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0:03
- Good evening, and welcome.
0:07
My name is Joshua Brumberg. I'm the Dean for the Sciences here at the Graduate Center. As you know the graduate center is the primary doctoral granting body of the wonderful enterprise that is the City University of New York. Here in what is the former B. Altman building, we are a nexus of scholarship, across our many programs, centers, and institutes, teaching over 4,100 students. In turn our doctoral students go out and teach over 200,000 CUNY undergraduates at the CUNY campuses across the
0:37
five buroughs of New York City. As a community of faculty and students committed to the ideas that learning is a public good, the Graduate Center regularly offers public programs featuring eminent thinkers, writers, artists, and scientists. The GC is not just an institution dedicated to advanced education research. They're also a place of ideas, where issues are framed in new and creative ways and shared with the city at large as we'll be doing tonight.
1:06
Tonight's event is a prime example of that, and it's the second of our newly launched series The City of Science. We are very fortunate tonight to have many distinguished CUNY researchers here to talk about urban habitats. I will briefly introduce each of the speakers prior to handing off to the MC of tonight's event, Professor Charles Vorosmarty, who will moderate this evening's discussion. Our first speaker will be Dr. Deborah Balk, who is a Professor of Public Affairs
1:34
in the Marxe School of Public and International Affairs at Baruch College, and in the economics and sociology doctoral programs here at the Graduate Center. An Associate Director of the CUNY Institute of Demographic Research. She is also a 2016 Andrew Carnegie Fellow. Her research focuses on urban demography, and low and middle income countries. She combines demographic and spatial frameworks to examine urbanization and related demographic behaviors with respect to environmental factors,
2:03
in particular climate change. She will be followed closest to me by Dr. Peter Groffman, a Professor of the City University of New York's Advanced Science Research Center, and Brooklyn College's Department of Earth and Environmental Science, as well as being a member of our doctoral program in Earth and Environmental Sciences. He has research interests in ecosystems, soil, landscape, and microbial ecology, with a focus on carbon and nitrogen dynamics. Sitting next to him is Dr. Peter Marcotullio,
2:33
who is a Professor of Geography at Hunter College, and the Director of the CUNY Institute for Sustainable Cities, and an associate of the CUNY's Advanced Science Research Center, and also a faculty member in our Earth and Environmental Sciences program. His research focuses on the intersection of urbanization, energy, and the environment. He is the lead author, for the soon to be released Energy Systems chapter, and contributing author for the Urban chapter in the second North American
3:01
State of the Carbon Cycle Report, and you'll be seeing running in, coming from Penn Station at some point. One of CUNY's newest faculty members, Dr. Andy Reinmann, who has just started as an Assistant Professor in the Department of Geography at Hunter College, and at the CUNY Advanced Science Research Center, Environmental Sciences Initiative. He is a forest ecologist and a biogeochemist, whose research explores how tree growth, forest productivity, and the movement of carbon and nitrogen
3:29
into and out of the ecosystem, respond to human activities such as climate change, urbanization, and habitat fragmentation. Finally, tonight's discussion will be led by Dr. Charles Vorosmarty, who is the founding Director of the CUNY Advanced Science Research Center, Environmental Sciences Initiative. An Einstein Professor of Civil Engineering at the City College of New York, and a member of our doctoral program in Earth and Environmental Sciences. Dr. Vorosmarty, routinely provides
3:57
scientific guidance to a variety of U.S. and international scientific organization. He was a founding member and for a decade, the co-chair of the Global Water System Project that represented the input of several hundred international scientists, under the International Council for Science Global Environmental Change program. He has served on a broad array of national panels, including the U.S. Arctic Research Commission, the NASA Earth Science subcommittee,
4:23
The National Research Council on Hydrologic Sciences serving in that capacity as its chair, and The National Science Foundation's Arctic System Science program Committee. He is also consultant to the United Nations, and it is now my distinct pleasure to turn over the microphone to Dr. Vorosmarty who will introduce tonight's program. (audience applause)
4:51
- Thank you, Josh.
4:53
I think as you all must know by looking at the flyer, that's been on for the last few minutes, and perhaps when you saw the advertisement on the web, the subject of tonight's discussion will be cities, but it really is about a planetary scale experiment in transforming planet Earth, from what's traditionally been viewed as a rural humanity with its rural populations, and rural landscapes, into what has increasingly become an urban dominated planet. Now, I've chosen some imagery here
5:28
that's going to loop a few times. I think it's a little shorter than my opening remarks here, but it comes from a movie that was released back in 1982, which actually affected me quite strongly, from an artistic standpoint, that I realized should also influence me scientifically, and the way I think about things in general, and it's actually quite a brilliant little exercise. Koyaanisqatsi, was the name of this movie. It's called, Life Out of Balance.
5:56
It's a Native American term meaning life out of balance. It was an attempt by the Director, Godfrey Reggio, who was an American Director, to begin looking at life in what was then the late 20th century from some very different perspectives. Combining experimental technologies in film with perceptions of life around us, and what he did was actually quite brilliant, and we study as engineers and scientists, different dimensions. X, Y, and Z, length within height, plus time.
6:34
Four dimensions that we typically look at changes unfolding on the planet, or we design transit systems, et cetera, and he took one of those dimensions, simply the time dimension, and he distorted it, and as you can see, it's all sped up, and certainly my comings and goings in New York City, I have not any inkling of this kind of perspective. You actually have to speed things up, and when you begin to speed things up in this one domain, you see all sorts of interesting things happening.
7:04
You see people coming together, and compressing as groups of people, and then you seem to see them disperse. They're stopping to cross the streets. Traffic goes, traffic stops. Traffic is moving through the sinuous. I don't know if that's part of this particular video,
7:24
but you have these beautiful scenes of highways filled with cars, and we can see their infrastructure, whether it's mobile infrastructure, or sedentary infrastructure, like houses and buildings, and we see the people there, and it's not hard to take the jump to say, hey, implicitly, we're seeing materials and energy flows that are going through the system. What makes the city tick? It's people, it's energy, it's materials. It's the infrastructure, and by just distorting that one dimension,
7:57
we see that there are different ways of looking at things. I would like to use this imagery as a way to perhaps stimulate an introduction to this discussion, which is to try to look at cities with new perspectives, and I think that each of the panelists here are in their own right, known nationally and internationally for creative thinking and they've taken different angles on the urban development question, and as you will see, as we go through the questions that I will ask them,
8:27
and that they will create responses to, and they will run into the final seat in the docket. This is our colleague, Andy Reinmann, who sampled this kind of saltation.
