution and importance of the vulnerable system. Ecosystems, water security and coastal communities of the region have a narrow coping range. Even if adaptive capacity is realised, vulnerability becomes significant for 1.5 to 2.0°C of global warming. Energy security, health (heat-related deaths), agriculture and tourism have larger coping ranges and adaptive capacity, but they become vulnerable if global warming exceeds 3.0°C. The three key vulnerability factors identified in Article 2 of the United Nations Framework Convention on Climate Change (UNFCCC)

- natural ecosystems, sustainable development and food security

- are also shown in Figure 11.4.

When these climate change impacts are combined with other non-climate trends (see Section 11.3.2), there are some serious implications for sustainability in both Australia and New Zealand. Climate change is very likely to threaten natural ecosystems, with extinction of some species. There are limited planned adaptation options, but the resilience of many ecosystems can be enhanced by reducing non-climatic stresses such as water pollution, habitat fragmentation and invasive species. In river catchments, where increasing urban and rural water demand has already exceeded sustainable levels of supply, ongoing and proposed adaptation strategies (see Section 11.2.5) are likely to buy some time. Continued rates of coastal development are likely to require tighter planning and regulation if they are to remain sustainable. Climate change is very likely to increase peak energy demand during heatwaves, posing challenges for sustainable energy supply. A substantial public health and community response is likely to be needed in order to avoid an increase of several thousand heat-related deaths per year.

Large shifts in the geographical distribution of agriculture and its services are very likely. Farming of marginal land in drier regions is likely to become unsustainable due to water shortages, new biosecurity hazards, environmental degradation and social disruption. In areas that are likely to become wetter and less frosty, it may be possible to grow new crops or those displaced from other regions. Adaptation has the capacity to capture these benefits; they are unlikely to accrue without investment in the adaptation process. Food security is very likely to remain robust,

2100 2200 Year

Coping range Adaptive capacity Vulnerability

Figure 11.4. Vulnerability to climate change aggregated for key sectors in the Australia and New Zealand region, allowing for current coping range and adaptive capacity. Right-hand panel is a schematic diagram assessing relative coping range, adaptive capacity and vulnerability. Left-hand panel shows global temperature change taken from the TAR Synthesis Report (Figure SPM-6). The coloured curves in the left panel represent temperature changes associated with stabilisation of CO2 concentrations at 450 ppm (WRE450), 550 ppm (WRE550), 650 ppm (WRE650), 750 ppm (WRE750) and 1,000 ppm (WRE1000). Year of stabilisation is shown as black dots. It is assumed that emissions of non-CO2 greenhouse gases follow the SRESA1B scenario until 2100 and are constant thereafter. The shaded area indicates the range of climate sensitivity across the five stabilisation cases. The narrow bars show uncertainty at the year2300. Crosses indicate warming by 2100 for the SRES B1, A1B and A2 scenarios.

2100 2200 Year

Coping range Adaptive capacity Vulnerability

Figure 11.4. Vulnerability to climate change aggregated for key sectors in the Australia and New Zealand region, allowing for current coping range and adaptive capacity. Right-hand panel is a schematic diagram assessing relative coping range, adaptive capacity and vulnerability. Left-hand panel shows global temperature change taken from the TAR Synthesis Report (Figure SPM-6). The coloured curves in the left panel represent temperature changes associated with stabilisation of CO2 concentrations at 450 ppm (WRE450), 550 ppm (WRE550), 650 ppm (WRE650), 750 ppm (WRE750) and 1,000 ppm (WRE1000). Year of stabilisation is shown as black dots. It is assumed that emissions of non-CO2 greenhouse gases follow the SRESA1B scenario until 2100 and are constant thereafter. The shaded area indicates the range of climate sensitivity across the five stabilisation cases. The narrow bars show uncertainty at the year2300. Crosses indicate warming by 2100 for the SRES B1, A1B and A2 scenarios.

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