In the Hot Seat with Dr. Kelly Turner

Shade our cities: the most impactful way to improve how people experience heat

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We are excited to re-introduce our long-standing interview series, In the Hot Seat.

Over the summer we have met with renowned academics and industry experts from London to LA to get their insights into how climate research and our understanding of extreme heat is changing as the climate crisis continues.

For the first interview of the year, and our first international In the Hot Seat, we caught up with Dr. Kelly Turner: Associate Professor of Urban Planning and Geography at UCLA and the Director of the Luskin Center for Innovation’s Center for Heat Resilient Communities.

From overheating in schools to the power of shade, she shared insights on the practical solutions communities can use to adapt to rising temperatures.

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Our Hot Takes from the interview with Dr. Turner

• Heat resilience should be about helping people thrive, not just survive. Too often, heat adaptation is judged by preventing deaths alone. We should instead be designing communities where people can continue learning, working, exercising and enjoying everyday life despite rising temperatures.
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• Shade may be one of the most powerful and overlooked climate adaptation tools. Whether provided by trees, buildings or canopies, shade directly reduces how hot people feel, making outdoor spaces far more usable and improving quality of life during hot weather.
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• Schools deserve to be at the centre of heat adaptation. Children spend much of their week at school, yet the impacts of heat on learning, behaviour and wellbeing are still underestimated. Investing in cooler schools has the potential to deliver lifelong benefits.
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• Better governance is just as important as better design. Heat cuts across planning, public health, education and infrastructure, but responsibility is often fragmented. Cities need clearer leadership, stronger coordination and sustained funding to deliver meaningful change.
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• We need to measure what people actually experience. Traditional metrics such as surface temperature only tell part of the story. Designing truly heat-resilient places means focusing on thermal comfort and how people move, work and live within cities, rather than relying solely on satellite data or abstract temperature readings.

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Thank you for joining us, Kelly. To start, could you tell us a little about your background and what led you to focus on extreme heat?

Yeah, sure. Thank you so much for having me. I'm really excited to be speaking with you. I’m currently a Professor of Urban Planning at UCLA and I also direct something called the Luskin Center for Innovation's Extreme Heat Equity Research Group. These two roles are closely connected because I have one foot in academic research and the other in a centre focused on environmental planning and policy. As a result, a lot of my work involves translating research into practice.

But how did I come to study heat? Well, my PhD was in geography. I was working with a lot of remote sensors and I started getting really interested in what makes a city sustainable or not. A lot of folks were using remote sensing and satellite imagery to assess that, and one of the variables available to people who use those methods is surface temperature and albedo, the reflectivity of surfaces, and vegetative cover. As I started interacting more with actual planning practitioners, I was realising that those tools are really limited in a lot of ways, because what they're measuring is an estimate of the surface skin temperature of the earth. And that's not how people feel and experience and move through environments. And it's only this small sliver of what it means to be hot. So, that's how I really got interested in this problem because it seems like the world's only getting hotter. We need to design solutions. And there seems to be a gap between those most capable of assessing the situation and those who were trying to find solutions.

We've been inspired by your work on overheating in schools. Why are schools such an important focus for heat adaptation?

So, this goes to the core of the narrative around how we're talking about heat. First of all, I have to step back and say, I'm really just excited that it's getting the attention it deserves now. But when we think about heat in the media and the narratives, it's really mostly around extreme heat. And that's actually borne out in content analysis we do of media and documents. The term ‘extreme heat’ comes up a lot. But extreme heat orients our attention in a certain way. It orients us around, well, when it's too hot, that means we don't survive, we die. And so, we start looking at mortality and morbidity data at population scales, and certain populations will pop out. For instance, elderly or outdoor workers. And that is something that definitely needs to be addressed. However, there is a blind spot in that way of framing heat. And if we start to talk about things such as well-being and quality of life, then we can start to focus our attention on other groups and other problems.

If we think about children within this problem, we don't see lots and lots of children overheating and dying, although it does happen in extreme cases. But what we see are things like degraded learning outcomes, behavioural issues, and even things like preterm births that can affect things like concentration and stuff that are downstream. These can be life-course-disrupting factors with children. The other thing that's really interesting about children is that, by the time they're five or six, they become physiologically capable of withstanding heat, kind of like an adult. However, psychologically, they don't. They don't have fully-formed brains. So, when they are overheating, they don't really get that signal. So, there's a lot of nuance there.

