Pedestrians in Times Square in New York City during a July 2022 heat wave.

Pedestrians in Times Square in New York City during a July 2022 heat wave. Spencer Platt / Getty Images


What Will It Take to Save Our Cities from a Scorching Future?

The U.N. named Eleni Myrivili its first-ever global chief heat officer based on her record as a city official in Athens. In an e360 interview, she talks about why extreme heat is a health crisis and what cities must do to protect the most vulnerable from rising temperatures.

In 2022, a year in which 70,000 Europeans died of heat-related causes, the United Nations named Eleni “Lenio” Myrivili the world’s first-ever global chief heat officer. A former deputy mayor of her hometown of Athens, Greece, Myrivili had overseen a multimillion-dollar budget and a staff of 500 and was largely responsible for establishing that city’s reputation as a leader in climate-change adaptation.

Now, she is working to expand that vision on a global scale. Her track record of making change through collaborations with national governments, U.N. agencies, NGOs, foundations, academia, and the private sector led the journal Nature to name Myrivili one of 10 people most responsible for shaping science in 2023.

Of particular concern to Myrivili is the impact that extreme urban heat — the number-one public health issue cities will face in the coming decades — will have on the world’s most vulnerable. In an interview with Yale Environment 360, she stressed the need to protect these populations, in part by ensuring that more financing flows in their direction. “Cities that have money can show us the way, and then others can see what fits and what doesn’t,” she says. “But we have to focus on the poorer cities, which are the ones that will suffer most.”

Eleni Myrivili

Eleni Myrivili Eleni Myrivili

Yale Environment 360: What does the position of Global Chief Heat Officer entail?

Eleni Myrivili: I’m folding work on heat resilience into the initiatives that UN-Habitat [the United Nations’ program for human settlements and sustainable urban development] is doing in urban centers. They’ve been working on sustainability, accessibility, equity, and how to make cities more livable, especially in the Global South, but climate change hasn’t really been central. My aim is to elevate heat as an issue because it affects lives and livelihoods more than any other climate consideration.

e360: People seem to be aware of the dangers of floods and wildfires, but heat has somehow flown under the radar. Is that changing?

Myrivili: Very much so. Last year was the hottest year ever recorded. We had endless fires and heatwaves. People in the Northern Hemisphere were swimming in months that they’d never gone swimming. We are suddenly becoming much more conscious about heat and how it’s linked with events like drought, wildfires, flooding, hurricanes, and tornadoes.

“We’ve built cities based on the idea that we have fossil fuels to help us deal when it gets too hot.”

e360: A recent study published in The Lancet Regional Health - Europe found that in the summer of 2022, extreme heat killed 70,000 people in Europe. Is quantifying the impact of extreme heat something that people have begun to focus on more?

Myrivili: The proliferation of studies linked to heat in the last few years is amazing. Studies on everything from meteorological impacts to impacts on the body.

e360: How does extreme heat affect the body?

Myrivili: The main way our body deals with heat is through perspiration. But if there’s a lot of humidity in the air, perspiration doesn’t evaporate and cool us down. Our body goes into a panic. The cardiovascular system is affected first, as it tries to move blood to the skin and to our muscles. But then a whole series of systems starts to have trouble. You can become dizzy or confused because not enough blood goes to the head, or you can go into renal failure. This is why heat can send people with pre-existing health problems to the hospital really fast.

A pocket park in Athens.

A pocket park in Athens. Athens Municipality

e360: Heat is a particular problem in cities, where two-thirds of the global population will live by 2050. Why is it so problematic in urban areas? What happens in a city that doesn’t happen in the countryside?

Myrivili: The problem with cities is that we have a built environment based on concrete, asphalt, glass, and steel. These materials all absorb heat and radiate it at night. If night temperatures don’t fall — in the Northern Hemisphere, at least — your body never really recovers from the daytime heat. It’s the night temperatures, rather than the morning temperatures, that are the dangerous time. That is why, when we talk about creating shade in streets or in public spaces, we want shading that is retractable, so the heat is not trapped in the city at night.

We’ve also built cities based on the idea that we have fossil fuels to help us deal when it gets too hot or too cold. We forgot that for centuries people found solutions for extreme environments, and we threw them out the window. We had internal courtyards with water fountains and trees. We had double roofing with air passing through and whitewashing, which reflects the sun’s rays. This is a particularly important solution in poor countries, where the roofs tend to be concrete or corrugated iron.

e360: What have you been doing to cool things down in Athens?

