How to cool communities in the face of rising heat

With heatwaves hitting Canada harder and more often, there’s an urgent need to rethink how we design homes and neighbourhoods.

We spoke with three UBC experts: Dr. Rachel H. White (RHW), an atmospheric sciences professor studying the influence of climate change on extreme weather; Dr. Lorien Nesbitt (LN), a faculty of forestry professor focused on urban forestry and environmental justice; and Dr. Sara Barron (SB), program director of UBC’s Master of Urban Forestry Leadership.

Together, they explain how smarter design and nature-based solutions can keep Canadians cool, safe and healthy.

How much can trees and green spaces cool down cities?

LN: Even a 1-2 C drop can significantly reduce heatwave health risks, and urban trees and green spaces do this by shading surfaces and reducing mean radiant temperatures by 4-5 C or more. Urban vegetation is a game changer. It’s essential for heat resilience, especially in high-risk areas, and it improves air quality and biodiversity year-round.

What’s the best way to design homes and neighbourhoods to stay cool during heatwaves?

SB: Combine strategies: low-energy home cooling, accessible public cool spaces, drinking water, public washrooms and plenty of overhead shade. Tree shade, in particular, is low-cost and high-impact, cooling neighbourhoods and reducing building energy use when planted strategically. Our recent study shows that when urban forests are planned for health, resilience and diversity, they deliver even greater benefits like cooling, biodiversity and equity as cities grow.

LN: Design for how people use space. Shade should cover busy walkways and gathering spots. Cooling features like trees or shaded seating should be where people actually are, not just where they look good on a plan. Vulnerable people must be able to access these features, and greenspace in general.

How should natural climate variability factor into planning for heat resilience alongside climate change?

RHW: Natural variation in weather and climate (or “chance”) plays a big role in whether a region experiences a heatwave in any given year. The 2021 Pacific Northwest heatwave was a mix of bad luck and human-caused climate change. Just because a region hasn’t seen a record-breaking extreme heat event in recent years doesn’t mean it won’t this year. Cities must prepare for record-breaking events before they happen, as climate change is making extreme heat more likely everywhere.

What’s holding cities back from tackling extreme heat?

SB: A lack of resources for neighbourhood-level planning and policy. Cities have many priorities, and impactful local solutions take time and money. Meanwhile, densification is happening without protecting mature trees. That worries me—are we leaving enough shade for people?

LN: Another gap is that heat response often falls between jurisdictions: public health, planning, emergency management. Many cities lack heat strategies, risk data or funding mechanisms for long-term solutions. And planning often misses how people experience heat—overlooking equity and real-world needs. This requires collaboration, community engagement and sustained investment.

How do we make sure heat resilience benefits the most vulnerable?

SB: Start by asking people what they need. What stops them from accessing cool spots? Are those spaces welcoming? Can they get there on a shaded path? Past heatwaves show the most vulnerable suffer the most. We should build resilience with them, not just for them.

LN: And support what’s already working—mutual aid, community care, informal cooling strategies. Cities shouldn’t impose top-down fixes. Partner with community leaders to co-create local solutions. Invest in both public and social infrastructure: cooling centres, affordable housing, shade and networks of care that help people cope. That’s the focus of our new project that is co-developing equitable, community-led nature-based solutions that address climate vulnerability and environmental justice in Vancouver.