Smithsonian National Museum of Natural History

Webinar: Teen Earth Optimism – How Climate Change Affects Cities

Webinar: Teen Earth Optimism – How Climate Change Affects Cities 

Aired May 5, 2020

Meaghan Cuddy:

Hello, everyone. Thank you so much for joining us today. My name is Meaghan Cuddy, and I'm a museum educator at the Smithsonian's National Museum of Natural History. While our museum is closed, I'm coming to you live from my own home in Washington, D.C. Thank you all so much for joining us for our Teen Tuesday Earth Optimism Program. Today, we are going to be talking all about how communities are working with scientists to better understand how cities are being impacted by climate change and how they can use what they're learning to make positive changes in their area. We're going to be getting started in just a few minutes, as everyone joins our webinar today.

While people are joining, you can use the Q&A button at the bottom of your screen, that's the button with two speech bubbles, if you'd like to tell us where you're from. We'd love to say hello to some of you guys. All right. As everyone joins, we're going to go over a couple of details about today's program. All right. Let's see, we have Lisa from Mobile, Alabama. We have people from England, Virginia, Downtown Chicago. Hello. All right. Miami, Florida. Awesome. Scarsdale, New York. Very cool. Welcome all of you. As we get started and as everyone joins us, we're going to go over a couple of logistical things about the program.

You can use that Q&A box that you're all typing into right now. People from Maryland, New York, South Carolina. That's the box that you're going to use to answer any questions that we have for you today, and you can also use that box to ask questions of our scientist. We're going to be answering your questions during the second half of our program, so make sure that you stick around until then. Please keep in mind that those comments are only going to be visible to our Smithsonian staff, so we'd really appreciate if you could keep them all on topic. As a little reminder, we're super interested in hearing from all of you guys and hearing what you think of these programs.

After the program, you'll be getting a link to a survey, and we'd love to hear of your thoughts on how we can make this an even better program for our teenage audiences. All right, we're going to wait just a couple minutes while everyone joins. Hello, Caitlin from Richmond. You can use that Q&A box again to type in where you're from, and you can use it throughout the program today. All right, it looks like we have most people here, so we are going to get started. This series is about Earth Optimism. Thank you all so much for joining us. We all know that our planet is facing lots of different issues from things like climate change and pollution and a wide variety of human activities.

But here at Smithsonian and all around the world, lots of scientists are working really, really hard to understand these issues better and also to help come up with some creative solutions to some of these problems. Today, we're going to be exploring some of these issues with Dr. Jeremy Hoffman, who works at the Science Museum of Virginia. Jeremy's going to be telling us a little bit about his research and also giving us some ideas for things that we can do to be part of the solution. I'm really excited to introduce our scientist for today and turn it over to him, Dr. Jeremy Hoffman. Jeremy, how are you?

Jeremy Hoffman:

Hey, Meaghan. How are you doing?

Meaghan Cuddy:

Doing good. Thank you so much for joining us today, you and all your plants.

Jeremy Hoffman:

Yeah, yeah, thanks so much for having us. We're always excited to talk about urban areas and microclimates.

Meaghan Cuddy:

Very cool. Jeremy, you are the chief scientist at the Science Museum of Virginia in Richmond, and you're a climate scientist studying how climate change is impacting human communities in lots of different ways, including the urban heat island effects, and that's what we're going to talk a little about today. But where are you joining us from?

Jeremy Hoffman:

I'm here sitting in my apartment in Richmond, Virginia, just a short walk away from the Science Museum of Virginia and just down the road from Virginia Commonwealth University.

Meaghan Cuddy:

Very cool. Sounds like a very fun place to be. Before we get started, I'm sure a lot of our viewers are really interested in learning a little bit more about you. Can you tell us a little bit about what you do at the science museum?

Jeremy Hoffman:

Sure, and why don't I share my screen just to give you a visual aid. I have a really unique job at the Science Museum of Virginia. I'm the chief scientist, and I get to do a lot of what you see in these pictures, engage with people about the importance of science, especially climate science, in their day-to-day lives. Up in the top left, I'm using a really fun interactive display that we have called the Science On a Sphere that's developed by the National Oceanic and Atmospheric Administration, where I'm talking to journalists about the impacts of climate change here in Virginia and how they can better report on it to their readers and audiences.

