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Abstract: This study analyzed the geographical patterns of heat-related mortality among the population aged 65 and over within the metropolitan area of Sydney, Australia between 1993 and 2004, and evaluated the role of some physical and socio-demographic risk factors associated with it. The effect of temperature on all-cause mortality during unusually hot days was investigated using spatial analytic techniques, such as cluster analysis and spatial regression analysis. Generalized Linear Models (GLMs) were used to investigate the role of daily average temperature, ozone (O3) and particulate matter of diameter less than 10μm (PM10) at the regions that showed a significant increase in mortality on unusually hot days. Spatial variation in mortality on unusually hot days was observed among the population 65 and over. Elderly people living within 5–20km south-west and west of the Sydney Central Business District (CBD) were found to be more vulnerable. However, analysis using GLMs showed temperature to be a significant modifier of daily mortality in the region to the south-west of the CBD only. O3 and PM10 were found to be non-significant factors in the regions where air pollutants were studied. Socio-economic status and the proportion of vegetation or developed land in each Statistical Local Area (SLA) were also not a significant factor explaining the increased mortality. A combination of social and environmental factors may be at play. Our results suggest an effect of temperature on mortality of the elderly population in Sydney Statistical Division at the SLA level. More spatially-based research would be beneficial once climate datasets with improved spatial coverage become available. [Copyright &y& Elsevier]

Abstract: Studies of heat-related mortality have been predominantly based on analyses of underlying cause of death as the single indicator of a population''s vulnerability to high temperatures. Examination of both underlying and associated causes of death could provide a more comprehensive understanding of the population at risk. This study analyzes the impact of high temperatures on mortality in Sydney, Australia, during the warmer six months (October–March) between 1993 and 2004, using the underlying and associated cause of death due to all-cause, circulatory, and respiratory disease. Some mortality datasets were also divided into two age groups, 0–64 and 65+. A generalized linear model assuming negative binomial distribution was constructed for the daily mortality counts using daily maximum temperature and hourly maximum concentrations of ozone (O3) and particulate matter (PM10) as covariates. With the air pollution terms in a model, the change in mortality was estimated to be between 4.5% and 12.1% for a 10°C increase in maximum daily temperature, depending on mortality dataset. When air pollutants were removed from a model, the above mortality percentages changed by −1.1% to 0.9%. When both underlying and associated causes of death were considered, the effect remained the same or became lower. Maximum temperature has been found to have a significant effect on mortality in Sydney, with PM10 and O3 confounding the association. [Copyright &y& Elsevier]

Green infrastructure has the potential to cool urban environments and reduce the health burden due to heatwaves. This study develops a new method to quantify the benefits of urban heat mitigation technologies on human heat balance and population mortality. The Heat Health Impact (HHI) method is based on the state-of-the-art, multi-parameter model, Universal Thermal Climate Index (UTCI). A proof-of-concept exercise applied the HHI method to Sydney, Australia (population = 5.7 million). All available weather stations (10) were selected for full spatial coverage of the Sydney region (12,367 km2), and average hourly UTCI was calculated from meteorological observations spanning the entire year 2017. In the baseline analysis, average daily UTCI values were calculated for each of the 10 observation sites, and then spatially interpolated across the entire Sydney region for Feb 9, 2017, a representative heatwave day for Sydney. Three different greening intervention scenarios were investigated, and daily average change in UTCI (ΔUTCI) was calculated under each by comparison with the baseline scenario; this ΔUTCI was named Urban Cooling Effect (UCE). We implemented a health impact assessment methodology to estimate the change in attributable mortality due to each greening scenario for the Sydney GMR population for the representative heatwave day. Urban greening infrastructure scenarios reduced daily average UTCI between −0.2 and −1.7 °C on the heatwave day, with the health impact assessment indicating heat attributable deaths reducing up to 11.7 per day across the Sydney GMR compared to the baseline scenario. Our results highlight the health benefits of greening infrastructure to cool urban environments. • A new method developed to quantify the benefits of urban greening on mortality. • Urban greening infrastructure reduced daily average UTCI between −0.2 and −1.7 °C. • Adaptation strategies reduced deaths up to 11.7 per day in Sydney during heatwave. [ABSTRACT FROM AUTHOR]