8:40
Stopping and starting of traffic, I imagine. Trying to get here without killing yourself. Thanks for doing that. But each of the panelists is creative in their own right, and has taken a very different perspective on studying cities. I hope that becomes quite apparent as we ask questions and the answers to these questions are an exposition of their academic characters, which are all quite different.
9:10
Along the way, in addition to talking about, some of these what we might call, currents in urban science. The big ideas, the big approaches. We're also going to be taking a look at some of the technologies that we use to study urban systems, and hopefully you'll get a quick summary of that, certainly within an hour or so. We're not gonna be able to cover all the details, but I think you'll get a pretty good picture of the ways that we are approaching modern urban science.
9:37
Our four panelists do come from different perspectives and in some sense that's a metaphor, for the kinds of research that's being done in cities right now, which is interdisciplinary in its very nature, and with that introduction, I think we probably could phase the video out, and move to our first question, which will be posed to Deborah Balk, and Deborah, I'm gonna ask the question. Then you can come on up to the podium, and give a sage answer. How about that? Okay.
10:13
First of all, the topic that Deborah's charged with here, exploring in a short 10 minutes or so, is humans as part of the city, and you've heard in the introduction, she's a demographer. The question to be put to her is the following. Maybe statement comes, then the question. The urban built environment is home to more than half the world's population today. I think we tip that 50/50 split in, I think it was 2007 or 2008. A few years, about 10 years ago, and we have an anticipated rise
10:46
to about 2/3's of the global population residing in cities by mid century, by the year 2050. I think it's important to note, that this trend doesn't just happen. It doesn't happen with the snap of a finger, and there are major forces behind, this reshaping of the planet. It's embedded deeply within the resource systems of the planet, but also the social systems. The question to Professor Balk, is how have cities evolved over the past century, and how are urban researchers forecasting
11:19
the evolution across the 21st century domain?
11:24
10 minutes, or less. - Sure. Why not? Just distill the careers of hundreds if not thousands of people in 10 minutes. I'm happy to do that. Thank you, Charlie. I have some really simple slides. I'll get to them at the end. Whenever you want to put them up, they can just stay there, and then they're tiny little animations. - [Woman] Can't hear you. - Okay. All right, there we go. Better? Okay.
11:52
First of all, let me just say that cities have grown.
11:58
If you want to look at the image. The image that I've posed is a satellite view and a census based view of New Delhi, India, a city of slightly less than 20 million people, with a city called Meerut, to the northeast, which is another small city of about a million. We're just gonna leave those there for a little bit. Cities have grown around the world, largely due to what we call natural increase, which is fertility, net of mortality, and migration,
12:35
but some city growth simply occurs by development. That is institute changes in a given place where changes to the landscape and services that transform a locality from being rural or semi-rural or semi-urban to being more urban. These kinds of institute changes happen all the time as well. This is pretty much the same reasons that cities have always grown. City growth itself, what's happening nowadays, is what we've been seeing over the course of a century,
13:10
the part that's new and is probably irreversible, is that now more than 50% of the population of the world lives in cities. This is an unreversible and important change. Today's urbanization is characterized by several things that are different from the past. For one, in the past most of the growth took place in cities in the west and so forth, but the bulk of future population growth, will take place in cities, so all future population growth. The easiest way to think about it is
13:44
future population growth, happening in the cities and towns, of Asia, Africa, and Latin America. Yes, the United States is still a growing country. The growth that happens in the U.S., also happens in cities, but the lion's share of all future population growth will be happening in the cities, of Africa and Asia, and to a lesser extent, Latin America. That's an important difference to what we've seen in century's past. Secondly, much of today's city growth, occurs from internal migration.
14:16
It's not the fraction of the population that's urban, that's sort of a closed system in a sense. It' not closed between countries, but globally, it's closed, but that is migration within countries, and people from other cities and towns contribute to the growth of a particular city. In other words, as we become a mostly urban world, what we need to understand is that some cities will grow and others will decline or remain stable, because cities are trading people.
14:46
Politically, we pay a lot of attention to migration between countries, but in fact the lion's share of migration occurs within countries. This is an important topic, especially in the context of things like climate change, where people are either moving from localities that are increasingly arid, and they can't sustain crops or water resources, to sustain life in rural areas, and therefore maybe the drivers of migration from rural and semi-rural areas, or even small towns to larger cities,
15:21
it's also on the receiving end of something like climate change. Important to know which cities are growing, and which are losing, because some cities are low lying, and have seaward hazards, that are closely related to the climate and increased vulnerabilities due to climate change, or water scarcity and so forth.
15:42
Understanding which cities gain and lose will be an important thing to understand in the future. Today's cities, like the rest of our society, is older, than we've ever seen in the past. That means that cities are very attractive place for young people, for migrants. Cities are younger on average than other places, because they attract young people looking for work. Today's cities are much older than they've ever been in the past, and that has some implications for how we live,
16:14
how we get around, what services we need, and again how we respond to disasters? Some of which may or may not be climate related. Again, another aspect to keep in mind, that today's cities are, and the future cities of the world, will become increasingly older, and another main difference is that today we have mega-cities. In the past 20 years, we've seen the growth of very large cities like India and China alone, each have 50 cities over a million, and in less than 10 years,
16:45
they will each have multiple 20 million person cities, and the numbers of such large cities, which are again, the lion's share of these cities are in Asia, in fact, is historically unprecedented. We have the ingredients to know a lot about urban trends. We know much less about specific cities, as systems of cities, and that's an important direction for today's inquiry to go in, and I think we'll hear a little bit about that from some of my colleagues, but as strange as it sounds,
17:18
one of the reasons demographically, we know so little about this, is because we have not had spatial data, coupled with demographic data, and that's what this picture is here. On the one side, we see 1990, a picture that's derived from Landsat Satellite imagery. Black and white. The black represents built up areas, around New Delhi, and the others on the right hand side, we see the population distribution around New Delhi. If you could just switch to the next, just one switch. Did it switch?
17:49
Okay, so can you go back just a sec? I just want you to flip back and forth. This is 25 years of change in the built up area around New Delhi. It may not look terribly impressive, that is a lot of aerial change, a lot of transformation to the environment. Roughly 3%, according to my estimates, and that's probably an overestimate, of the world's land surface, is settled by urban space.
18:16
You can see that's a pretty large change that we're seeing there. Similarly, fortunately new generations of satellite imagery, that measure built environments or night time lights, can be coupled with census data, which is the other thing that you see there, to tell us something together collectively about urban form, and particularly changes that are within cities, but also on the peri-urban. We used to talk about urban and rural areas. Those days are long gone. It's an urban continuum,
18:48
and especially as places become all urban. As the world becomes much more urban, it's really important to understand the variation or heterogeneity, within urban environments, and understand that entire continuum. To understand and predict the future, we actually need time series data. We need to know something between 1990 and 2000, 2010, and so forth, to be able to make good predictions about the future, and we have never in the past had a spatial prediction of urban populations.
