Climate change is a major driver of change for Australia. Commenting on Australia’s vulnerability, the Intergovernmental Panel on Climate Change (IPCC) noted in 2007:41
Even if adaptive capacity is realized, vulnerability becomes significant for 1–2 °C of global warming. Energy security, health (heat-related deaths), agriculture and tourism have larger coping ranges and adaptive capacity, but they may become vulnerable if global warming exceeded 3 °C.
The indirect effects of climate change are likely to be particularly important for coastal environments and settlements. They include:
- decreased water availability and water security due to reduced rainfall and increased evaporation, reducing run-off to streams and recharge of groundwater systems
- impacts on the coastal zone, such as inundation from sea level rise (see Section 4.3) and changes in the frequency and severity of tidal and storm surges
- damage to energy, water, communications and built infrastructure
- a decline in agricultural and aquacultural productivity due to increased drought, fire and water temperatures
- damage to iconic natural ecosystems, such as the Great Barrier Reef and Kakadu National Park
- a decline in biodiversity.
Climate change could also act in combination with other pressures to challenge the resilience of coastal communities and environments. For example, if commercial fishing, recreational fishing (tourism) or aquaculture were negatively impacted by climate change, a town may be less resilient to other pressures (e.g. a decline in forestry or agricultural activity). The decline in the Western Australian rock lobster fishery, for example, is affecting small coastal communities, and the decrease in economic activity in these communities is being felt in many sectors.
Drawing on information from the IPCC, the CSIRO concluded that the three sectors in the Australian and New Zealand region that are most vulnerable to climate change are coastal communities, water security and natural ecosystems.43
More subtle effects on cultural heritage places may result from changes in atmospheric moisture, wind effects, and climate and pollution acting together.44 Increases in the frequency of heatwaves could see people moving temporarily to coastal areas to take advantage of sea breezes, which would exacerbate the existing population pressures. Extension in the range of various disease vectors (notably mosquitoes) is a direct threat to coastal settlements and could lead to major habitat modification and/or use of chemicals for vector control. In some areas, climate change is expected to have the positive effect of reducing cold weather, which could also add to coastal population pressures.
Chapter 3: Atmosphere discusses the potentially adverse effects of climate change, via extreme events such as bushfires and dust storms, on respiratory and cardiovascular health, both acute and chronic. Coastal areas already struggle to maintain adequate health facilities for their growing populations.