In the last decade, there has been a mass migration of people into urban areas across the globe. This rapid urbanization has been increasingly unsustainable for our cities and it’s projected to get worse in the next decade.
University of Chicago scholar Luis Bettencourt is tackling this global crisis by researching the underlying processes that dictate our cities. If you can understand the numbers, you can create models for the sustainable cities our planet needs. He’s starting by mapping a million neighborhoods.
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(Episode published October 23, 2019)
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Paul Rand: Close your eyes and picture a city. What do you see? Cars and busy streets? (Sound of cars) Buildings? Subways? When Luis Bettencourt pictures a city…he sees math.
Luis Bettencourt: You can imagine that is sort of a big matrix of interaction right. Mathematicians call that a graph.
Paul Rand: Numbers...
Luis Bettencourt: So when you think about any kind of mathematical modelling particularly when you carry it over to cities and to human societies, it's about the most basic stuff right.
Paul Rand: Equations…
Luis Bettencourt: But the fact is all this sort of more mathematical understanding of how cities actually work allows you to do that planning. And understand that as the city for example grows, it doesn’t mean you just proportionally add streets and buildings there’s a qualitative transformation.
Paul Rand: Luis Bettencourt is a Professor of Ecology and Evolution at The University of Chicago and the Director of the Mansueto Institute for Urban Innovation.
Luis Bettencourt: So the idea is really to think about cities in a way that that allows us to think about the great problems and solutions that are necessary going forward for an Urban Planet.
Paul Rand: When Bettencourt says Urban Planet, he isn’t kidding. In the last decade there has been a mass migration of people to urban areas across the globe. This urbanization has been dangerously unsustainable for our cities and it’s projected to get worse in the next decade. Bettencourt’s research explaining the math behind how our cities function couldn’t come at a more crucial time. Because if you can understand the numbers...you can create models for more sustainable cities.
Luis Bettencourt: We still have lots of problems about conflict and exploitation and market failures about how cities work. We have of course the problem of sustainability and health. The fact that a lot of how we run our energy and resource systems is unsustainable. And so we need to change those while preserving what is good about cities.
Paul Rand: From the University of Chicago this is Big Brains, a podcast about the pioneering research and pivotal breakthrough reshaping our world. On this episode…Luis Bettencourt and the future of cities. I’m your host Paul Rand.
Paul Rand: Bettencourt is working with a team of researchers, technicians, urban planners, and even the United Nations to form a global urban sustainability project. One that he hopes will re-shape the future of our cities for the better. But before he was one of the world’s leading experts on urban development...he was actually a physicist.
Luis Bettencourt: I think growing up and sort of being a curious kid in school, I got interested in science. And physics was really sort of the ultimate science. It is a culture of thinking about the world more than it is a subject matter. It's sort of a way of thinking about processes in the world how things work.
Paul Rand: Right.
Luis Bettencourt: And then from that perspective kind of pushing on them a little bit to see where they lead. So you can see for example how certain forces may create a crystal or how gravity may create a star or the earth or a galaxy.
Paul Rand: Right.
Luis Bettencourt: So from the point of view of you know things processes, dynamics you can end up with very different end states, different things that are created and that work in different ways. And so that's a very powerful and generative window into the world.
Paul Rand: Bettencourt began to see that—in the same way there are processes that dictate the laws of physics—there are also processes that underly the way people interact and organize themselves. And when he was just a fledgling scientist, a health crisis across the world gave him an opportunity to put his ideas to the test.
Luis Bettencourt: There was an epidemic outbreak of a terrible disease called Marburg virus in Angola. There were these reports in major publications in New York Times and others about this crazy disease. It's a bit like like Ebola is a bad way to go. What happens with this kind of diseases is that people sometimes first under underreport because they don't know it exists. So they attribute what's going on to other diseases and then over report when there's a bit of panic. And you know the numbers had a certain logic. So you know I just started playing with the numbers and made a model and I could make a prediction and at some point I was following it. A bit like weather prediction. And then I got in touch with people at the World Health Organization saying this thing you just reported has to be wrong such is the hubris of youth.
Paul Rand: Did they respond back and think that it was really beneficial what you were helping them understand.
Luis Bettencourt: I didn't get a lot of constructive criticism but they did review the numbers and it was wrong eventually but it took a long time to figure out. But that was the beginning of a model of networks, how people transmit diseases and how this is mediated through a society. And it was a way to take a few numbers that were just in the media and being able to say something interesting maybe important practically.
Paul Rand: As Bettencourt became obsessed with understanding the math behind the networks that mediate human societies, it was inevitable that his research would begin to focus on the places with more human interactions than anywhere else:cities.