19:16
These are the ingredients with which we can do it. Satellite data can't tell us everything though, so that's what you see on the other side, which is showing population distribution, but even if we know something about population distribution, I would argue that's not enough either, because one of the things we know, the richness of our urban places, and also fostering demographic change. Demographic change has come about for many reasons. One is because around the world,
19:41
people have become more educated. If you can toggle one more time. One more.
19:49
That one. That shows the proportion of the population, these are illiteracy rates. It has become very pale in the urban areas. Cities tend to be much more educated, but unlike the map of the population distribution which couples the built up area,
20:11
the education fabric is much more checkered. It's a nuanced approach that requires coupling information not only on where people are but who is where, and understanding many aspects of disadvantage. Some of which are conveyed by living in an urban area. Some of which are being in a peri-urban area, and some are out in rural areas, and understanding the connections between all of these. Using these spatial frameworks
20:39
allow us to couple information in a way that's important for understanding vulnerabilities at large, and that's what an approach like this, sets the stage for.
20:51
- Thank you. (audience applause)
20:57
I would like a quick follow up question if I might. The style of development. Can we go back to the last slide? Clearly, we see that there are changes happening from an aerial view. We look down at the sea, we see that spatially it is changing. I wonder if you could comment on the how should we say it? The physiognomy of the city? Are the cities getting more dispersed? Or are they getting taller? Are they doing both? And what might be the implication, if I'm not putting you too much on the spot,
21:32
in terms of the energy security questions? For example, if cities are spreading laterally, clearly you have to have transportation systems, that lock you into perhaps individually owned cars, or different kinds of mass transit, if you were going to go in that particular direction. Could you make a statement about whether cities are growing taller, or are they just spreading, or it a little both?
22:02
- Yeah, that's actually a hard systematic question to answer, because the beautiful data that I'm showing on the horizontal changes, the bird's eye view. That shows us change over time. We don't have a similar vertical change system to look at cities as they're growing up. I'm involved in some research that does that, and there are others out there, who do look at particular cities, and we know for example, some of those very large cities that I mentioned growing in Asia,
22:39
many of them are really growing. They're growing maybe more high and more tall than they are spreading out. Lots of cities grow. Cities grow in different ways, and we here in the U.S., maybe somebody in the room has been to or once lived in Atlanta, which is a flat sprawling city, that is not very tall at all, as opposed to a nice compact city like New York, and I would certainly, I think most of the evidence has been in not by the research I do, but by others that compact cities
23:13
do contribute to efficiencies of scale, both in transportation and in energy usage,
23:23
and there is other research that says most cities are not de-densifying. A few cities, cities like Detroit, who have lost population and economic sectors,
23:38
they have had infill of green space, where they used to have housing and skyscrapers.
23:45
For the most part, the trend is for cities both to grow up and out. Some at the same time. Our measures of out are way better than our measures of up. I haven't shown a picture of night time lights, but those are another data source. That's Earth observing satellite. That's fantastic. Again, it doesn't measure the up, but it does measure economic output, and it could be coupled with these other data sources to tell us something about efficiencies that we see in place,
24:15
and we know something about the density of places, and the association of density with something like night time lights,
24:25
which acts as a nice proxy for energies, as well as economic development, which I should suggest is double edged sword. I'll leave it at that, and let others comment on. I'm sure others have much to contribute to that provocative question, Charlie. - It is a very provocative question, but we need to go on to Peter Groffman, whose now charged with giving us a very quick overview of how humans are shaping the environment of the city, and it's to be noted that more urban dwellers,
24:57
mean more built environment, as we have seen already. More material and energy flows both into and out of the cities. The questions are, there are two questions. How do humans who are densely packed into urban environments, change those environments? How do urban settings differ from their natural ecosystem counterparts?
25:29
- I'll put this question to you all. Are we better off living in Manhattan? Or in the suburbs of New Jersey or Long Island?
25:40
I'll constrain the question, because there are any ways, but in terms of our environmental impact, as a human do I have more environmental impact if I live in an apartment in Manhattan, or if I live in a nice suburb out in New Jersey or Long Island? How many people think my impact is higher in the city? A couple. How many people think the impact's higher in the suburbs? Aha! And how many people here live in the city? (audience laughing) This is a classic confounded scientific question.
26:13
How many people own cars?
26:16
See it's much less. Small number, and of the people who own cars, does anybody drive 25,000 miles a year? Nobody. The question of the environmental impact of cities is actually a super complex and very interesting one. Indeed, cities have lots of people. We consume tremendous amounts of energy, when we live in cities. We make lots of sewage. We make lots of air pollution, and in many ways, cities are these black marks, on the landscape, but if you think about it, the per capita input,
26:49
the effect of each individual is much less when they live in a city, than when they live spread out across the landscape, and New York, as Deborah and Charlie both pointed out, is a notable shining star in environmental impacts. Most people in New York City, do not have a car, and if they do have a car, they drive it maybe 5,000 miles a year, where the average American drives maybe 20,000, 25,000 miles a year. That's an incredible difference in terms of impact
27:17
of carbon, smog causing pollutants, toxic metals,
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and all kinds of other pollutants. We oftentimes live in, some of us live in small spaces. Some of us live in very small spaces. Some people live in absurdly small spaces. Very few people that are living in a 6,000 square foot house with six bedrooms and six bathrooms, and not only that, but our small spaces are stacked up on top of each other. If I'm stacked up on the 12th floor of a building, I can take my small space. I can divide it by 12. I am not taking up a lot of space on the Earth.
27:55
I could be eating super expensive imported vegetables from Chile and other places, but they're being distributed in a very efficient way. They're all coming into the city through Hunts Point and they're all distributed, rather than I could have Amazon deliver my blueberries out to my ranch some place out in Montana. It's a lot more expensive. There are some real environmental advantages to cities. First in the per capita impact.
28:23
The other environmental opportunity that cities provide, is since it's so dense, we have the ability to apply advanced technologies to clean up our wastes. We have sewage treatment plants,
28:37
which is a very exotic topic to talk about, but we have some big sewage treatment plants in New York City. We have some really big sewage treatment plants in New York City. We have some of the fanciest sewage treatment plants on the planet, because it's a lot of sewage, and there's a lot of interest in protecting the receiving waters. We can clean the sewage up quite a bit. We can also clean the air up quite a bit. We can have very stringent regulations
29:02
on the fuels that we burn in our apartment buildings. We can have pollutant controls on the apartment buildings, and how has that worked out? Is New York City cleaner now, than it was in 1965?