So, that's why it's important, but it's also important because schools are where they spend a lot of time. They can spend sometimes up to 60 hours a week, depending on aftercare situations or afterschool sports or weekend activities. In LA at least, schools are the largest public land holders. And so, there's this gigantic opportunity to bring a huge benefit to a population that can receive lifelong benefits from intervention for a really large portion of their day.

Yeah, I think that's really important. What might be some of the interventions to adapt schools for extreme heat?

We tend to think about interventions in two buckets. One is physical adaptations, and then the other is the systematic changes, the governance and regulatory changes that we can make. And with both of those, we can then further break this down into the benefit to the individual human's health. And then we can think about how many people it services.

Our research group is currently writing are port for the State of California, assessing some of their programs around heat. When you have to assess something as different as, for example, cool roofs to surveillance systems for heat, you need a framework to deal with that. And so, it is theoretically possible to have, on one hand, a physical intervention that really, really helps one person, but isn't democratically accessible to everyone. Like one person installing air conditioning in their home. Or you could have something like an urban greening program that will bring benefits to anyone via public space, but maybe the translation to an individual body is relatively minor. And the same with more social interventions. So, we definitely need a mix of them.

Shade is really illustrative of this. So, when we think about physical interventions, I think we need to be focusing on those that are what I call, quote unquote, metabolically significant. So, what that means is the cooling is sufficient enough that a person can gain activity level. So, for instance, if it is a sunny day, it is 95°F [35°C], it is 40 percent humidity, a healthy adult can walk in the sun, run in the shade, and an elderly person could only be sedentary. Notice in that example, the shade is pulling that adult from being able just to walk to being able to run. And that might seem minor but, from a quality of life standpoint, that means you're able to do more things that you normally need to do in your daily life. If you're a runner like me, you want to have shade so you can continue your run. But it also translates to people who are doing outdoor lab or, who might need to consider, if they should adjust their working day, working until 10 o’clock in the morning and then again after 4 or 5pm.

And that starts to bridge into governance and policy. So, once we know with a finer scalpel, how these physical benefits translate into activities in different places and locations, we can start to think about how we can adjust the knob on government to make those a reality.

What are the main ways that shade interventions can be used in a city and how might shading affect how people experience heat?

Shade is really important because when you are in a city, the thing that makes you feel hot or not is how much sunlight is hitting your body. So, when you're outside, it may be a certain temperature across the city, but there is some local variation. And the way that people experience that variation is from solar exposure. And we all kind of know this intuitively. You've probably been outside when it's hot and stepped under tree or an awning and experienced just how much it helps to cool us off. That's because we feel heat from many different sources. We feel the air temperature, the humidity, the wind, ventilation, and we feel it from radiant heat from the sun, the sun's energy. And that hits us directly and it hits surfaces around us and re-radiates back at us.

You can think about shade as a form of prevention. If you stop the sun from hitting your body, you stop your body from heating up. Likewise, if you prevent the sun from heating a surface, you reduce the amount of heat that is radiated back onto people. There are other interventions that can help, but they are generally not as effective. For instance, we like to vilify asphalt. There's a lot of problems with asphalt, but someone standing in full sun on grass is unlikely to feel meaningfully cooler than someone standing on asphalt. If you're exposed to direct sunlight, you'll still feel really hot.

To get to your second point - how do we experience shade in cities? - I think most people would say trees, and that's absolutely true. But shade can be cast by anything that's vertical: a building, a wall, an awning. Cities need to think about shade as infrastructure considering all the green and grey elements that can cast shadows and help create cooler, more resilient environments.

And I would say even broader infrastructure includes the governance systems these interventions - but sticking with the physical elements we've invested a lot of time into trying to better understand what shade do we need and how much is enough? These are the questions we are asked the most often.

Following up on this governance element: As extreme heat adaptation requires the involvement of many different stakeholders, how do you think we can work together across the public, private, and third sectors to create a more coordinated approach to heat adaptation?