Then on the bottom here, we have a field photo from campaigns we did to observe heat effect in Washington, D.C., which we'll get back to a little bit later on in this conversation. And then in the bottom right, you can see me giving a large-scale kind of lecture, a public presentation about the impacts of climate change right down on the block-to-block level here in Richmond. And then up in the top right, I get to design hands-on experiences for people of all ages, we like to say K to Gray, to learn a little bit about climate change and why it's important to them.

Meaghan Cuddy:

Awesome. Wow. You're really talking to lots and lots of different kinds of audiences about the science that you do. That's really cool.

Jeremy Hoffman:

Yeah, I get to even share with college-age students a lot of times, because I'm also an affiliate faculty member at Virginia Commonwealth University. I get to teach people from all ages a little bit about how science is all around them and climate science is important to them.

Meaghan Cuddy:

That's awesome. And that Science On a Sphere reminds me of the Science On a Sphere that we actually have at the Natural History Museum too.

Jeremy Hoffman:

That's right. They're all over. I guess there's a couple hundred of them worldwide, so it's a fun little network to be a part of.

Meaghan Cuddy:

Definitely. You have a really cool career, really unique experiences, and I bet some people are wondering how you found your way into this career, or is science something that you liked as a kid?

Jeremy Hoffman:

Actually, I think I had a different first love before I got really into science and hopefully this resonates with some people. I'm actually going to change my slide and show you a little bit about myself for when I was a kid. These are pictures from me growing up. I know many of the teens that might be on this call weren't alive in the '90s, but this is the kind of style that was around at that time. I swear.

Meaghan Cuddy:

Looks very '90s cool.

Jeremy Hoffman:

Yeah, it's like JNCO jeans and I think I had shaved my head and left the bangs. It's a really embarrassing time to look back on, but I think the more important thing to come away with from these pictures is not so much my hairstyles, but my love for fishing and the opportunity that I had growing up to engage with the natural world in northwestern Wisconsin, about an hour south of Duluth, Minnesota. My family used to go vacation up in these areas, and my dad and I would go fishing for fun to go catch the really big fish, but also for fish that we like to eat. I remember I learned a lot about the natural world and how to observe it from my dad.

He would track the number of rainfall days and how much it rained, and then compare that amount of rain to how high up the lake levels were on a rock that was partially submerged just off of the beach from where we would stay. These experiences really started to gain my ability to love the natural world and think of it as a place that I belonged. And then to tie it back into how I got then into climate change and why it's important to me at a personal level is that the fish that we really like to catch was known as a walleye. They live in really deep cold parts of lakes.

A few of my friends over the last several years have sent me newspaper clippings of newspapers in the area in northwestern Wisconsin that were reporting on these walleyes not being part of what people were catching anymore. It wasn't just people telling stories at the fish fry on Friday nights. The Department of Natural Resources actually became part of the conversation. By looking at the populations of walleye through time, they were actually able to confidently link this real decline in walleye to climate change. This feeds back into my own experience because the lake that we would fish on, and that's represented in the star here, warmed up by about a degree Fahrenheit.

While that might not seem like a lot, that has had a huge impact then on the ability for us to catch these walleye, which are foundational to my experience and my memories with my dad. Someday I would love for my nieces and nephews to be able to also enjoy walleye and eggs for breakfast on a Saturday morning. So then I bring it back to Virginia. Now, coming back to here and where I work at the Science Museum of Virginia, here in this map of Virginia, we have the streams as light colored lines, almost look like veins, and then the circles are individual temperature thermometers in the streams themselves.

The size of the bubble represents how far away from usual the present day temperatures are from the long term average. Red means that the stream has gotten warmer and blue means that the stream has gotten cooler. I hope what you see, Meaghan, is that not many of these at all are blue, and actually most of them are red, just like the lakes in Wisconsin, our rivers here in Virginia are changing, driving changes also to the species of fish that live within them. That kind of brings you full circle from where I was as a kid to what I'm doing now.