29:16
It's unbelievably clean. There was a picture in the newspaper last week of a really smoggy week in 1966, and we never see anything like that now. The Hudson was an open sewer. The Gowanus Canal, still not pristine, but it was worse than it is now.
29:34
We have applied that technology to make our cities cleaner and as a result the environments are much cleaner, and so the environmental impact is less, and the effects on human health and wellbeing are also quite impressive. The challenge going forward then, is how do we maximize the environmental opportunities that cities provide, and minimize some of the potential drawbacks, and the way forward in that, is a new type of research that we call, socio-ecological research,
30:02
and this is a great frontier in research, because it causes us to make humans a part of the system. To understand. We've done very well in environmental sciences. We have humans over here doing bad things to ecosystems, and we've learned a lot about human impact on the environment that way. Now if we really want to understand advanced questions like where people live and how they live, and how they perceive things like global environmental change, we have to make humans a part of the system.
30:28
We have to put humans in the box. There are many people we'd like to put in a box, but this is in a conceptual box, to understand how they perceive the environment, what are the things that they value in the environment, and how do their perceptions and values influence their behavior? One way we're going about that, is we spend some time wondering, why do people do what they do? Could I have my slide? One way we've been doing this is we've been studying cities across the country.
30:56
Here's six different cities, and you can see they're very different. They're very distinctive and very different, and they're not! One of the questions we ask is why do all our cities look the same? In particular, is there a picture of Phoenix in there? Phoenix is my favorite one. People move from this part of the country, to Phoenix in the '50s and the '60s because they had allergies and they had asthma. From all the pollen in the air around here, so they moved to Phoenix,
31:21
and what is the first thing they do when they move to Phoenix? They planted maple trees, and cherry trees, and crab-apple trees, and the pollen counts in Phoenix can be super high now. We dug ourselves into this question, and now we ask our question why and this question Charlie asked of Deborah, what is the structure of our cities? Are they sprawling out and why? We're asking the question of why? Does anyone know why people want our cities to look like this? Any ideas?
31:54
That's one. It actually turns out, when you think about it at first, it's seems like, oh yeah cities, this is what suburbs look like, but actually turned out to be very very complex reason. One is that there's pressure from, what we call the political economy, forces us into it. Other people have deep psychological reasons like we were raised in a Savannah. Or humans evolved in the Savannah, and so we need this mixture of trees and grass and open spaces. Others talk about the ability
32:23
to have a little bit of green space, to have a little bit of garden to work in, so there's a whole variety of reasons, and we need to sort that out. We need to sort out why people do what they do, and what are the ecological implications of those choices, and in a place like New York, the real challenge, is yes, young people want to move to cities. The question is how can we keep them in cities? Because their environmental impact is low,
32:47
and the opportunities for cleaning up our wastes are higher, that's the challenge that we face going forward, and it's this real mixture of social science, ecological science, engineering, and political science as well, to put it all together, and it's a very interesting area of science. - Thank you. (audience applause) Any interventions from our panelists?
33:19
- I think we both have questions for you, but I have a quick question which is, you posed the paradigm of New York City
33:28
versus the suburbs around New York City, as if they're contrasting,
33:34
they're mortal enemies, and I would propose that my continuum approach would suggest actually there are lots of synergies between these and maybe we don't fully understand. I think that the farther away you get from a city, you may have, the Montana example, is a little more clear to understand, and I would probably argue that we don't even have the data to really make excellent rigorous estimation between core urban areas and the areas, and dense suburban areas.
34:09
Anybody here who lives in New York, been out to the suburban areas? That's what cities are in a lot of other places, is our suburbs are a lot like a lot of other cities. I just wonder if you could comment on the continuum model, and the continuum of services from an ecosystem perspective, that might be offered from that model. - Yeah, it is a great question. There are two things that you brought up I think that are very important. One is, there's a continuum. In all our urban studies,
34:38
when we compare these different cities, is we look at urban, suburban and exurban. We always do everything by density. There is a continuum, and then there's two way connectivity, between the city and the urban areas, and a lot of environmental analysis has focused on the cities as these big sucking sound in the city, pulling all the resources from the surrounding area. They call it the urban footprint model, or the urban funnel model, as the city's just pulling resources
35:06
our from the rural areas in a connectivity, which it is true, there are lots of resources, flow from rural areas into the city, but lots of resources flow from the city out, and that needs to be recognized as well. Things like money and culture, and manufactured goods. I think the advanced understanding definitely requires a continuum and two way connectivity. I think that's a great point. - I have to pass the baton now to Peter. The second Peter on the docket.
35:39
Peter Marcotullio, whose gonna talk a little bit now about the social forces shaping cities, past, present, and future. Given the growing propensity of humans to settle in urban areas as we've heard from the last two speakers, how ready are we, or I should say are city planners and managers, to cope with the major challenges, as well as the opportunities presented by modern cities? One important lens through which to view this question, is that of the issue of climate change.
36:12
How are cities readying themselves, or not readying themselves, to prepare for the onset, some might call it the onslaught, of climate change? Peter, could you take the stand, and give us your ideas on these issues?
36:31
- Thank you, Charlie. The way I'm gonna approach this question, is to make it even more complex and challenging, as opposed to giving an answer. Let's talk about environmental change in cities,
36:49
and as we heard from the previous two speakers, certainly population is an important driving force for change in cities that forces cities to get bigger, and taller and that kind of thing, and technology goes along with that. We have wastewater treatment plants now. We have subways. We have elevators. We have, et cetera, et cetera, and this is often looked at, as key drivers in changing the urban environment
37:21
but there's also social forces.
37:24
Certainly, we could look at for example,
37:29
something called the urban mortality penalty, and how that has changed over time. - [Woman] Can you speak a little bit louder? - We can look at, can you hear me now? What's called the urban mortality penalty. Do you know what that is? Okay. The urban mortality penalty is the life years you give up when you move to a city, and you say to me, what are you talking about? In the past, if you moved to a city, you lived a shorter life than if you lived in the rural areas. In fact in the U.S. we only
38:08
passed the point where this difference changed,
38:14
at about 1940, I think, or late 1930s,
38:23
where it was at that point, or that point in time, where we actually started to live equal amounts, and then higher. People now in cities live longer, than people in rural areas, and the reasons why that happened is because cities were really dangerous places. They were very environmentally harmful to humans. What changed about cities was the fact that
38:49
we had what's called a sanitary movement. We had pushing of social services,
38:56
in terms of healthcare and these kind of things, and cities became more and more healthy places to live. Now you could look at a lot of different areas in terms of these types of changes, and the social impact on that. In fact, I have a colleague who had developed a model, of environmental change in cities, that I find very very powerful. He calls it the urban environmental transition. That as you look at cities and they grow in wealth, you find these sets of changes that occur.
