Extreme heat and cultural and linguistic minorities in Australia: perceptions of stakeholders

Temporal changes in temperature-related mortality in relation to the establishment of the heat-health alert system in Victoria, Australia

Extreme heat alerts are the most common form of weather forecasting services used in Australia, yet very limited studies have documented their effectiveness in improving health outcomes. This study aimed to examine the temporal changes in temperature-related mortality in relation to the activation of the heat-health alert and response system (HARS) in the State of Victoria, Australia. We examined the relationship between temperatures and mortality using quasi-Poisson regression and the distributed lag non-linear model (dlnm) and compared the temperature-mortality association between the two periods: period 1- prior-HARS (1992-2009) and period 2- post-HARS (2010-2019). Since the HARS heavily weights heatwave effects, we also compared the main effects of heatwave events between the two periods. The heatwaves were defined for three levels, including 3 consecutive days at 97th, 98th, and 99th percentiles. We also controlled the potential confounding effect of seasonality by including a natural cubic B-spline of the day of the year with equally spaced knots and 8 degrees of freedom per year. The exposure-response curve reveals the temperature mortality was reduced in period 2 in comparison with period 1. The relative risk ratios (RRR) of Period 2 over Period 1 were all less than one and gradually decreased from 0.86 (95% CI, 0.72-1.03) to 0.64 (95% CI, 0.33-1.22), and the differences in attributable risk percent increased from 13.2 to 25.3%. The reduction in the risk of heatwave-related deaths decreased by 3.4% (RRp1 1.068, 95% CI, 1.024-1.112 versus RRp2 1.034, 95% CI, 0.986-1.082) and 10% (RRp1 1.16, 95% CI, 1.10-1.22 versus RRp2 1.06, 95% CI, 1.002-1.119) for all groups of people. The study indicated a decrease in heat-related mortality following the operation of HARS in Victoria under extreme heat and high-intensity heatwaves conditions. Further studies could investigate the extent of changes in mortality among populations of differing socio-economic groups during the operation of the heat-health alert system.

Envisioning environmental equity: climate change, health, and racial justice

Climate change has a broad range of health impacts and tackling climate change could be the greatest opportunity for improving global health this century. Yet conversations on climate change and health are often incomplete, giving little attention to structural discrimination and the need for racial justice. Racism kills, and climate change kills. Together, racism and climate change interact and have disproportionate effects on the lives of minoritised people both within countries and between the Global North and the Global South. This paper has three main aims. First, to survey the literature on the unequal health impacts of climate change due to racism, xenophobia, and discrimination through a scoping review. We found that racially minoritised groups, migrants, and Indigenous communities face a disproportionate burden of illness and mortality due to climate change in different contexts. Second, this paper aims to highlight inequalities in responsibility for climate change and the effects thereof. A geographical visualisation of responsibility for climate change and projected mortality and disease risk attributable to climate change per 100 000 people in 2050 was conducted. These maps visualise the disproportionate burden of illness and mortality due to climate change faced by the Global South. Our third aim is to highlight the pathways through which climate change, discrimination, and health interact in most affected areas. Case studies, testimony, and policy analysis drawn from multidisciplinary perspectives are presented throughout the paper to elucidate these pathways. The health community must urgently examine and repair the structural discrimination that drives the unequal impacts of climate change to achieve rapid and equitable action.

Vulnerability of Australia to heatwaves: A systematic review on influencing factors, impacts, and mitigation options

BACKGROUND

Heatwaves have received major attention globally due to their detrimental effects on human health and the environment. The frequency, duration, and severity of heatwaves have increased recently due to changes in climatic conditions, anthropogenic forcing, and rapid urbanization. Australia is highly vulnerable to this hazard. Although there have been an increasing number of studies conducted in Australia related to the heatwave phenomena, a systematic review of heatwave vulnerability has rarely been reported in the literature.

OBJECTIVES

This study aims to provide a systematic and overarching review of the different components of heatwave vulnerability (e.g., exposure, sensitivity, and adaptive capacity) in Australia.

METHODS

A systematic review was conducted using the PRISMA protocol. Peer-reviewed English language articles published between January 2000 and December 2021 were selected using a combination of search keywords in Web of Science, Scopus, and PubMed. Articles were critically analyzed based on three specific heatwave vulnerability components: exposure, sensitivity, and adaptive capacity.