Meaghan Cuddy:

To where you are now. Today, we're not going to talk necessarily about how climate change is affecting the fish, although that is definitely something that's super-important and really interesting. We're going to talk about how it's impacting human communities and urban communities. What is the urban heat island effect? I know that that's something that you work a lot on.

Jeremy Hoffman:

Yeah, so the urban heat island effect is a really interesting phenomenon where the way that humans have built the way that we establish where we live. When you think of a city, what comes to mind? A lot of the times it's big wide roads, really maybe a lot of concrete or bricks and maybe not a lot of natural spaces. We think of it as urban versus rural. The urban heat island effect really boils down to the difference between these two pictures. Our urban areas kind of minimize the availability of natural landscapes like trees and green, low-lying vegetation, those sorts of things at the expense of very dense, hard, dark materials that we build our buildings out of.

This aspect of our cities actually absorbs more of the sun's energy throughout the day, and then reemits it back into the air as heat throughout the afternoon and into the evening. This actually means then that our cities are physically warmer than the surrounding natural landscapes at their edges and more wild places that don't have any human influence. We study how temperatures can vary between a place like the picture on the left and the picture on the right because that has huge impacts then on our health and well-being.

Meaghan Cuddy:

Our built environment is actually creating these microclimates, which is pretty incredible.

Jeremy Hoffman:

Yeah, that's right. As humans use cities more and more into the future, I think it's a majority of Americans live in cities and someday a majority of people all around the world live in urban areas, so better understanding how these conditions are right now better prepare us for the challenges of the future as the climate continues to warm due to the emission of heat-trapping gases from burning fossil fuels.

Meaghan Cuddy:

All right. How is this impacting communities and how our cities are designed?

Jeremy Hoffman:

That's a really good question as well. In order to answer that, I need actually some help and to challenge our viewers to help us in the Q and A box. I really need everyone that's watching the webinar right now to guess in the Q and A box. If we were going to fly into this picture, we're all on the magic school bus and fly into this picture, where is the hottest spot to the touch? If you are going to fly into this picture and put your hand on a surface, where is the hottest spot to the touch?

Meaghan Cuddy:

All right, so viewers, if you're looking at this picture, type into our Q and A box. Where in this photograph do you think would be the hottest spot based on the things that Jeremy just described? All right, we do have a bunch of answers coming in. Robert thinks it would be the asphalt. Vin says the parking lot. Jonathan thinks the concrete. Roy thinks maybe the cars. We have a lot of answers saying the cars in the car park, the asphalt. Jeremy, what do you think of the responses we're getting?

Jeremy Hoffman:

These are some very consistent hypotheses. Actually, what I love about facilitating this kind of guesswork is actually we're developing a hypothesis in our heads and you didn't have a scientist from the Science Museum of Virginia on board and not expect to do a little bit of science. This is really great. What's even better about this is that we have tools that we can use to test our hypotheses. A lot of people put forward their hypotheses. Let's actually test it using a sensor that measures the thermal signature, the actual energy coming back towards a camera that I can attach to my cellphone at this exact same time. Get ready, we're going to reveal the answer, Meaghan. Here we go.

Meaghan Cuddy:

All right, let's see if our hypotheses are right.

Jeremy Hoffman:

The brightest colors in this photo are the warmest temperatures. Many of you are correct that the asphalt, really dense, dark asphalt in the middle of the parking lot is the thing that's going to be by far the warmest temperature. But there is some really interesting stuff other than where the hottest spots are. The cars, many people brought up the colors of the cars, that has a huge impact on the emission or the thermal energy coming back off of that car is directly related to the reflectivity or the albedo of that surface. We can [inaudible 00:14:51] coming back, as well as the vegetation type.

We see this big oak tree in the top left, and we have some native plants on the upper part of the street here, and then the grass, this non-native European grass here right in front of the plaza, are all different temperatures. It turns out that the native plants from Virginia have really deep root systems that allow them to tap into water that's really deep down in the ground. But in effect, they have a better air conditioning system than the non-native plants that we tend to put around our cities. In a nutshell, it's the balance between these natural native landscapes and the built environment that we've made out of these hard surfaces that drives those impacts depending on where you are in a city.

Meaghan Cuddy:

All right. I mean, that makes sense to me. I know when it's really hot outside, I want to go under a really nice shady tree and that's going to help me cool down a little.