Luis Bettencourt: And so when you think about a city it's frankly about how people exist in space and time right. So this is kind of interesting as a way of thinking it's a distinction between the thing you, you know the buildings the roads the trains the cars and the things that are going on the processes right. So from that perspective you say okay what are those processes? They’re essentially people living in place but then interacting with each other. And it's those interactions that make the city so you can have cities. So all this we've been discussing you can put in math.
Paul Rand: Right.
Luis Bettencourt: So the city is really when you do the math of it if you will in terms of what we just described is how you put these two networks together the network of interactions between people and their network of things. Now the magic is that you can turn that into a mathematical set of evacuations that predicts numbers.
Paul Rand: What do you mean?
Luis Bettencourt: Well you can tell for example how much more street you need as you double the size of the city. Or you can say how much the GDP is going to grow and understand that as a city for example grows. It doesn't mean that you just proportionately add streets and buildings actually there is a qualitative transformation.
Paul Rand: Once Bettencourt understood the mathematics…he could explain the dynamics of how cities function and answer some important questions. Like, why is it that high concentrations of people create benefits for the entiregroup? Bettencourt found an answer in something he calls the multiplicity effect.
Luis Bettencourt: So I think everyone has an intuition for this. You visit sort of a large city and you tend to see new things. You tend to see that people tend to make more money but also spend more money. So things are kind of amped up right. There are more things per unit space. There’s high density. These are all sort of multiplications there is a percentage intensity that kind of grow with the size of the city disproportionately, so not proportionately, but disproportionately to the number of people and the size of the space of the city. That intensification comes across as a feeling a lot in terms of speed and density. So space is compressed and times accelerated. So that's why we all feel stressed in larger cities right. But it's also exciting at the same time. So that effect, you can do that math again so this is the magic of it and get numbers out for how much things increase But the idea I think became most clear in technology, with the Internet So the that come out of a network, so a system of interaction or interacting with other people is often not to do with the number of participants, the number of people, but the number of links. And those essentially grow like if you didn't have space and constraints would grow like the square, the number of people times the number of people again. So that's what gives you the sound vilification. By intensifying and multiplying interactions you can multiply the things being exchanged and potentially the benefits sometimes the costs of what is going on in these networks.
Paul Rand: So let's talk about what if this is not done well. What what what do you see when this isn't working you know in a planned purposeful way.
Luis Bettencourt: Right so more interactions can mediate more violence.
Paul Rand: Right exactly.
Luis Bettencourt: So thats crime, violence etc. But that tends to make the system disintegrate. So it's a little bit self-regulating but, of course you'd like to avoid it in the first place. And if you understood the logic of cities as we've been talking about you would have.
Paul Rand: You start constructing for it. You realize what the implications are for not building these safeguards and deciding what you're going to be prescriptive on and where you're going to leave some freedom.
Luis Bettencourt: That's right. We often approach cities at least in our daily lives and our policy through our frustrations. You know through the things that don't work or the pollution of the congestion or the costs. But you know I always play this game of asking people so do you live in Chicago or the city you live in because of its costs, because of its crime rate, because of this or that. And they say no. So why do you live in Chicago? And obviously the answer is because I have opportunities: I like my job or I like my friends or you know it's because of how you embedded in terms of what you do and the people you know. And so this is true everywhere. And that's the mechanism by which people open horizons for what they are and what they could be.
Paul Rand: In the United States, there’s a general trend of people leaving major cities. But the rest planet is urbanizing. The numbers of people projected to move to major cities over the next decade are staggering. Bettencourt says this could be a massive opportunity, or a disaster. Will we develop ways to create sustainable cities, or degrade our cities into anarchy? Bettencourt is working on a globe-spanning project that he hopes will lead our cities into the future. That’s after the break.
Paul Rand: So the concept of cities right now my understanding is that the number of people that will be moving into urban areas whether it's just natural moves or because of everything rangeing from climate change or other weather conditions is really pretty meaningfully increasing is that right.
Luis Bettencourt: That's right. It's very different in different parts of the world has to be said. But this is a moment where most people in Asia and Africa. So the two continents that have the largest amount of populations and still the fastest population growth are urbanizing.
Paul Rand: What kind of numbers are you looking at increasing wise?
Luis Bettencourt: So the estimates vary a little bit but we are looking at several billion people maybe a couple billion people moving to cities or living in cities through natural births in the next few decades.
