Resilience in a Warming Climate: Public Place-Making for Health and Well-Being in Hot Cities
Louise McKenzie and Susan Thompson
Place matters, as does the climate that largely determines how we use and interact with outdoor environments. Global warming is the most significant factor affecting the world’s climate. It is expected that the intensity, duration, and frequency of heat extremes will increase. In turn, the number of people at risk of adverse health outcomes is projected to rise. This will be exacerbated by continuing population growth, aging, and urbanization (WHO/WMO 2012).
The outcomes of a warming climate have direct and indirect consequences for human health. For Australia, heat-related deaths are projected to double over the forthcoming decade without strong mitigation (Hennessy 2011). Heatwaves, bush fires, thunderstorms, and floods are more likely as temperatures climb and these events will cause serious injury, illness, and death. Other problems will also arise which have implications for health. These range from anxiety and depression about climate change impacts, to economic insecurity, job losses, food insecurity, and failing infrastructure. As well, hotter neighborhoods mean that places where people seek health-promoting exercise, relaxation, and social connection will be increasingly unpleasant and, in some cases, unusable if they are not well designed to be cool and comfortable. In this warming scenario, ‘place-makers’ are defined broadly as built environment professionals responsible for every stage of the place-making process — planning, design, construction, planting, creative installations, and ongoing maintenance. Place-makers are also in the business of building resilience. This must be done in consultation with the community, so that the places in which people interact appropriately support everyday activities, especially those that support health.
Helping people to keep as healthy and well as possible in the face of a warming climate is also an important aspect of maintaining people’s resilience. Accordingly, building resilience needs to be part of 21st-century place-making. To ensure this demands an understanding of heat-vulnerability, the impacts on human health and well-being, and the best ways to support people to be resilient in a warming climate.
This chapter is broadly divided into three parts. The discussion is initially situated in an Australian context. It considers the importance of sociocultural elements and explains the notion of population heat-vulnerability. The second part focuses on the way that heat influences urban environments and human behavior, particularly health-supportive activity such as walking and social connection. The final section examines the creation of resilient places and looks at how public place-making can support people to live healthy lives in a warming climate. To enable this to occur, our heat-sensitive design principles for place-makers in the 21st century are presented.
Place-Making in a Warming Climate for Health and Well-Being
To what extent are warming climates and health implications considered in healthy city approaches? Strategies acknowledge the need for shade provision, but assign it varying degrees of importance. However, a deep understanding of heat’s influence on outdoor behavior and comfort is essential to supporting healthy activities. This is particularly so for those dependent on the everyday use of outdoor public spaces which assist in maintaining well-being, reducing key risk factors for chronic disease. Climate and thermal comfort are two of a myriad of factors influencing the way people use outdoor public spaces, yet few studies explore heat and behavior in real-life outdoor settings.
Streets, plazas, and parks are where we seek social connection with others, where we play games and enjoy physical activity, and where we enjoy shopping for fresh food in open-air markets. A hotter climate threatens these health-supportive behaviors (Kent and Thompson 2014) and increases our heat-vulnerability. In turn, this renders people more susceptible to chronic ill-health. The places we have long depended upon to build and sustain community will no longer be able to do so unless a very different approach to place-making is adopted. This chapter explores how this might be done. The focus is on the ways in which places can be made for people that provide resilience in the face of warming climates and increasing heat-vulnerability. We are interested in the many overlays and interconnections between healthy city approaches (Barton et al. 2015) and heat-sensitive design, not easily teased apart as simply ‘hot’ and ‘cool.’ Rather, the overlays and interconnections paint a deeper picture of place, showing how place-making in a warming climate can bring both health-supportive and heat-protective approaches together, creating community resilience into the 21st century.
The Sociocultural Context of Place and Heat-Vulnerability
Climate and weather have important cultural dimensions that must be considered in place-making. The term ‘weather’ refers to the atmospheric variables for a brief time, whereas ‘climate’ represents the atmospheric conditions for a longer period and generally denotes the normal or mean course of the weather (ABOM 2016). Australia’s climate varies significantly, spanning tropical monsoons, desert regions, savannah, alpine, and temperate zones (ABOM 2014). The ‘variation and unpredictability’ of the Australian weather was particularly problematic for the nation’s early European settlers, unfamiliar with such varied patterns (Rose 2005: 38). In contrast, Aboriginal understanding of the climate is much more nuanced, based on detailed local observations, ensuring responsiveness to variations. This alerts place-makers to the need to engage in cross-cultural conversations as central to their practice.
Lowe (2005) suggests that European settlers and their descendants — bent on taming this ‘bright and savage land’ — have never realistically engaged with the Australian climate, leading to an ambivalence toward heat. Sun and sea are embedded within the Australian national psyche which venerates the outdoor life in hot weather — sea, surf, and sand (Lowe 2005) — despite the country having the highest skin cancer rates in the world. On hot days, hundreds flock to the beach (Figure 25.1). Yet there are many who are absent — those who are elderly or incapacitated, and people who find everyday tasks too difficult due to the heat. Similarly, we do not see the queues of people exposed to the full sun, waiting for insufficient buses services, or walking great distances along unshaded streets to their parked cars. Migrants and tourists to Australia, particularly those from cooler countries, may lack awareness of local climate and adaptive behaviors, particularly in relation to soaring temperatures. Non-English-speaking people are recognized as among the most vulnerable to heat-related illness (Victorian Health Department 2011).