Jeremy Hoffman:

Yeah, I think everybody knows that when we get out of a car or get off the bus or whatever it may be on a hot day, the quickest way into a shadow is definitely the coolest way.

Meaghan Cuddy:

For sure. We've talked a little about this heat island effect and how the built environment versus green spaces differ and climate and why it matters. How has your work started addressing some of these issues?

Jeremy Hoffman:

Right. One of the key ways that we've been working on this issue is by using what is known as citizen science. Along with collaborators from Portland State University and several organizations around the city of Richmond, in 2017, we went out and actually collaborated on an urban heat island assessment campaign during a heat wave. We put these things that look almost like if you have a car flag to support some sports team that you really like. Just imagine this is as a car flag of science. The air flows through the top of that pipe and sends an electrical signal to a data logger, which tells us the temperature.

At the same time, a GPS unit is telling us where we are in this city in that car. By looking at those two things at the same time, we see a very highly descriptive map of where hotspots exist and where cool spots exist in the same city. Here is a picture of I'jiana James. She was a sophomore at Open High School in Richmond, Virginia, and a member of the Groundwork RVA Green Team. It's an organization that specifically works with teens to do greening projects around the City of Richmond and her involvement was really inspiring and students have followed up with projects related to the urban heat island effect afterwards.

This was just a really fun way to do it. Citizen science has been really our main way now in other cities to go around and form these teams to assess the urban heat island effect using these car flags of science hanging out of our vehicles.

Meaghan Cuddy:

Cool. You mentioned citizen science a couple times. Can you tell our viewers what is citizen science and why is that a good strategy for the work that you do?

Jeremy Hoffman:

That's a really, really good question. Citizen science, in many ways, can be called a lot of different things. You might hear it called community science, which is a little bit more inclusive word for people just that are part of our community. You might also hear it called participatory research. Really it's just making a scientifically rigorous measurement of something and then contributing to in many ways a long-term observational campaign that is used to analyze some phenomena in the natural world. A lot of the times, citizen science projects that have become really famous are things related to bird migration.

Do you see this one bird, or do you see this bug species, or what it could be? In our case, we're recruiting people to put these really sophisticated and accurate thermometers on their cars and drive around. They don't really have to do anything related to the technology, it's just participating and becoming a part of the team to figure out where to go. Citizen science is a really rapidly evolving field, from everything from air quality to birds to temperature to sound. You can participate in a lot of different ways.

Meaghan Cuddy:

That's so cool. It's really great to bring in the community, because who knows better about it than the people who are actually living there.

Jeremy Hoffman:

I think, Meaghan, you hit on a really good point there is that especially with climate change work, it's one thing for a scientist to show up to communities and say, "Here's data that you should use to change your neighborhood," versus "Hey, do you want to co-create and co-produce a data set that we can use to direct our resources together and have your voice and vision included in the planning?" I think that's what's really powerful about our citizen science campaigns is that we actually include these community members in designing where we're going to go in their own neighborhood to assess the temperatures.

That way we get a lot more buy-in from not only the community members and the residents, but then also the governments that might be pairing with us as well, like the Richmond City Government has been a huge collaborator on this project since its inception.

Meaghan Cuddy:

That is awesome. It sounds like a really, really cool project. What are you guys learning?

Jeremy Hoffman:

Oh, we're learning some amazing things. We can actually use the results of our heat island campaign that we did in Washington, D.C., to illustrate just how extreme some of these temperatures that we're observing can be. All right, we're going to need the teens again on this one to form a hypothesis in their heads and put it into the Q and A box. Using that relationship that we talked about from that picture, we're looking down from space at the District of Columbia and the surrounding areas in Virginia and Maryland.

Go ahead and put in the Q and A box where you think, using one of the labels on these places that you may not be familiar with, if you can see the type of land that's there, make a hypothesis about where we might find the hottest spot from this satellite image.

Meaghan Cuddy:

All right. If you were take a look at this image that we have, based on what we know now about urban heat effects, where do you think it would be really hot in D.C.? You can put your answers in the Q and A box and we'll read some of them out. All right. Columbia Heights, that's close to where I live actually, the urban areas, areas near the White House, in the middle of the map near NoMa, the river. The Library of Congress has gotten a couple votes. NoMa seems to be a really popular answer. Jeremy, what do you think?

