Roger Jones (Australia) 1
1 - Victoria University Melbourne
The Victorian Department of Health and Human Services (Australia) commissioned the above scoping study, finalised in 2017. It aimed to inform future research, policy development and programs within the department and where climate change may affect the health and wellbeing of Victorians. It was conducted through literature survey of reports and scholarly literature and some data analysis.
The study focused on the social determinants of housing, the urban environment, employment, and food security. It began with the standard division of health impacts into direct, indirect and referred or primary, secondary and tertiary. Direct climate impacts in developed countries are comparatively low, the main reason why climate-related health impacts have a low profile. In Australia, the major direct risks are heatwaves, flood, fire and storm: tropical and mid-latitude. Early warning systems are the most economically effective tools for managing direct health impacts, but beyond that, gains become more difficult to achieve.
A survey of acute and seasonal heat and cold mortality and morbidity showed that seasonal cold outweighed heat health risks by up to 10:1 but that heat risks were mostly direct and cold risks mostly indirect. Two types of temperature-health impact models in use were identified: acute and seasonal. Acute risks are mainly heat-related, as in all countries with Mediterranean climates. Seasonal risks are related to cool-season disease burdens and summer-winter differences. Similar warm-cool season disease burdens in tropical climates suggest that absolute temperatures are not a factor. Current models that project net benefits from future heat and cold mortality are flawed, and in Australia, increases in heat mortality are already outstripping any benefits of cool season warming. These flaws will also affect the modelling of temperature-related health impacts in Europe.
Overall, vulnerability is influenced by age, location, pre-existing medical conditions, and activities and behaviour. These are strongly influenced by social determinants. The predictive capacity for estimating future health impacts is low, but working through social determinants of vulnerability offers great promise for a learning by doing approach that integrates programs for housing, urban environments, employment and food security into a climate-aware portfolio of activities. The economic challenge is to quantify the benefits of these activities, many of which look to be highly cost-effective. Early indications are that population health and wellbeing can be improved with net benefits to the economy. The findings will be of interest to health professionals and policy makers in all developed countries.