Figure 25.1 Sydney’s iconic Bondi Beach where those with good access to the Eastern Seaboard flock on hot summer days.
Source: Photograph by Susan Thompson.
Social and cultural dimensions play an important part in determining how societies respond to climate-related risks. Yet such dimensions are rarely incorporated, thereby undermining community resilience (Adger et al. 2011). Building resilience to a warming climate is likely to be most successful when communities themselves play a role in contextualizing vulnerability and assessing adaptive capacity at a local level (Rydin et al. 2012).
To create resilient places in this warming scenario, we need to understand the impact of heat on people living in cities. Heat-vulnerability incorporates not just heat exposure, but also health, financial, cultural, and physiological conditions associated with keeping cool (Farbotko and Waitt 2011). Vulnerable groups who are especially at risk include the elderly and children, those suffering chronic ill-health, socially isolated people, those of low socioeconomic status, and outdoor workers (WHO/WMO 2012). Figure 25.2 illustrates how vulnerability is influenced by the interconnections between exposure, sensitivity, and adaptive capacity. These vary according to physical climatic conditions, human physiological characteristics, and social, economic, and cultural factors. For example, a wealthy, elderly person living in an air-conditioned home in a well-treed suburb near the coast is less exposed and has greater capacity to cope with heat impacts compared to a welfare-dependent older person in a non-air-conditioned house situated in a suburb with little greening and far from cooling sea breezes.
Adaptation is increasingly viewed as a necessary means of addressing climate change impacts and will evolve as impacts arise (Hanna and Spickett 2011). Understanding vulnerabilities and adaptation strategies requires cross-disciplinary approaches. Saman et al. (2013: 1), for example, demonstrate that “a combined approach including behaviour change, dwelling modification and improved air conditioner selection can readily adapt Australian households to the impact of heat waves.”
Figure 25.2 Vulnerability and its components.
Source: Garnaut (2008: 125). Garnaut Climate Change Review: Final Report ©Commonwealth of Australia (2008).
Priorities for Reducing Heat-Vulnerability
For cities, three critically important adaptation priorities are identified for reducing heat-vulnerability. The first targets the incidence of chronic disease, acknowledging that this is likely to “have the greatest impact on reducing the negative health consequences of climate change” (Bambrick et al. 2011: S76). The second priority involves reducing urban heat through improved urban design, planning, and service provision. This includes actions such as creating accessible cool, green spaces by planting vegetation, erecting shading structures, and building amenities such as swimming pools, together with the provision of improved active transport facilities. The third priority focuses on the social nature of the city — enhancing community cohesion and functioning, and active social networks (Bambrick et al. 2011). All priorities require an understanding of how heat impacts city environments. This is explored in the next section.
Heat and Urban Environments
Urban heat is a major health challenge exacerbated by global warming. Cities modify their own climates through land-use change and waste heat emissions, which are calculated to play a more significant role in urban warming than greenhouse gas emissions. Stone (2012: 13) highlights that cities “do not cause heat waves — they amplify them.”
Cities are impacted by a phenomenon known as the ‘urban heat island effect.’ Urban heat islands are characterized by air and surface temperatures hotter than their rural surroundings. They form because “many common construction materials absorb and retain more of the sun’s heat that natural materials in less-developed rural areas” (Gartland 2011: 1).
The urban heat island is affected by variations in intensity both temporally and spatially. Intensity varies throughout the day and night. It is generally smallest just after sunrise and largest at night following sunset. As well, the magnitude and timing of intensity peaks vary due to the thermal storage and emissivity of materials, with dry soil and timber releasing heat more readily than concrete and stone. Wind and moisture influence heat islands; they have varying impacts dependent on the nature of building materials, especially their thermal conductivity and heat storage capacity, together with the placement of buildings which creates wind tunnels and breaks. Heat islands are strongest when the weather is calm and clear, and weakest during cloudy, windy conditions (Gartland 2011; Stone 2012).
The urban heat island is further complicated by the radiation balance. This incorporates incoming solar and reflected radiation, and atmospheric and surface radiation, all of which are complex in themselves. As Samuels et al. (2010: 6) note, “radiant absorption and emissivity are in constant flux in the designed environment.” Consequently, some characteristics contribute heat to the urban heat island, whereas others are cooling. Land surface cover is the foremost contributor to urban heat, with deforestation and urbanization significantly influencing urban climate, but not through a simple relationship. Urban heat islands are also exacerbated by a range of factors. These include urban forms and design, as well as the absence of vegetation, extensive use of impermeable surfaces, low solar reflectivity of materials, and increased air pollution (Gartland 2011).
Urban heat islands pose serious threats to urban populations. The elevated night-time temperatures characterizing heat islands present health concerns related to excess thermal load and heat stress. Nairn and Fawcett (2015: 229) explain that the ability to dissipate heat overnight after a very hot day “dictates the accumulating thermal load impacting vulnerable people.” Accumulating thermal loads may lead to heat-related mortality and morbidity. However, heat effects on morbidity associated with people’s ability to carry out everyday activities are under-reported.