Jeremy Hoffman:

These are all really good hypotheses, and I think I'm heartened to see that we've made that link between those dense urban environments and these hotter temperatures. It turns out that it can be a lot more complicated than just that, and we'll show you now what our results found. I'm happy to say that if you go to the August 2019 issue of National Geographic, our map of the Washington, D.C., area is actually featured in that issue. The redder colors on this map are the hotter temperatures and the cooler temperatures are represented by green colors. By and large, that's because the coolest areas were the densest, greenest areas. Places like Rock Creek Park were as low as 85 degrees Fahrenheit.

At the same time, on the same day, Columbia Heights was about 102 degrees Fahrenheit. That's an incredible spread, 17 degrees Fahrenheit difference between the coolest and warmest place at the exact same time. We can see all sorts of different things within that. Places like NoMa and even places like Shaw where there's like taller buildings, they actually cast some shadows on the streets that we can be walking around on or biking on and create a little bit lower temperatures. Anything in between exist all across the same area, but it's amazing how drastic the change can be just a few blocks away from each other.

Meaghan Cuddy:

Yeah, oh man! I know we're going to talk a little bit about how this is being used by some of the agencies that you work with, but I actually have a question for our viewers, Jeremy. Before we get into some of the solutions that you're going to talk about, viewers, if you are living in this neighborhood, what are some things that you would think would be a good thing to implement to reduce the heat island effects? How would you change these neighborhoods to make them more cool?

You can write your answers into the Q and A box for us. All right, we got some answers saying people would plant some trees. That might be a good option. Add some parks. Add rooftop gardens. Add some trees along walkways. Jeremy, what do you think? Are those some things that places you're working with are using?

Jeremy Hoffman:

Yes. I would hire all of these students for my urban planning department immediately if I could. One of the main long-term things that we can do is to plant more trees, for sure, but some more surprising and less intuitive responses to this have been increasing that building density along corridors that run maybe east-west, so that buildings on the south side are taller than the buildings on the north side and they cast shadows then onto those streets and surfaces below. There's this idea of the height-to-width ratio for your buildings versus your street. That can determine a lot about how you can promote shade without needing to wait for large trees to come into maturity.

Also, there are things like even water management practices, rain gardens that also help to retain more of that water and cool the immediate environment. Certainly different cool corridors. I saw trees along walkways. That's a huge way to promote health in these heat waves that are not only amplified by the city, but becoming worse because of climate change. I think that a lot of these strategies that people are coming up with in the chat or in the Q and A box are exactly the kinds of things that many cities are trying to implement to protect their residents into the future.

Meaghan Cuddy:

Cool. Jeremy, it's just about 3:25, so I think we're going to move on to a couple audience questions. Do you have some time to answer some questions for us?

Jeremy Hoffman:

Yeah, absolutely.

Meaghan Cuddy:

All right. Viewers, this is your chance to ask some questions of Jeremy. We're going to open it up to you. You can type your questions into that Q and A box and we'll read a couple of them out for Jeremy. I don't think we'll have time to get to all of them, unfortunately, but we're going to get to as many as we possibly can. You can type your questions in now. All right, and we already have some questions coming in, some really cool ones. All right, let's see. We have a couple questions about how different geographic features might impact this. Dawes would like to know, "Does the area near the river stay cooler? Is the river something that is going to make it a cooler place?"

Jeremy Hoffman:

By and large, proximity to large bodies of water tends to be something that creates what is known as an onshore breeze, because a large body of water doesn't have the same ability to swing in temperature as much as the land. A place like Baltimore, for example, another place that we've done one of these heat island campaigns, it does show these kinds of near-water cool sections based on where the wind is moving. It depends primarily on your location relative to that water body and whether the wind has enough time to travel over that cooler water to carry that coolness with it.

