Forks Estate: Experts explain why it is still so hot in Phoenix

What is the urban heat island effect and how does it affect Phoenix?

Have you been wondering why Phoenix doesn't seem to be cooling down? It's normal for Phoenix and its surrounding areas to experience high temperatures but Phoenix has now become affected by urban heat island effect. This is when a city does not cool down at night. It's predominately caused in cities when people use too much energy or when natural vegetation and landscape is cleared. In this Forks Estate episode, Cassandra Laubach spoke with three experts about how to define urban heat island effect, what causes it, and how can we combat it. Her guests include ASU School of Sustainability graduate and current instructor Brigitte Bavousett, Director of Environmental Research Initiatives at Arizona State University's Polytechnic campus Albert Brown, and the president of the Central Arizona Chapter of The Society for Conservation Biology Corinne Johnson. 


  Cassandra Laubach:

Hello my name is Cassandra Laubach and you’re listening to The Forks Estate. On this episode of The Forks Estate we will discuss the future of hot cities such as Phoenix. Phoenix is not just a hot city because we live in the desert, but it's a hot city because of the urban heat island effect. I spoke with three experts this week about what this effect is, what the implications are and how we can try and solve the problem before it's too late. I had the pleasure of speaking with Brigitte Bavousett about this topic. Brigitte is part of the School of Sustainability here at Arizona State University, and she earned her masters With the School of Sustainability in December of 2008. Brigitte could you please explain what an urban heat island is and why it's so important that we focus on this issue?

Brigitte Bavousett:

Okay so urban heat island is very challenging concern because as our cities are heating up, we are of course using more electricity and air conditioning. So to speak to Phoenix in particular, the population of Phoenix started to skyrocket once air conditioning units were popular. And as we built and our population increased so quickly we built it out and had to pave a lot of roads to connect so we became a city built with road infrastructure and not a focus on public transportation. We’ve just been pouring more and more asphalt and concrete and covering up natural vegetation with housing developments and businesses and roads. And as the sun crosses the sky every day, that concrete retains the heat collected and at night, our in nighttime temperatures are hotter. And that’s what urban heat island is. It's the fact that we don't cool off at night.

Cassandra Laubach:

I also had the pleasure of speaking with Al Brown. Al Brown is a senior lecturer with the environmental research management program. Can you please explain to us why or what the main reason is why we're dealing with urban heat islands, and what you think we can do to help change this? 

Al Brown:

The main reason is because of the concentration of asphalt, concrete, dark colored rooftops and a lack of natural vegetation that was there before the area was developed. The greater Phoenix metro area, for example, was a part of the lower Sonoran Desert ecosystem and right there in downtown Phoenix the Salt River used to flow year-round and it had dense groves of mesquite trees, sycamore and cottonwood trees all around it's banks. All those are now gone and replaced with rooftops, concrete, asphalt and the buildings all generate air conditioning, heat and boiler heat from heating water, so there is a constant, I guess, out pour or addition of extra heat that wasn’t naturally present before. 

Cassandra Laubach:

So this is a man-made problem then? 

Al Brown:

Yes.

Cassandra Laubach:

Do you think that we could fix it or do we get back to nature in order to fix the problem?

Al Brown:

It's impractical to consider of demolishing all of the buildings and roadways. That's obviously not feasible, but wherever there are opportunities to change the color of roofs, for example, or plant roof gardens, color our roofs with lighter paints and shingles or other roofing materials that reflect more of the sun's energy. And then also communities gardens, trees, more green spaces. So whenever there is an opportunity to tear down a whole city block of old buildings and rebuild then, that can be done in a more environmentally friendly way. 

Cassandra Laubach:

So then do you think that, that idea and those proposals are feasible or do you think people will not want to participate in that?

Al Brown: 

It's certainly a personal choice for people to decide what they wish to do with their own private property, but in terms of government owned spaces or common areas, cities can make their choice to revegetate things like medians and city parks and other development projects with native vegetation, low water use trees, those kinds of things. It's not expensive to do that, it saves water, and it adds more of a reflective, less heat absorbing, type of surface. 

Cassandra Laubach:

What would you say to someone who says that they don't believe that urban heat islands are an issue right now? Or they don't think that contributions like using air conditioning less and things like that will actually make a difference?

Al Brown:

Well, if they just so happened to have a vehicle or want to take a light rail from downtown to the far edge where the light rail goes hop off the train and a walk around the neighborhood at the end of the line and compare to what it’s like on central and first, they'll certainly feel the difference right on their face. Whether it will make a difference, it is probably going to be difficult to measure whether adding say a thousand new trees will have a discernable effect on the temperature. But, it's going to provide those local experiences more shade and comfort. Especially on a hot afternoon when the sun is shining down, you are out walking around, bicycling, scootering, or wherever from place to place. Walking from one bus stop to another, or one light rail station to another. You are going to welcome the shade wherever you can get it. 

Cassandra Laubach:

I also had the pleasure speaking with student Corinne Johnson. Corrine is the president of the Society for Conservation Biology and they focus on environmental issues. On top of that Corrine is a double major and sustainability and conservation biology here at Arizona State University. 

Corrine Johnson:

The biggest easiest ways to help combat this is just sustainable education. Just informing people about their individual actions does have such a major impact on the environment. 

Cassandra Laubach:

You mention that you would like to educate more people about what they can do. If you were given the opportunity to educate, let’s say every student at Arizona State, what’s the one or two things you would say to them about the topic of urban heat islands?

Corrine Johnson:

One of the first things I would say to them is that this is a pressing issue that is happening now and it is our responsibility as the young generation that is currently living through this to take action on this. A lot of people think they can just push this issue off on someone else but that's not the case with this. It's every person's responsibility to help take care of their environment. And the second thing I would say to them is take pride in all of your actions. What you do does matter and even something as simple as unplugging electronics or shutting off your water if you're brushing your teeth. Little things like that have such a major impact so every single person can have a positive impact on the environment.

Cassandra Laubach:

Well that's all the time we have for this episode of The Forks Estate. Thank you so much to my three guests that participated in this podcast and thank you for listening. I'm Cassandra Laubach and I’ll see you next time. 


Previous Episodes:

Forks Estate: A look at what went into the making of the documentary 'Seeking Asylum' 

Forks Estate: A conversation about the March for Our Lives demonstration in Phoenix

News Update: Student government elections, new lab tech and the ASU football offseason


Reach the podcaster at cassandralaubach@gmail.com or on Twitter at @Cassandra_ASU

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