That’s a really fantastic question. And I think the honest answer is that we actually don't yet know the most effective way to do that, because heat doesn't have one clear home. There are a lot of experiments happening in government design right now. Do we need a chief heat officer or some sort of central agency to be like a coordinating body in perpetuity or at least in an interim way to get the right people at the table together? Do we need to do coordinating committees or forums to get people talking to each other? The problem is that without dedicated budgets or resources, we risk asking city officials to take on two jobs with the capacity of one.  

And the central question that we need to ask is: why do some cities develop this thermally intelligent set of institutions that are can make their cities heat resilient in the future and why do some struggle to do that? It might be something as basic as they have experienced a major shock in the past that prompted a change. Or, in the case of many older cities around the world, especially those in Europe, they may be drawing on centuries of adaptation shaped by living in hot climates before the era of air conditioning or maybe it is these more kind of purposeful process of learning and institutional change.

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When we look at examples of coordinated action on heat in the US, where do we see the best examples of this working?

Yeah, I think there's some really interesting experiments happening on the West Coast which is where I’m most familiar with the work. Arizona, California, and Washington all come to mind, particularly because of action being taken at the state level.

I think this speaks to the challenge that different aspects of becoming heat resilient are embedded within different levels of government in the US. For example, infrastructure questions sit largely within local government, involving actors like Department of Public Works or even private sector developers. County-level public health may be responsible for heat surveillance, while state governments have the ability to pass broader rights and protections.  

In Arizona and Pheonix for example, they have both the Chief Heat Officer operating at the state level and in Phoenix. In California, the Governor's Office of Land Use and Climate Innovation has also established a group that is coordinating heat action at the state level. But I think what is particularly interesting is the links to local governments are even more explicit in that instance because there is a direct funding pipeline between state programs and local communities.

But I think I would just leave with one final question: fundamentally, what does it mean to be too hot? Does it mean creating conditions where people are surviving and not dying? Or does it mean creating liveable communities and enabling people to continue to have a high quality of life, even though our conditions are hotter than normal.

That's a really impactful question, is it enough to simply survive or can we create communities that are resilient and able to thrive despite this challenge?

I think there’s a sort of a sandwich in the middle. Some of my colleagues who are working in thermo-physiology and heat health impacts talk about the difference between survival and liveability. There is a huge gap between somebody getting really ill and dying from heat, and someone being able to continue living their daily life safely and comfortably. There's a lot of different ways that your life can be disrupted by heat. And I think we don't particularly always think about if you have a kid and you need to take them to soccer practice and that soccer practice happens at 5 pm, and it's 90°F [32°C]. What do you do if it's hot? Do you cancel the whole first month of practice or do you think about having flexible schedules? Is artificial turf really the best thing to be putting out there or will it just amplify the effect of heat? That’s just one example, but our everyday way of life is being challenged by this slow-moving needle and gradual shift in climate. We need to start paying attention to these smaller disruptions because once they accumulate, they begin to impede quality of life in much more meaningful ways.

Thank you so much, Kelly, for joining us today. It was really amazing to
hear your insights and to talk through a lot of the issues around heat.

It was a really amazing opportunity.

Yeah, thank you for the thoughtful questions and for elevating the topic.

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Further Reading

- Turner, V. K., Rogers, M. L., Zhang, Y., Middel,A., Schneider, F. A., Ocón, J. P., … Dialesandro, J. (2022). More than surfacetemperature: mitigating thermal exposure in hyper-local land system. Journal ofLand Use Science, 17(1), 79–99. https://doi.org/10.1080/1747423X.2021.2015003

- Turner, V. K., French, E. M., Dialesandro, J.,Middel, A., Hondula, D. M., Ban Weiss, G., & Abdellati, H. (2022). How arecities planning for heat? Analysis of United States municipal plans.Environmental Research Letters, 17(6), Article 064054. DOI:10.1088/1748-9326/ac73a9

- Turner, V. K., Middel, A., & Vanos, J. K.(2023). Shade is an essential solution for hotter cities. Nature, 619,694-697. https://doi.org/10.1038/d41586-023-02311-3

School Guidance

Funding school heat management

Changing behavior on hot school days

Cooling classrooms to healthy temperatures

Protecting students from heat outdoors

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