Deaths in Australia Attributable to Climate Change, Now and to 2100

Abstract

Background/Aims: Deaths from heat extremes are already important in Australia, and will increase under global warming. A total of 1500 people die from heat extremes in Australian cities and this could treble by midcentury (Research Australia 2007). Many researchers have estimated response functions relating mortality to temperature extremes, including in Australia. For example, Vaneckova et al (2008) estimated that in Sydney the increase in mortality is between 4.5% and 12.1% for a 10degreeC increase in maximum daily temperature. Estimates for each city and state in Australia are reported elsewhere in this conference work (Dear, ISEE 2010). Method(s): Age-specific response functions estimated were derived for each state and each capital city in Australia from 16 years of historical mortality data in relation to weather records. The frequency distributions of daily temperatures in 1980-1995 were shifted according to each IPCC climate change scenario, downscaled, to give local mortality estimates from the present to 2100 as the population profile changes. Deaths attributable to climate change were calculated by subtracting mortality estimates under a hypothetical scenario in which the 1990 climate applies through this century. Result(s): The greatest negative impacts of temperature-related death will be in the hotter northern cities of Australia. In colder cities to the south, reduction in cold-related deaths will dominate in the first half of the century, but will be outweighed by increases in heat-related deaths by the end of the century. Conclusion(s): Assessing the impact of climate change on mortality demands attention both to local variation in anticipated climate change, and to the differing susceptibility of local populations.