Paul Rand: And this migration presents some massive challenges. Many of the cities are already dangerously full. So, people end up creating new neighborhoods on the outskirts. But these places are often devioid of resources and infrastructure. They’re part of the city and yet separate. These areas are among Bettencourt’s biggest concerns.
Luis Bettencourt: It’s estimated that almost a billion people around the world live in slums today. It is a neighborhood in a city, could be outside a city, where people occupy land but they don’t have a legal staus or services or addresses or street neitworks.
Paul Rand: It was on a research expedition to one of these neighborhoods that Bettencourt got the idea for his new project.
Luis Bettencourt: This was in Accra in Ghana and there's this very special neighborhood called Old Fadama but It's also known as Sodom and Gomorrah I think by others. It is a neighborhood of people who work so porters and workers in the market in the Main Street Market of the city. So this is the market where all the food and all the goods come into the city and then get distributed. They’re sort of on all lagoon and so part of the neighborhood was exposed to sea rise. And so they had to move some of the structures and so they managed to be in contact with the city to relocate and then rebuild some of that part of the neighborhood. But as part of that what they had done was to create a street network. They themselves like the residents. Right. And you say why are you using space where you know you obviously have lack of space and they said no look this way we can carry stuff through the fire engine can come, the ambulance can come and you know people like the shops along the streets. And so for me this is very interesting because of course I had read tons of urbanism and history of cities. And that's the same process that anyone will describe cities evolve by you know historically, not as plans in the 20th century but sort of as the gradual evolution of neighborhoods that makes them interesting. So I started thinking about that and I thought well you know it's the same thing we talk about with the networks right. So what you have here is sort of a network of people and places like the places where you live and work the buildings that need to be interconnected by a common space in which you can circulate and deliver functions. And I said but that's a math problem right. And so we thought if it's a math problem we could do it everywhere. So we started working on this you know a few years later we came up with some practical ways to look at any neighborhood, look at what streets exist, and what places exist find if they're connected or not and if they're not connected what little bits of connection could they use such that that evolution of the neighborhood is gradual. And so this is something people call reblocking but that you know you can have an algorithm suggests something because it's math. But then we put these solutions in the hands of people such that they tell us it's dumb or they want to do something else and you'll tell them you'll have to build more but that becomes an interactive process based on data based on maps that solve sort of a complicated development problem.
Paul Rand: If data from one neighborhood could give you solutions to problems of urban development more broadly, imagine what you could learn from compiling the data from a hundred neighborhoods, or a thousand. Bettencourt went even further by developing the Million Neighborhoods Project.
Luis Bettencourt: It's both a network of people that have agency in the space and then a supportive technology that allows us to be talking about my neighborhood, your neighborhood neighborhoods all over the world so a million neighborhoods.
Paul Rand: The more data, the more math, the more math the better we can understand the processes of sustainable development, the more processes we can understand the more we can and share them with developing cities across the world.
Luis Bettencourt: The idea is that if you want to address issues of equity and inequality this has a very strong place based so neighborhood by neighborhood expression in any city and neighborhood lenses allows you to see these inequalities and also creates accountability in a way they essentially is collaborative so that we where it makes sense are trying to address similar problems learning from each other but also creating the scale not working just parochially just one neighborhood at a time but creating the scale in which some of these problems emerge is common across many places and then justify and encourage the participation of people like us who are researchers who wanted to work on general problems to some extent at least while people in technology or business that also want scale in order to create solutions.
Paul Rand: Okay. So now you had your gathering a lot of data. What do you do with it.
Luis Bettencourt: So what's special is that you can do this. So there's just this moment of opening up vision where you can look throughout the world and see every neighborhood. Everything about the built environment certainly
Paul Rand: Is this like Google Maps or something different.
Luis Bettencourt: It's a bunch of things that feel like Google Maps but Google Maps belongs to Google and so it's largely proprietary. But most of this data is coming from remote sensing so people with satellites that are ever more precise. OK. So you can now have basically see everything in a in a photo from a satellite that's in about the size of your hand. So that means that just in the last few years you can see objects instead of just a blur of a city. So I call that that we reach the urban scale. So this is very special. We've seen cities we've never seen before building by building street by street. So so there's mapping that is just happening and coming through all these different avenues and then there's a lot of community organization also that using maps as sort of an instrument to express their own reality and communicate what they have and what they don't have. And so the map and sort of the urban plan are becoming fluid and that's a very interesting situation where not only can we see things for the first time we can also animate those things into future possibilities. So that's what we're doing is basically have a map of the world neighborhood by neighborhood highlighting the places that are lacking infrastructure and street networks. That technological platform is a way to also hold these ideas of collaboration, put everyone as I like to call it on the same map. So putting people on the same map is also a bit of a political strategy so that they see at least some of the same reality and work together toward some of the same solutions.