In the sense of the Potomac, it's not necessarily big enough to have a huge impact, but certainly we do see some of the areas right along the Tidal Basin and those sorts of things that do experience relatively cooler temperatures versus the more built up sections. But you can see a lot of areas that are right along the river don't show a lot of that cooling sense. It tends to be kind of a toss up. But cities with a bigger body of water tend to have a bigger impact of the local body of water than others with smaller bodies of water.

Meaghan Cuddy:

Cool. Wen Tao would like to know, "What are some things that normal people can do, people just like us, to impact this? What are some steps we can take to make this problem better?"

Jeremy Hoffman:

One of my favorite organizations in the D.C. area, but there are several of them around the world, are groups that work on trees. Casey Trees in Washington, D.C., is committed to increasing the city's tree canopy and by addressing some of these things like the urban heat island effect in their work. Another group is the Baltimore Tree Trust, which is a group out of Baltimore, Maryland, that does some really amazing work in Baltimore, working with the urban heat island map that they have to plant more trees. I think it's about finding that group that you feel like you can physically ... If you feel like you're physically able enough to go out and volunteer for these tree organizations, that's by far a great way to do it.

Another would be to sign up. There's a group out of New York called The Wild Center that does these teen climate summits. Lead your school through an organizational practice of climate action planning. That's something that you can take on with a big group of your friends if you'd like. I think really the solutions are both backyard, you could go and plant a tree yourself, to committing your group of friends to trying to do this climate action plan for your school. It's kind of a spectrum from that small scale to the big scale.

Meaghan Cuddy:

Awesome. Yeah, I actually used to be an intern at Casey Trees, so I can speak to the fact that they're a really cool organization in the D.C. area.

Jeremy Hoffman:

That's great.

Meaghan Cuddy:

All right. We got a ton of questions for you Jeremy. Rory would like to know, "What is the most difficult area you've ever worked in? Do you have any particularly fun stories or interesting things?"

Jeremy Hoffman:

Oh man. I will say that the heat campaign in Washington, D.C., was especially cool, no pun intended, because I got to go on the route that led me past the Washington Monument. I actually drove the vehicle that went through the National Mall and along into the area right by the yards and where the new baseball stadium is. It was just such an interesting thing to be in a place that has such rich history for our country, and then to be contributing to the scientific knowledge of that space was just so rewarding to me personally and professionally. Plus, my family has history here, too. My mom grew up in Greenbelt, Maryland, just outside of the Washington, D.C. area.

Being able to connect with that family story was really important to me as well. That's a really fun place to have worked. And then in my Ph.D. work, I went to Nova Scotia, Canada, actually and got to work in an oceanography lab in there for a little while. That area of Canada is beautiful and has this really amazing history from during the last ice age being completely scoured down to the bedrock that you can see exposed everywhere. It's like a couple billion years old. You can see the history of the world all in front of your eyes.

Meaghan Cuddy:

That is so amazing. Everyone, it is about 3:30, which is the end of our planned content for today, but we do have a ton of amazing questions and we'd like to get to some more of them. Jeremy, do you have a couple extra minutes to stick around to answer some questions?

Jeremy Hoffman:

Absolutely. I'd love to answer them.

Meaghan Cuddy:

Awesome, thanks. Jeremy's going to answer some more questions if our viewers would like to stick around. If you do have to go, thank you so much for joining us, and remember that this and all of our other video webinars will be posted on the Natural History Museum's website. As one other reminder, we'd really appreciate it if you could fill out our survey. The link is going to be posted in the chat box. But Jeremy, with a little bit more time, will answer some more questions.

Jeremy Hoffman:

Wonderful.

Meaghan Cuddy:

Okay. Sayed would like to know, "Does electricity affect the urban heat island?"

Jeremy Hoffman:

In a certain sense. We think of electricity, hot, and it does turn out that in very small spaces that anthropogenic heat or big engines or cooling systems, things that are using a lot of energy can create locally very, very small heat islands of their own. For example, in the City of Chicago on Lower Wacker Drive, there are a bunch of hotels right along the Chicago River. The cooling systems and heating systems for those hotels can create a little heat island in the middle of the winter.

If you drive on Wacker Drive, it can actually be relatively warmer in a frigid cold environment because of these big human systems. It has to be a really dense array of these things that are generating a lot of their own heat to have a big effect at the city scale. It's much more related to the area of paved dark surfaces that tends to amplify these heat waves much more than these individual things that might be using a lot of electricity.

