Solving the crisis: Rising urban temperatures

The "Solving the crisis:" series explores the pressing challenges of our time, including climate change, biodiversity collapse, housing affordability and more. Each article highlights how Waterloo, a hub of research, innovation and creative thinking, is uniquely positioned to address these issues. Through this series, we highlight the dedicated researchers who are tackling global crises and shaping a better future for all.

The University of Waterloo is a leader in sustainability research and education. Home to the largest Faculty of Environment in Canada, Waterloo has been a catalyst for environmental innovation, solutions and talent for 50 years.

Dr. Peter Crank at a press conference in Hong Kong talking about extreme heat

Crank’s vision provides a comprehensive roadmap for cities and society to navigate the complexities of climate change effectively.

Nature-based solutions for urban heat

“Nature-based solutions, like increasing vegetation and tree canopies, are crucial in urban settings for cooling,” Crank explains. “It's essential to tailor these solutions to local climates, as what's effective in one region may not work in another. Additionally, engineered shade structures, such as bus stop shelters and fabric shade sails, also play a significant role in mitigating heat impacts.”

Particularly in urban settings where concrete and asphalt exacerbate heat, increasing urban vegetation and expanding tree canopies, which provide natural cooling and improve air quality.

“In cities like Waterloo and throughout eastern Canada, planting large, shade-providing trees such as oaks and maples can significantly reduce urban temperatures,” Crank says. “However, a solution must be tailored to local climates. In arid regions like Phoenix, Arizona, native or drought-resistant plants and engineered shade solutions are often more appropriate.”

This localized approach ensures that vegetation thrives and effectively mitigates heat without exacerbating other challenges like water shortages.

Green roofs are another solution for some cities. These roofs, which support layers of soil and vegetation, not only cool buildings but also enhance biodiversity and improve urban air quality. While taller buildings may not directly cool street-level temperatures, they reduce overall energy consumption and heat emissions, indirectly benefiting pedestrians down below.

Incentivizing climate-friendly practices

Implementing nature-based solutions requires more than just planting trees or installing green roofs — it requires robust incentivization strategies. Policies that encourage individuals, businesses and governments to adopt climate-friendly practices are essential.

“In Toronto, a green roof incentivization program has led to a notable increase in green roofs, particularly in densely populated areas,” Crank explains. “Similarly, the Region of Waterloo is considering regulations to ensure rental units maintain safe indoor temperatures during heatwaves. These policies, if implemented, can protect residents from extreme heat and promote energy efficiency.”

Crank also discusses the potential of incentivizing lighter-coloured roofs, which reflect more sunlight and reduce building temperatures. Such initiatives can be simple yet effective, especially if supported by local governments and homeowner associations. By providing tax breaks, subsidies or other financial incentives — cities can accelerate the adoption of these solutions.

“Cities need to revisit zoning codes to facilitate tree planting and ensuring the maintenance of public vegetation,” Crank underscores. “Municipalities might offer rebates for residents who plant and maintain trees or take on the responsibility of watering and caring for public trees themselves.”

Communicating science and building trust

Effective climate action hinges not only on robust solutions but also on public trust and understanding. Crank emphasizes the critical role of transparent and clear science communication. In an era where misinformation is rampant, building trust in scientific research is paramount.

“As scientists, we need to contextualize our data in ways that resonate with the public,” Crank says. “Instead of presenting abstract figures, we should frame the benefits of climate solutions in tangible terms. Explaining how green roofs can lower monthly energy bills or how urban trees lead to reduced hospital admissions due to heat-related illnesses makes the science more relatable and compelling.”

He also stresses the importance of engaging with communities to address their specific concerns and needs.

“Addressing climate change is an all-of-society problem, with every decision — whether it's planting trees or installing green roofs — having unintended consequences,” Crank says. “We must consider these impacts from the outset and collaborate with the community to understand their concerns.”

When implementing solutions like planting trees, issues such as maintenance and neighbourhood safety need to be considered. Similarly, while cooling centres provide relief for those without air conditioning, they can often feel unwelcoming and even dehumanizing. Therefore, it is important to think beyond mere functionality and create spaces that also foster community and reduce social isolation.

“But with all of this, it requires not just knowing the science, but knowing the people,” Crank reinforces. “Success depends on community-based partners, cross-disciplinary conversations and approaching these efforts with empathy and flexibility.”

Crank's ideas for addressing the climate crisis is rooted in practical, localized solutions that leverage the power of nature. By incentivizing climate-friendly practices and enhancing public trust in science, his approach offers a holistic framework for urban resilience. As cities worldwide confront the growing threats of climate change, these insights provide a valuable guide for creating sustainable and livable urban environments for all.

Illustrations generated by Midjourney