Paul Rand: So by gathering all this data you're starting to see what on a broader scale at different stages of development.
Luis Bettencourt: That's right.
Paul Rand: What's working at which stage and where can you be guiding people to help learn from others.
Luis Bettencourt: And we have in many places of the world we have a network of people that work in each neighborhood like we all work a lot of people in West Africa and India of course in Chicago. So they have specific problems sometimes they’re common, sometimes they're quite different. But the idea is that there's a process of organizing communities and working between the city and the community in a way that creates a model of policy and urban planning that is much more collaborative. But then that requires to be fast and sustainable new elements that are not typical of what people can do locally. So that's very important then to bring in people who are researchers who are at the forefront of technology and other capabilities that allows us to create fast sustainable development quickly such that you know a billion people are not in slums but that development is also sustainable.
Paul Rand: The Million Neighborhoods project holds a lot of promise for addressing some of urbanization’s gravest challenges. In fact, it holds so much promise that even the United Nations has gotten involved.
Luis Bettencourt: Exactly. So in the in the context of the United Nations since 2015 there have been a series of international agreements that set policy till 2030 and maybe a little bit beyond. It’s called agenda 2030. And there are several things about that including the Paris climate agreement and some other things. But the central connecting tissue for that is something called a sustainable development goals which has 17 goals with metrics. They're supposed to apply everywhere. And when you look at them they're really about solving all the great problems of humanity and our relationship with the environment in the next 10 years. So in October we’re convening a global symposium on sustainable cities and neighborhoods. If you go back a few decades we're thinking about sustainability and development at the national level, at the global level, looking at global problems of climate. But increasingly what's been happening is that cities and their neighborhoods are really becoming the focus of agency where people feel they can do something about that transformation. Where there can be accountability because very close to people's experience and where there can be social capacity to also create change. But the challenge then is to create sort of a bit of a movement that's enabled by new knowledge and new technology as well as local priorities that can create that network of development. So we bringing people from all over the world to try to basically pose that challenge and try to articulate a vision going forward. So what we hope will come out of this event is really obviously a set of collaborations but also sort of a plan a set of ideas that allows us to reframe the process of sustainable human development in cities and neighborhoods with this local focus that at the same time cuts across scales that creates you know walkable local and sustainable cities. But at the same time solves the kind of issues of urban planning and development that we're facing the next decades.
Paul Rand: Bettencourt spends a lot of his time and energy addressing the pitfalls and challenges of urban planning, but he retains a powerful sense of positivity and optimism about the ability of cities to improve our world. That’s coming up after the break.
Paul Rand: Despite the concerns of urbanization, Bettencourt still sees cities as beautiful, powerful things that can generate immense good in our world.
Luis Bettencourt: You think about what cities do, how is it that they could do the same thing better and in a sustainable way. So some things are obvious you have to imagine replacing existing infrastructure with infrastructure that doesn't use for example fossil fuels. But all that you know you could end up with almost with the same looking city. You know electric car substitutes diesel car and it looks the same. But the real opportunity, the thing that gives you these multiplicative effects that allows cities to be agents of growth, is that they're not just about substitution of the material of the thing but that they're creating new possibilities have new information for new kinds of solutions for the way we use these things whether. You know whether we use cars and more like a hybrid between public transportation and private transportation or that you know as we electrify cities there'll be all these gains in efficiency. Now what needs to happen though is that some of the bad things are still with us. We still have lots of problems about conflict and exploitation and market failures about how cities work. We have of course the problems of sustainability and health. The fact that a lot of how we run our energy and resource systems is unsustainable. And so we need to change those while preserving what is good about cities. And I think it's perfectly possible to imagine how that transformation will occur and if you allow me to be to go big and be a little bit whimsical, it's something that even from the perspective of how we function as a species is profound. If we go indeed to a logic in which our energy doesn't come from burning stuff and plants ultimately and the sun we'll be the first sort of natural species that gets its energy from the source right from the sun and its consequences. And it's not therefore in competition. If we do it well with life in order to create a good human society.
Paul Rand: There's a lot of people like to see that happening.
Luis Bettencourt: Yeah exactly. But we have to learn how to do that both operationally which there's a lot going on but we don't know if it's fast enough. But also then to turn what has been sort of a relationship that's been negative exploitative into one that's positive. Right. We'll be bringing energy and resources into nature in ways that didn't happen before and into human societies in ways that they can function better.
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