Meaghan Cuddy:

Okay, cool. Nick Yu would like to know, "How does the study of area-specific heat islands, so these small urban heat islands that you look at, connect to the study of climate change as a worldwide phenomenon?"

Jeremy Hoffman:

The key thing is that the climate change at a worldwide scale is loading the dice for there to be more intense heat waves. That's one of the outcomes of global climate change. By and large, our climate is warming up. That's going to tip the scales towards these more intense heat waves through time. What's important about the work that we do is that cities and the way that they're designed, excuse me ... Sorry. Cities can then further amplify these extreme heat waves. For example, in 1995 in the City of Chicago, there was a big heat wave that was regional. It went all over the Chicagoland area.

I was growing up there at the time. My family was able to have ... We had a backyard with a baby pool and air conditioning and all that kind of thing. But at the same time, just a few miles away in a particular area of the city where they didn't have those kinds of natural green environments, it was much hotter and people lost their lives because of the built environment and how it's all related to one another. You can think of it as climate change is making it worse overall, and then the way that our cities are designed can add on top of that to the extremity of the heat waves.

By understanding where these hotspots exist, we can better and more effectively and efficiently put resources into those areas that can address that additional heat from climate change.

Meaghan Cuddy:

Cool. Lucius has a question that's kind of connected to that idea of using this information. He'd like to know, "Are you talking to reporters about what you're finding and what might be causing climate change?"

Jeremy Hoffman:

Yes, I talk to reporters as much as we can. In fact, I think as part of the blog post or accompanying post to this webinar, there will be some interviews that I've given with people at WAMU, the local radio station in Washington, D.C., where I talked to Jacob Fenston and actually brought him around on a drive with me in the D.C. campaign, as well as Kojo Nnamdi, who has The Kojo Nnamdi Show. And then some of our work has been recently featured in National Geographic and The New York Times. If you just search urban heat islands and Jeremy Hoffman, I'm sure you'll see some of the interviews that I've given with various reporters from around the country.

Meaghan Cuddy:

Cool. Lucius just also says thank you for answering his question.

Jeremy Hoffman:

You're welcome, Lucius.

Meaghan Cuddy:

All right. Sophie would like to know a little bit about some other ways that cities are dealing with this. She wants to know, "Should we be painting buildings different colors?"

Jeremy Hoffman:

Well, if we learned anything from that picture of the parking lot that in some ways, yes, definitely providing the ability to have more reflective roof surfaces, more white roofs, certainly can have a huge impact than on the temperature of that roof and the areas around it. By promoting these more reflective colors, we can actually reflect more of that incoming solar radiation, then cool the places down. What is an interesting problem about that is that by reflecting the sun's energy, we can actually sometimes, according to some models for Los Angeles in California, that by changing all of the roofs to white, we would actually change the chemistry of the air and promote smog formation.

There's some of these cascading impacts that I think in many ways we need to address the urban heat island effect not with a silver bullet, but with silver buckshot, if that makes any sense. A bunch of solutions all at the same time, instead of just one.

Meaghan Cuddy:

For a really complex problem, it's going to take a complex suite of solutions to deal with it, I would imagine.

Jeremy Hoffman:

Yeah, absolutely. Just like climate change.

Meaghan Cuddy:

Exactly. Emma would like to know if you know where in the world is most impacted by this urban heat island effect?

Jeremy Hoffman:

Oh boy. Well, so far in the United States, we've measured close to 15 to 20 cities at this point. It seems like 15 to 17 degrees Fahrenheit is a pretty common high and low difference on in the course of a day. But a city in New Mexico, and I forget which one exactly, was upwards of 20, 25 degrees Fahrenheit at the same time. A metric could be like how different is the coolest and warmest place or how big spatially is the urban heat island effect more generally.

The really big cities in East Asia, places like Shanghai, Beijing, New Delhi. Large ... London, for example, has a pretty well established urban heat island effect. It's really, are you concerned with the size of the urban heat island, or the difference between the coolest and warmest place? Because then there are different places that might have either larger or smaller differences according to that.