39:31
First as cities get wealthier,
39:35
the one response that we do is we start to provide access to water supply and sanitation. People start to have access.
39:46
Instead of looking around for water, and walking miles and miles to get water, we decide to pay for the waters to bring it in.
39:56
In many cases. For example, in New York City, it was in the 1830s that finally the city father said look, we're gonna pay for this, no matter how expensive it is, and we started to bring in water from the Croton, and then subsequently we went to the CAT scales. That was certainly after plagues such as yellow fever and fires forced them to do that.
40:19
You have these changes, subsequent. After that we had the rise of things like water pollution and air pollution, until as people mentioned in the 1960s, people stood up and said we don't want this anymore. We want social change, and they put legislation in, and they forced stacks to get higher, to disperse the air, and they brought in sanitation systems, to finally get the filth out into our rivers.
40:50
Now we're at the point where we are putting our waste out
40:55
into the entire planet, and subsequently, changing climate in that regard. There's two dynamics that are very important, in terms of this model that I feel are worth thinking about. The first is that we never solved our problems in cities. We never solved them. What we did was we displaced them, geographically and temporally. As my professor said when I was getting my PhD in geography.
41:29
My soils professor said to me, Peter, the solution to pollution is dilution.
41:35
(audience laughing) What you have to do is dilute. You have to disperse it. You take your smokestack, and you make it higher and higher and higher, and that pushes it out to larger areas and it dilutes the pollution, or you take the waste water, and you put it into the river and the river will dilute it, and that'll solve the problem, and that is the way we have addressed all of our, many of our environmental problems. Subsequently now, or as historians have called it,
42:06
the search for the ultimate sink. We're at a point where, there's no more sinks. We've hit the planetary boundary with this, and we can't find another place. Although, now we're talking about maybe there's another planet out there that kind of looks like us. I know that people are thinking about using the resources there. That's how things occurred in the past, but dynamics change over time. I'm sorry, I missed one point. That was the one thing. We never solved the problem.
42:36
The other thing that you have to remember is that in our history the solutions at one point in time became the problems in the next generation, or a future point. For example, my favorite example is something that Joel Tarr and Martin Melosi always talk about. The car, the automobile was a health solution.
42:58
The health problem were horses.
43:03
The urine and the feces and the dead horses. There were tens of thousands of horses in New York City, and they would die and they would just go to the bathroom right where they're at. You're sitting there. It created a problem. The maneur, during the summer would pulverize, and it would get into the atmosphere. It must have been horrible. In fact, and then what would you do with all those dead horses? We threw them in what we call Dead Horse Bay which is now Jamaica Bay. (audience laughing)
43:33
When the automobile came around, it was the health engineers that said, wow, this doesn't have any emissions. This is a solution, and they were prominent in promoting in this city, by the way, the adoption of cars. They didn't realize that subsequently these cars would lead to further problems down the road, and there's many other examples that we can talk about, but that is one of my favorite. You have this solution. A problem, solution, problem, which created a sequential landscape,
44:12
where we have a set of problems, and then we solve them, and then subsequently another set of problems arise, and then we solve them, et cetera, until we're where we're at, where we have yet to be able to solve our consumption and our emissions problems. That said, what's happening as Deborah pointed out, is we're seeing rapid urbanization in the developing world, and because of dynamics called globalization, that's not.
44:39
The same sequential problems, and solutions, and problems, and solutions, are not occurring there. In fact, what's actually happening there is that when you walk into any developing world city and I'm sure many of you have been there, you'll see the 18th century city, you'll see the 19th century city, you'll see the 20th century city, and the 21st century city, within the boundaries of that place. You'll see somebody's driving a 2017 BMW,
45:07
and five miles out you'll see a guy, with an oxen and a wooden plow.
45:14
5,000 year old technology, and everything in between. Cities in the developing world are dealing with much more complex problems in a way, than we had in our history.
45:28
They are not going through the same pathway as we went through, as we experienced. They're experiencing something different. Now what makes this all the more complex, is that as I mentioned, we're at the end of our search for the ultimate sink, and we're facing. We have grown so large, and grown so powerful, in terms of our ability to consume items, consume materials, consume elements, and our ability to emit waste, that we're actually changing the climate, arguably.
46:07
How does this affect all of us? Let's just take one example of, temperature.
46:15
Now I want to take a step back about predictions. No one really can predict anything, including the future, but we're gonna take a try at it. With that hesitation,
46:30
if we use what's available in terms of the models that have been worked with, and we start to ask, let's just look at temperature, and cities, and ask the question, who is going to be living in warm places? You can put the slide up now. Thanks Jeff. You could see two slides there. On your right hand side, there's a slide that gives you the curves based upon what's called the IPCC,
47:06
RCPs which is the concentration pathways
47:11
of all the greenhouse gasses. There's three of them there, and that shows you, what the average three hottest months of the year
47:23
are going to be in 31,500 cities, globally.
47:28
You could see in 2000, temperatures were below 24 degrees C, for the three hottest months. That's about 76 degrees. For the three hottest months. It depends on the pathway you're on. The blue one is the highest. That's called RCP 8.5. That's the representation of a concentration pathway that will create 8.5 watts per meter squared
47:57
higher than the industrial level,
48:01
and there you're gonna have temperatures on average, this is a global average, of about up to 29 degrees, which will be about 84 degrees Fahrenheit, and at the lowest end we see RCP 4.5,
48:16
which is gonna be les then 27 or 26.5, which is going to be about 79 degrees Fahrenheit. We're gonna see a significant increase in warm temperatures. If you look on the other side of that, the left. The right side, I'm sorry. The left and the right. The right side of that chart. What you'll see is what I took is one pathway which would be the conservative one, which is 4.5, and I asked, given a certain population size, how many people are going to be living in very warm places?
48:51
Let me just tell you that if you're above 35 degrees C, that's on average, a monthly average, for three months, of 95 degrees. How hot does it get in New York City? On average? In July and August? What's our average temperature?
49:12
It's less than 80.
49:14
July and August, about 78 degrees.
49:18
95 degrees for three months in a row.
49:23
How many people? A lot. Half a billion. All things equal. This is just throwing population at a map. If this occurs, people there,
49:40
I don't know what they're going to do. They'll either have to use much more energy, because they're gonna have to cool themselves. They're going to get very sick, because it's gonna be that hot, or they're gonna move. Do you know how many people are in Syria, or were in Syria, before the war?
