Heat, health, and humidity in Australia's monsoon tropics: a critical review of the problematization of ‘heat’ in a changing climate

Abstract

Exposure to heat has killed more people in Australia than all other natural hazards combined. As the climate warms, temperatures are projected to rise substantially, increasing the impact of heat stress and heat illness nation-wide. The relation between heat and health is profoundly complex, however, and is understood differently across multiple sectors. This paper thus provides a critical review of how heat is currently measured and managed in Australia, highlighting how humidity, exposure, and exertion are key elements that are not consistently incorporated into 'problematizations' of heat. The presence or absence of these elements produces different spatial and temporal geographies of danger, as well as different governance practices. In particular, the invisibility of humidity as having a significant impact on heat and health shapes whether Australia's tropical monsoon zone is visible as a region at risk or not, and whether prolonged periods of seasonal heat are treated as dangerous. Similarly, different populations and practices become visible depending on whether the human body (its exposure, exertion, cooling, and hydration) is included in accounts of what constitutes 'heat.' As a result, the outdoor, manual workforce is visible as a population at risk in some accounts but not others. A brief review of key policy areas including housing, public health and work health and safety is presented to demonstrate how specific problematizations of heat are critical to the identification of, and response to, current and future climatic conditions. This has implications for how populations, places, and practices are constituted in the region.

Exploring Heat Stress Relief Measures among the Australian Labour Force

“…We would have expected that respondents from the cooler regions (e.g., Tasmania) would be less likely to be often heat stressed than those in hotter jurisdictions such as Queensland and the Northern Territory. Even when the locations where people lived were separated into the tropical parts of northern Australia, characterized by high temperatures throughout the year and high humidity during large parts of the year (wet season), and southern Australia, we could detect no significant difference in level of heat stress, contrary to expectations [ 40 ]. Only one control variable, self-reported health, had a significant ( p < 0.001) impact on respondents’ heat stress levels with those in better health less likely to say they were often or very often heat stressed than those in poorer health.…”

Characteristics and thermodynamics of Sahelian heatwaves analysed using various thermal indices

“…Most notably our findings agree with Guichard (2014), Oueslati et al (2017) and Sambou et al (2020) on the leading role of greenhouse effect of moisture during Sahelian nighttime heatwaves. It should be noted that this process is not specific to the Sahel but is also observed during nighttime heatwaves over other tropical regions (e.g Oppermann et al 2017;Chen et al 2019). Likewise, the shortwave radiation at the southernmost part of the Sahel accompanying daytime heatwaves corroborates the findings of (Oueslati et al 2017) and is also found to drive some heatwaves in midlatitude areas like Europe (e.g Lhotka et al 2018).…”

The tropical backyard: performing environmental difference

“…While the temperate zone follows a pattern of summer/autumn/winter/spring, the tropical Australian north follows a wet/dry seasonality, and Cairns has an average yearly rainfall of almost 2,000 mm that falls mainly between November and April. The rain differential in Cairns is 1:8 rather than 1:3 in more temperate areas, which encourages unique water management practices and produces a 'hydrological' seasonality with a distinctive kind of tropical 'heat' (Oppermann et al, 2017). Rain comes in heavy downpours during months that are also very hot (an average of 32°C).…”