Meaghan Cuddy:

Yeah, that makes a lot of sense. Dawes has a question about urban planning. He'd like to know, "How practical is it to add trees to all of these spaces? How are people making these decisions?"

Jeremy Hoffman:

Well, as I mentioned before, it takes a long time for trees to reach maturity. In many ways, by planting trees that are very small, their full canopy shade won't be realized for 15 or 20 years. Excuse me, I just caught the hiccups.

Meaghan Cuddy:

Happens to the best of us.

Jeremy Hoffman:

I get hiccups when I talk about exciting things like urban heat islands.

Meaghan Cuddy:

That's very exciting stuff.

Jeremy Hoffman:

And then there's the question of where to plant them. Many times we've seen in other cities that some people frankly don't want trees in their neighborhood because they perceive it as a place that will either harbor people that want to break the law, or that'll throw tree limbs on my car, or birds will provide excrement for my car, roof, or window. In some ways, I think that we need to acknowledge that some neighborhoods have their own vision for what they want to see and how they want to address this issue.

Part of the process of our campaigns is to figure that out, and then to advocate for those solutions based on what people actually want. Instead of just saying, "Well, we're going to plant a million trees everywhere," let's have a conversation around what might work best for the neighborhood that we're working with.

Meaghan Cuddy:

Yeah, and that's the cool thing about citizen science is that you get to hear the perspectives of the people who are going to be impacted the most, the people who are right there.

Jeremy Hoffman:

Yeah, absolutely. That's why I'm optimistic about the future.

Meaghan Cuddy:

All right, cool. We I think have time for one more question. Are there any websites or resources that you know of that people can use to find out how they can get involved in this kind of work?

Jeremy Hoffman:

Yes. There are several options for you out there. The best example of how to get involved using just your own smartphone is to look up the app ISeeChange. It's basically like Instagram, but you can observe temperature, precipitation, changing seasons and those sorts of things. Think of it like a nature journal for yourself, and that actually provides a lot of information that's useful to scientists at the same time.

ISeeChange is one of them, but then also the NASA GLOBE Project, that has some citizen science projects related to surface temperatures and air quality, as well as cloud observations. You can just go outside and take pictures of clouds if you'd like to. But I think it's important just to get involved with what you think is interesting because that will drive your interest for college or whatever comes next for you. Just being curious is really important.

Meaghan Cuddy:

It sounds like there's a lot of really cool ways for people to get involved in this and to be scientists in their own backyard, which is amazing.

Jeremy Hoffman:

Yep, I agree.

Meaghan Cuddy:

Awesome. Well, that's all the time we have for today, but Jeremy, thank you so much for joining us.

Jeremy Hoffman:

Thank you so much for having me, and thank you everybody for tuning in.

Meaghan Cuddy:

Yeah, thanks everyone. We really appreciate all of your awesome questions. Thank you so much for participating in this program with us. If you enjoyed today, please join us again next Tuesday at 3:00 Eastern Time. We'll be talking to Dr. Melanie McField about how scientists are working to help protect coral reefs in the Caribbean. You can always check out our other video webinars, and you can see the full schedule of our programs on the Natural History website, which will also be posted in our chat. As a final reminder, we'd love to hear your feedback in our survey and know what you'd like to see more of. Jeremy, thank you so much for joining us today. I learned so much. I had a great time.

Jeremy Hoffman:

Thank you so much. I learned a lot as well. Thank you, teens. It's a joy to get to hang out with you for a little bit.

Meaghan Cuddy:

All right. Have a great rest of your day, Jeremy. Bye.

Jeremy Hoffman:

Thanks. You too. Bye.

Archived Webinar

The Zoom webinar with climate scientist Jeremy Hoffman aired May 5, 2020, as part of the Teen Tuesday: Earth Optimism series. Watch a recording in the player above.

Description

In this program, climate scientist Jeremy Hoffman explores how citizen science is being used to combat climate change in urban areas all across the country. Jeremy talks about how his research is being used to create more sustainable cities, and why he is optimistic about using the power of communities to address climate change in our own backyards. 

Related Resources

Resource Type
Videos and Webcasts
Grade Level
6-8, 9-12
Topics
Earth Science, Engineering and Technology, Physical Science