50:03
About 25 million.
50:06
This is half a billion people. That to me, when we first did this, these are only preliminary. When we first did this, we found this really really significant. Of course, we don't know what's gonna happen, but I'm just gonna leave it at that, in terms of do planners know, and how are we working towards some of these solutions? I hesitate to answer that.
50:33
Thank you.
50:35
(audience applause)
50:41
- Now you know why he's earned the nickname, Mr. Sunshine. (audience laughing) Hopefully you'll be able to get us on to a more positive track here, Andy. Our next speaker is Andy Reinmann, whose our newest faculty member at the Advanced Science Research Center, CUNY facility. Andrew's gonna be talking about how we measure cities. All of the many changes we've heard about today, require some type of assessment. How do we actually put our finger on the pulse of what's going on in cities?
51:17
Whether we're looking at social or demographic changes. Whether we're looking at the biogeophysics of the these systems or the architecture, as it were, and the question to Andy is, are scientists able to keep pace with the changes that are occurring in the modern 21st century city? That is, can they monitor what's going on? Interpret this very very rapid evolution? And what kinds of tools are available to allow us to stay a little bit faster than that bow wave that we see.
51:51
That large urban boat that's moving through the water is generating. Andy, could you take on that complicated question for us?
52:04
- I misunderstood a little bit. I thought the panel was you give me the answer, and then I ask you the question, but I'll take a stab at it. First, when Deborah spoke a little bit about urban demographics and how things are changing, she mentioned that 3% of the world's land area, is occupied by cities or developed area. Quick show of hands. Who think that's a lot of space, from an ecological perspective? Is that en ecologically large amount of space? One person. That's it? Two.
52:37
All right, three people. I'm gonna let my bias as an ecologist and a forest ecologist shine through here a little bit, and what if I were to tell you, that 3% of the land area on Earth, is equivalent to all of the temperate forest that exists. That's in the U.S., all of the forest that's east of the Mississippi River, and all of the forests that you would find in Europe, and these are heavily studied ecosystems. We know a whole lot about them, and generally we think they're pretty important,
53:04
but if you were take all of the cities in the world, and collapse them together into one space, it would occupy that same amount of space. Let me ask that question again. Who thinks that 3% of the land area is an ecologically meaningful amount of land to occupy by cities? All right, great. Good, you all passed. Can you show my slide? Just the first one. Great. As an ecologist, I get really excited to go out and measure things, and initially I was trained as a forest ecologist,
53:36
so I would go out to the forest, and I'd want to do things like, measure the trees. See how big they are. How much biomasses they are. How much carbon is being stored in the forest? Think about some of the aspects of the vertical structure of the forest, and what the microclimate of the forest might be, and then a few years ago, I started getting into studying urban systems, and at first I was really excited about this, because all right, I get to jump into a new novel system,
54:00
and then when I started looking at urban systems, I had to sit there and start scratching my head, and this image that I'm showing here of greater Boston, New York's smaller sibling to the north, I think really exemplifies why measuring cities is such a head scratcher,
54:18
because they're so complex, and there's so much heterogeneity built into them. When we think about a forested landscape, we think about a large expanse of trees, and it's all one land cover type, but when we create cities, effectively, what we do, is we fragment the native landscape, native habitats, and what we're left with, is this complex, heterogeneous mosaic of a landscape that's a combination of let's say native forests, and a variety of different habitats that we create.
54:47
This may be the Savannahs, that Peter Groffman was talking about earlier along our streets, or I think I heard Peter Groffman also talk about lawns as being urban grasslands, and I really love that term. It makes them feel a little bit more noble, than just our backyards. We have these urban grasslands, and these Savannahs, and our patches of urban forest, and then in addition to that, and sort of mixed into all of this, are all these impervious surfaces. These are things like roads
55:15
and buildings and residential areas, and everything that goes into them, and our built infrastructure has a variety of different sizes and heights and colors, and it's like we take all these ecosystems, and we throw them into a blender, and then we spill it out on to the landscape, and that's our urban landscape. How do measure things in that sort of environment? One way that I think is a pretty amazing way to start thinking about how we measure urban landscapes,
55:47
and it allows us to do this at a global scale, is using satellites. Satellites sit up 36,000 kilometers above the Earth's surface, and they're constantly flying around, taking measurements of the ground, and they can tell us some really really amazing things. If you can show my next slide. These are also images of the same greater Boston area, except now I'm showing data that we derived from satellites, and one of the things that I think is really incredible, is that from 36,000 kilometers
56:16
above the Earth's surface, we can measure things at a 30 meter resolution, on the Earth's surface, which is pretty amazing, especially when you're trying to categorize these really complex heterogeneous landscapes. This is, I don't want to say a simple way, because a lot of people have made their careers of figuring out how to do this, and build these instruments, and the algorithms that go into getting information from them, but once all that is taken care of, as an ecologist I can go in,
56:42
as a relatively simple way of starting to characterize what the biophysical composition of these urban ecosystems looks like, and so in this figure, on the upper left, showing the distribution of impervious surface area. The darker the red, there's more impervious surface. The lighter the red, there's less. One the top right, I'm showing spatial variability, in Albedo. Raise your hand if you've heard the term Albedo before? This half of the room mostly has. For you guys, Albedo is essentially
57:12
the amount of incoming solar radiation that gets reflected back into the atmosphere, and this is really important because darker surfaces absorb more incoming solar radiation, and this plays a really important role in driving the urban heat island effect. Raise your hand if you've heard of the urban heat island effect before? Okay. Most people. That's where we're effectively changing the materials on the landscape, and the color of the landscape of cities, and that is usually making them warmer,
57:40
and a big part of that is this Albedo component, and you can see it's not uniform across the city. There's a lot of different colors there. On the bottom left, we're showing tree cover, and lots of people think of cities as being devoid of any vegetation, and what we find is that's not true. There's a lot of spatial heterogeneity in the amount of tree cover as well, and that's another thing we can learn from satellite, and then thinking about the human environment, what humans are exposed to.
58:09
In the bottom right, I'm showing land surface temperature. This is what you would feel if you were to put your hand on the ground, and living in the city you know on a really hot summer day, if you touch dark pavement it's gonna be fairly uncomfortable, relative to touching a patch of grass, and there's a lot of heterogeneity in what the surface temperature is like. Here's the tip of the iceberg, of some of the ways that we can measure cities, from way high up in the sky.