Myrivili: We’ve been adding trees and green spaces, which, in a densely built city like Athens can be difficult. We’ve done pocket parks and created new spaces by moving and demolishing buildings, but also by putting green corridors in existing streets and taking away cars. Cars and air conditioners create more heat in public spaces. We need to create green streets, green corridors for pedestrians, electric public mobility, scooters, and bicycles. The centers of the cities of the future should be empty of cars. In places like Amsterdam and Paris, they’re already doing this.

“There’s evidence that when heat waves are named, there’s a different type of mobilization.”

We’re also taking advantage of the engineering feat that is a 24-kilometer-long underground aqueduct built by the Romans in 150 A.D. There’s still water in there, clean enough to use for irrigation, so the Athens Water Supply and Sewerage Company, which owns the aqueduct, is working with the Ministry of Culture — because it’s a monument — and the eight municipalities under which it runs to produce a strategic plan that will create green spaces supported by the aqueduct that will be built to specific guidelines to ensure they cool the city.

e360: If you have to knock down buildings and create new roads and new parks, you’re going to need buy-in from many different entities, each with their own interests. How much of your work is coming up with innovations and working with scientists and landscape designers, and how much is just trying to get the politics ironed out, to get everybody on board to make what, in many cases, are very big changes?

Myrivili: This is why the chief heat officer role is important. Because you have to have somebody who is doing all the politicking and who is willing to knock on doors and get different people to collaborate. It takes a long time, and it’s not easy. The U.N. is an enormous administration, so it can be difficult to navigate.

A woman shields herself from the sun as she passes a mural in Beijing in July 2015.

A woman shields herself from the sun as she passes a mural in Beijing in July 2015. Andy Wong / AP Photo

e360: You have a master’s degree in performance studies and a Ph.D. in anthropology. Is this where those studies come in?

Myrivili: I wanted to be a theater director. I never thought I would enjoy being an administrative director, but I really loved it. When I was deputy mayor, we had 500 people in the department, and I enjoyed putting in place a team that worked well together. Anthropology has to do with being able to understand different perspectives and see that communities have different needs and references and ways of talking about things. Anthropology has helped me not to be a tourist, to be more part of the community wherever I go.

e360: You’ve talked about naming impending heat waves, the way we do with tropical storms and hurricanes.

Myrivili: There’s evidence that when heat waves are named, there’s a different type of mobilization. But more important than naming is categorization. This would be based on a system at the city level. You have to have a sense of when it becomes really dangerous and risky where you are.

“In the last few years, the number of people buying air conditioners has grown exponentially.”

But there are solutions that can help protect the most vulnerable. Labor ministries can enact laws that protect laborers, making sure that people working under dangerous conditions — particularly in lower-paying jobs like construction, agriculture, and delivery services — aren’t left to burn under the sun. When can people work, and under what conditions? When should they not work at all? How can we make sure we check in on people, especially older people living alone? We can create neighborhood networks with volunteer services and introduce apps that remind relatives to check in on folks.

e360: We know what a difference political leadership can make, for good or ill. Considering all that’s going on geopolitically, how do we stay hopeful?

Myrivili: I see the private sector dealing with climate change more and more seriously, as companies realize that their systems are dependent on logistics, transportation systems, and natural resources that are coming under threat.

At the U.N. Climate Change Conference in Dubai, 63 national governments signed onto something called the Global Cooling Pledge, committing to reduce cooling-related emissions while increasing access to cooling. This is important because we have close to 2 billion units of air conditioning around the globe. In the last few years, the number of people buying air conditioners has grown exponentially, especially in countries with growing middle classes.

A green space atop a metro station in Singapore.

A green space atop a metro station in Singapore. David Goldman / AP Photo

e360: Singapore seems to be leading the way when it comes to heat management.

Myrivili: The city-state has done an amazing job creating basic rules through which we can understand how to create cooler districts, neighborhoods, streets, and buildings, from the big picture to the small. When establishing new neighborhoods, they consider how high the buildings should be, how deep the canyons, how to organize the shading that comes from the buildings. And Singapore’s great because it’s a city and a state, and it has money.

e360: But what about places like Dhaka and Lagos?

Myrivili: We have to mobilize financing and create policies that can help people in those cities. That’s why I wanted my position to be part of UN-Habitat, because that’s where the focus is.

e360: Are there financial mechanisms, through the World Bank or otherwise, specific to heat in cities?

Myrivili: This is part of my big effort within the U.N., to create a specific mechanism that can target financial support to cities around the world for saving people from losing their lives or livelihoods to heat.

We have to ramp up resilience and adaptation financing because we’ll save lives and ecosystems. Even though heat will be the number-one public health issue that cities will be dealing with in the coming decades, it’s still difficult to get funding. We’re not ready for it, just as we weren’t ready for Covid. And we have to get ready.

This interview was edited for length and clarity.