RESULTS AND DISCUSSION

A total of 107 articles meeting all search criteria were chosen. Although there has been an increasing trend of heat-related studies in Australia, most of these studies have concentrated on exposure and adaptive capacity components. Evidence suggests that the frequency, severity, and duration of heatwaves in Australian cities has been increasing, and that this is likely to continue under current climate change scenarios. This study noted that heatwave vulnerability is associated with geographical and climatic factors, space, time, socioeconomic and demographic factors, as well as the physiological condition of people. Various heat mitigation and adaptation measures implemented around the globe have proven to be efficient in reducing the impacts of heatwaves.

CONCLUSION

This study provides increased clarity regarding the various drivers of heatwave vulnerability in Australia. Such knowledge is crucial in informing extreme heat adaptation and mitigation planning.

Heat Adaptive Capacity: What Causes the Differences Between Residents of Xiamen Island and Other Areas?

Extreme heat events caused by climate change have serious adverse effects on residents' health in many coastal metropolises in southeast China. Adaptive capacity (AC) is crucial to reduce heat vulnerability in the human-environment system. However, it is unclear whether changes in individual characteristics and socioeconomic conditions likely amplify or attenuate the impacts of residents' heat adaptive capacity (HAC) changes. Moreover, which public policies can be implemented by the authorities to improve the HAC of vulnerable groups remains unknown. We conducted a questionnaire survey of 630 residents of Xiamen, a typical coastal metropolis, in 2018. The effects of individual and household characteristics, and government actions on the residents' HAC were examined by using ordinal logistic regression analysis. Results show that the majority (48.10%) of Xiamen residents had a "medium" HAC level, followed by a "high" level (37.14%). On Xiamen Island, residents who settled locally for one-three years and spent less than one hour outdoors might report weaker HAC, and their HAC would not improve with increased air conditioning units in household. In other areas of Xiamen, residents with more rooms in their households, no educational experience, and building areas <50 m2 might report better HAC. Further, vulnerable groups, such as local residents and outdoor workers on Xiamen Island, people lacking educational experience and renters in other areas of Xiamen, showed better AC to hot weather than those in previous studies. Low-income groups should be given more attention by local governments and community groups as monthly household income played a positive role in improving Xiamen residents' HAC. Rational green spaces planning and cooling services, such as street sprinkling operations, provided by municipal departments can effectively bring benefits to Xiamen residents. Identification of basic conditions of AC has significant implications for practical promoting targeted measures or policies to reduce health damages and livelihood losses of urban residents during extreme heat events.

Vulnerability to heatwaves and implications for public health interventions - A scoping review

BACKGROUND

Heatwaves form a serious public health threat, especially for vulnerable groups. Interventions such as active outreach programs, exposure reduction measures and monitoring and mapping of at-risk groups are increasingly implemented across the world but little is known about their effect.

OBJECTIVES

To assess how vulnerable groups are identified and reached in heat health interventions, to understand the effectiveness and efficiency of those interventions, and to identify research gaps in existing literature.

METHODS

We performed a literature search in relevant scientific literature databases and searched with a four element search model for articles published from 1995 onward. We extracted data on intervention measures, target group and evaluation of effectiveness and efficiency.

RESULTS

We identified 23 eligible studies. Patterns exist in type of interventions 1) to detect and 2) to influence extrinsic and intrinsic risk and protective factors. Results showed several intervention barriers related to the variety and intersection of these factors, as well as the self-perception of vulnerable groups, and misconceptions and unfavorable attitudes towards intervention benefits. While modest indications for the evidence on the effectiveness of interventions were found, efficiency remains unclear.

DISCUSSION

Interventions entailed logical combinations of measures, subsumed as packages. Evidence for effective and efficient intervention is limited by the difficulty to determine effects and because single measures are mutually dependent. Interventions prioritized promoting behavioral change and were based on behavioral assumptions that remain untested and mechanisms not worked out explicitly.

CONCLUSIONS

Multifaceted efforts are needed to tailor interventions, compiled in heat health warning systems and action plans for exposure reduction and protection of vulnerable populations, to fit the social, economic and geographical context. Besides adequately addressing relevant risk and protective factors, the challenge is to integrate perspectives of vulnerable groups. Future research should focus on intervention barriers and improving the methods of effectiveness and efficiency evaluation.