58:34
Other things that we can get from satellites, is we can learn things about processes. What plants are doing? Again, at this 30 meter resolution. We can look at tree phenology. Is that a new word for you? Phenology? Phenology is essentially the timing of natural events, and from a tree's perspective, we could think of this as the time that trees put on leaves in the spring, and the time that they lose their leaves in the fall, and the whole time in between is the length of the growing season.
58:58
I could have shown another map showing growing season length, and you would see a similar amount of spatial heterogeneity, even in this small area. Maybe that area is 15 by 15 kilometers, or 20 by 20 kilometers. In that small of an area, you can see differences of weeks in the length of the growing season, from a tree's perspective, and the instruments that we use on satellites, is constantly evolving, and so as these instruments evolve, and we send up new satellites,
59:26
that's gonna further our capacity to better characterize cities, and what's nice about satellites is we can do this all over the world, without having to physically go places.
59:41
Another thing that we can measure from satellites, is the amount of carbon dioxide in the atmosphere, at any point on the Earth, and there's a recent satellite that's been. It was launched a couple of years ago, and it measures CO2 all over the world, and this is really important because even though cities occupy only 3% of the world's land area, they're responsible for the overwhelming majority of all of our greenhouse gas emissions. Being able to measure this remotely,
1:00:05
is a wonderful new capacity that we have, for characterizing more about what cities are doing. Other things that we can do to start to measure cities, is we can move a little bit closer to the Earth, and this is where I'm a little bit more comfortable, because I'm used to going out and measuring a tree and figuring out what it's doing, and if we want to quantify the amount of biomass, and the amount of carbon being stored by vegetation in cities, there's some obstacles to doing that.
1:00:36
In a forest, I could fairly easily bring out a crew of people. We could cut down trees a variety of different sizes, weigh the trees, and then develop some relationship, between the diameter of the tree, and how much biomass is there, and then measure a whole bunch of other trees. Just the diameter and estimate what the biomass is. In cities there aren't too many trees. How many of you would be thrilled to see me out on the street cutting down all the street trees to figure
1:00:59
out how much biomass was there? Science is great, but we don't want to lose what little vegetation we have, and so this is problematic in cities, also because the growth form that trees take in cities, is vastly different than what the same tree species would have in a forest. In a forest they grow tall. They grow straight. In a city, they're shorter and they spread out. How do we overcome something like that? Well there are these new laser technologies, that you can attach to an airplane
1:01:26
or to a car and drive it around, or to a tripod, and I can take this out to different places in a city, and effectively get these 3D images of buildings, and I can quantify in three dimensions, what the built infrastructure looks like in the city, or I can take this to a tree, and then quantify the volume of the tree. If I have the volume of the tree, now it's fairly easy then for me to quantify what the biomass is. There's a lot of people that are working pretty hard at
1:01:56
how to take advantage of these new technologies and develop these new sorts of applications for them. Then there's hyper spectral cameras that we can use, and these are fancy cameras, that again we can attach to the tops of buildings, or to tripods or cars or airplanes, and it's measuring all sorts of light wavelengths, that are coming off of vegetation, and this can tell us a lot about how productive that vegetation is. Without ever having to pluck a leaf off of a tree,
1:02:24
or take a tree core from a tree and measure how fast it's growing. We can get a lot of information from these sorts of cameras. I think the key to measuring things in urban ecosystems, is to be able to figure out ways to do this non destructively, and one additional way that we can think about measuring cities, is through sensor networks. There's all sorts of new sensors available, that have been developed in the last 10 years, 15 years, that we can deploy all over the city,
1:02:52
and even put them on our trains to measure things in a range of different spatial locations, and these things can stay there, and measure these things over time and these things that I'm talking about are air quality and micro-climate, and we can figure out what's the spatial heterogeneity in those aspects of urban ecosystems? This is important when we start thinking about human health and policy implications that we might want to take advantage of
1:03:20
to improve the condition of humans living in cities. That's a spattering.
1:03:26
Touching upon a bunch of different ways that we can think about measuring cities. One last point along those lines that I want to bring up, is oftentimes in ecology, we hear about keystone species. Has anyone heard of that term, keystone species before? These are things like beavers or woodpeckers, that would modify their environment in some way that creates some new habitat, that other organisms in that ecosystem rely on, and in cities we can think of humans as being that keystone species.
1:03:59
Effectively, cities don't exist without us, and for all the negative consequences
1:04:06
on ecology that building a city might have, there's a whole suite of new organisms that come in and live there and take advantage of these new ecosystems, and maybe we want to think about how do we quantify and measure and characterize the environment around this keystone species, humans, and there's been a few interesting sensors, and some others that I think are on the horizon that are called wearable sensors. These are things you can put on your wrist,
1:04:35
or you can, your iPhone, your smartphone, can be used as these wearable sensors, and effectively what they'll do is they'll geolocate where you are and make measurements as you go about your day, on things like what the micro-climate's like where you are, what the temperature is, what the relative humidity is, different aspects of air quality, and it will track you throughout the day and this is a really important thing, because if you have a city like New York
1:05:02
where you have nine million people, let's say we had an infinite budget and we can outfit every one in the city with these sensors, then we can figure out which people are experiencing higher exposure to different environmental stressors. Whether it be from a climate condition, or air pollution, or something along those lines. Not only does it help us to figure out answers to human health issues, but it also helps us to learn a whole lot more, about spatial heterogeneity,
1:05:30
and the characteristics of urban ecosystems. I will finish with that, and just ask you all when you're going home tonight, your homework assignment is to be that keystone species, and think about all of the different environments that you're going through. The different micro-habitats that you're going through, between now and when you get home, and what the temperature's like, and what do you think the air quality is like, and what's around you? That's your urban ecosystem.
1:05:57
(audience applause)
1:06:03
- Taking a close look at the time, and we're approaching the end of the forum. What I'd like to do is ask are there any questions in the audience that you would like to put to our panelists here? You certainly have had an earful and an eyeful in just about an hour. Decades of research have been summarized in about 60 minutes here. Yes. - [Man] How are you defining a city, and an urban area? How are you defining city and urban area? - Could you show me that slide I gave you?
