Climate change will influence where it is practical, safe, affordable, comfortable and healthy for Australians to live. Where people live is influenced by many factors, but if people choose or are forced to move to avoid negative impacts, this will affect the job and housing markets and the demand for public services such as transport, health and education. Thinking about who is likely to be most affected, and where, is therefore an important part of determining how Australia should best adapt to climate change.

Direct impacts

1. Rising sea levels will make some low-lying areas impossible, impractical, dangerous or expensive to inhabit, by flooding valuable coastal property, reducing the extent of beaches, increasing coastal erosion and destroying wetlands; and increasing the cost of adaptation through increased construction costs, higher insurance premiums, etc.
2. Reduced rainfall and increased evaporation will make some areas impractical or expensive to inhabit, because there is insufficient water for drinking and/or agriculture.
3. Higher air temperatures will make some areas less comfortable to inhabit.
4. The increasing severity of severe weather events, especially tropical cyclones and associated storm surges, will make living in some areas more difficult, dangerous and expensive (eg, by increasing construction and cooling costs).
5. More frequent and intense bushfires will make it more dangerous or expensive to live on the forested edges of some towns and cities.





Indirect impacts


6. Increased air temperatures and changed rainfall patterns will increase the risk of health-related problems such as heat stroke and mosquito-borne diseases in northern Australia, making it less attractive and more dangerous and expensive to inhabit.
7. The impacts on some ecosystems will flow on to humans through the dependence of some sectors of the economy on relatively stable natural ecosystems - eg, agriculture, forestry and fishing.
8. The above factors (especially the bleaching of coral reefs) and reduced snowfalls[1] will make some areas less attractive to tourists, with flow-on effects to communities dependent on the tourist industry.

Hotspots
The areas most likely to experience reduced liveability[2] and negative economic impacts as a result of these factors are:

• Coastal northern Australia (Cape York to the Kimberley, but especially the Torres Strait Islands)[3] - 1, 3, 4, 6 and 8
• Tropical Queensland - 1, 3, 4, 6 and 8 (especially due to the gradual destruction of the Great Barrier Reef)
• Coastal northern NSW and south-east Queensland (especially the Gold Coast)[4] - 1, 4 and 8
• Murray-Darling basin - 2
• Perth and south-west WA - 2
• Snowy Mountains - 8

Conclusion
If climate change were the only factor to consider, these factors would be likely to lead to a further concentration of population in coastal south-eastern Australia by 2030. This is in spite of the impacts of reduced rainfall and rising ocean levels in this area, and would be due to the likelihood of fewer negative impacts in this part of Australia relative to the remainder. Whether or not this scenario will prove correct, the people who are likely to be most severely affected are those without the economic means, education or skills to change where and how they live.

Notes

• Unless otherwise indicated, the projections on this page are based on CSIRO modelling of the impacts on Australia of nine climate models driven by a range of projected increases in greenhouse gases.[6] These are based in turn on the range of models developed in the Third Assessment Report - Climate Change 2001 of the Intergovernmental Panel on Climate Change (IPCC)
• Climate change is only one of the variables likely to influence population movement in Australia, and no attempt has been made to balance it against other factors: most obviously the nations', and individuals', adaptive capacities; but also such non-climate related changes in the mining and tourism industries, push and pull factors related to state and territory economic growth, the impact of new trade- and defence-related infrastructure, and migration intakes. Therefore, no attempt has been made to quantify the impacts (ie, to estimate how many people may be affected in each area).
• "Sea changers" are still moving to risky areas that will be hit by climate change (all around the coast, but especially northern NSW and the Gold and Sunshine Coasts in Queensland). It might thus be argued that climate change is a factor that people are aware of in deciding where to live, and that they will continue to balance the impacts against other factors that may continue to make such areas attractive. However, it is also possible that they are often unaware of current and potential impacts, or are simply hoping that the worst predictions won't eventuate. This needs more research.
• No attempt has been made to suggest whether the overall population of Australia is likely to rise or fall as a result of climate change. The trends outlined above suggest that, with the negative impacts likely to far outweigh the positives, unless there are major scientific and technological innovations (eg, drought-resistant crops and more water recycling) the continent as a whole is likely to be less liveable than at present. This does not mean that the population is likely to fall, however. Indeed, it could increase for climate-related reasons such as pressure from climate refugees, or for non-climate related reasons.
• Some impacts are already occurring, while others may take decades to become obvious. It should therefore not be presumed that all the impacts discussed on this page will operate simultaneously to influence demographic movements.
• The CSIRO modelling does not take into account any measures introduced between now and 2030 to mitigate the impacts of climate change, since the effects of any mitigation efforts on climate in 2030 will be negligible. On the other hand, neither does it take into account the possibility of greatly accelerated climate change as a result of passing one of a number of possible "tipping points" leading to catastrophic rises in atmospheric and ocean temperatures and ocean levels.[7]

1
In 2001 the CSIRO estimated that "A low-climate-change scenario for 2030 leads to 18% less snow cover and a high-climate-change scenario leads to 66% less cover" (Climate Change Projections for Australia. Climate Impact Group, CSIRO Atmospheric Research, Melbourne, 2001, Fig. 5, 5 [7 September 2006]).

2
"Liveability" here refers to the subjective response of people to their environment in terms of air temperature, humidity and wind speed and frequency, and is based on a comfort zone of 20-24ΊC.

3
"According to the draft fourth Intergovernmental Panel on Climate Change report, written by the world's leading climate scientists and seen by the Herald before its official release next year, the recent king tides exposed the need for better short-term coastal protection and long-term planning to potentially relocate up to half of the 4000 people living on the islands", Liz Minchin, "Going Under", Sydney Morning Herald, 12 August 2006. The CSIRO's Sharing Knowledge program is studying Indigenous experiences of climate change.

7
For example, Melting permafrost may release methane, Sydney Morning Herald, 7 September 2006, referring to recent studies reported in the journals Nature and Science.