1:06:37
I grew up in New York City. So that's my view of what a city is. (audience laughing) Clearly, I'm hoping that the notions of the fact that cities are dynamic places, that they don't sit in isolation of each other, they're interconnected through energy and material flows, social flows. Deborah's probably the best in terms of giving a very specific definition of urban areas, given that she's a demographer, and of course, cities are where people live. Do you want to give us a working definition,
1:07:14
Deborah, of a city? - Sure. You won't be surprised to know that countries around the world decide what's urban based on many different criteria. For example, some countries, like India uses it. A simpler example, some places just say,
1:07:34
all populated settlements above X thousand persons is urban. That's a very simple population characteristic rule that's used. Other places use something more complicated, like number of people in a place, and 75% or more of the population is not engaged in an agriculture. Something like that. A functional definition. Every country in the world has a definition like this. There are many different criteria that are used in them. I would say about 2/3's of them
1:08:08
are population or population density based, and we have one such that's something like that in the United States as well. For example, every single census block, which is there are nine million of them for the United States, they're the smallest enumerator area, of the U.S. census is defined as either urban or rural, and you can tie them all together, and you can make a map as I have done, to show all the small places in the U.S., and the large connectivity of those places
1:08:37
that are classified as urban, by the U.S. Census definition. Now I frankly don't think that's adequate. We then take satellite data and we use measures of the built environment, and the map that I had shown earlier
1:08:52
was a 50% threshold of the built environment that you could see in the dark. The dark grays and black hues. That's roughly where 50% of a given locality can be observed, of a given 30 meter pixel, can be identified as built up, and built up is something like,
1:09:14
not vegetated, frankly.
1:09:17
Something that's measured through satellite imagery. Those are two working definitions that allow you to define urban that are pretty simple and straightforward. The eye is in the beholder's view.
1:09:32
You might think, and there is a long debate,
1:09:38
for 50 years on what is urban, and it has changed a lot. I would argue that debate can continue. It's not an unhealthy debate, but it's useful to have a few metrics that can be compared across place as well as having that debate which allows for a lot of variation that's place specific. That probably didn't answer your question, but that's the way the scientific community would answer it. - [Charles] The back of the room.
1:10:11
- [Man] Cities are promoted as being efficient way of living. One very short question. I don't know if it's journalistic one. How many billions can the Earth sustain if we live in these so called efficient dense packed cooperative city living, compared to the current models? That's number one. Number two, you mentioned data. City produced data, also we as individuals will produce many data, and you actually invited us to keep collecting more data on city lifestyle. Who owns the data,
1:10:50
and is there any talk about this intellectual commons which now is being produced by this cooperative beehive, that the city's become? That's it, thank you.
1:11:04
- [Charles] Who would like to take that one?
1:11:10
- I'll take a shot at the first one. The first question is very very difficult to answer, and it's a question that people have debated about for many many many years. People have always worried that there's too many people. Where it's gonna go up, up, up, up, up, and there will be a crash, and yet the population keeps growing more and more, and we haven't had those crashes. Thomas Malthus, when was Malthus? 18? - 17. - He was the first one that predicted that
1:11:39
we'd run out of food and everyone would die, and then there were predictions that we were gonna be overrun by horse maneur, as Peter talked about. Then in the '90s Paul Ehrlich wrote The Population Bomb. No, in the '70s he wrote The Population Bomb. Said by the 1990s there was gonna be large scale social disruption and violence in the streets because the population was, and the Mets won the world series. Everything was good. (audience laughing) This is a great challenge, and no one really knows
1:12:06
what the carrying capacity of the Earth is, or the carrying capacity of a city is, but the effort to answer that question, it strengthens us,
1:12:16
but the answer is not straight forward. - I should add to that, that there's a group that looks at the so called ecological footprint of humanity, and they believe that we're at the point now where we're at about 1.2 or 1.3 Earth's worth of resources, to sustain humanity, and if we don't do business differently, we'll be at about 3.5 Earth's resource bounties
1:12:42
worth of consumption by the year 2050. That's a highly debated set of estimates,
1:12:50
but nonetheless there are trajectories that continue to go up in terms of the consumption of resources, and though we've become more efficient, there are more of us, and we have aspirations for wealth, and I do water research, and I can tell you that the growth of the middle class, the global middle class, which we certainly understand is necessary to eradicate poverty, will have enormous stresses on the water system of the planet, and to the point where that could be
1:13:19
a real constraint on future development. - I'm glad this was a simple question. Can I supplement?
1:13:29
This question about city efficiency is actually still a question. There's a lot of people that, they look at what happens with various
1:13:41
factors as cities grow in size?
1:13:45
Is the relationship sublinear or superlinear?
1:13:50
If it's sublinear that means that they're getting more efficient as they grow in size. You can see this in some aspects, particularly infrastructure. Larger cities have less infrastructure per capita, and things get delivered more efficiently, but it's not like that for all factors. There are some things in cities that are superlinear.
1:14:16
Crime.
1:14:18
Per capita. Per capita crime is higher in cities than in less dense places, and I think these people at, West and Bettencourt, they've done a lot of work on this, and what they suggested was that cities are like animals, and as animals get larger, their metabolisms get more efficient, so they have a sublinear relationship that way,
1:14:50
but they fail to show that for all aspects of cities. There's a lot going on here.
1:14:59
- Before I let Andy answer the other question that you asked, I just want to let everybody in this room know that you have observed something very special here, because when you asked the question about carrying capacity, it's usually my role as the social scientist in the room to be the naysayer, to say well in fact, there is no agreed upon limit as carrying capacity, and usually there's a large debate between environmental scientists and social scientists over this particular point.
1:15:29
For the record you have seen an eloquent, nuanced, and quite in my opinion, very accurate assessment of the literature that was largely contributed to by early economists and social scientists on the point of carrying capacity and the fact is is that, over time technology has always allowed for higher carrying capacities to exist, and there honestly is no reason to believe that that will not continue in today's day and age. We don't have any reason to believe it won't exist.
1:15:58
The only thing that's substantially different in today's world, than in the past, is this global, what we call in economics, largely as an externality known as climate change, and that's kind of unprecedented style problem. Previous generations have had pollution in a given city, but now we have a global pollution that's on the order of things we haven't seen before,
1:16:22
but even that held this idea that
1:16:27
there is a single carrying capacity is debated and there's no agreement on it, but history tells us technology usually provides at least a medium term solution to future population growth, and by the way the population will stabilize as well. It's not a population issue as Charlie pointed out. It's whose consuming what?
1:16:52
- The data question is a little bit more straight forward. I can maybe be a little bit more brief about it. I think there's a couple different aspects to it. One is data that is being collected in some sort of stationary location, or if you were to attach something to a train, there aren't really the privacy issues that go along with that, and those data could be owned by whoever was conducting that research, whether it be a municipality, or a university.
1:17:18
In a lot of cases, if it's coming from some sort of publicly funded institution like the government, at some point at least some subset of this data would have to be made publicly available. That depends on the granting agency. I think where it's a little bit more complicated, and more sensitive, is if you were to outfit people with sensors, then what happens to those data? On one hand, we're all walking around with sensors now. Google is tracking everything that you do with your phones.
1:17:45
When you use Google maps and you look to see where there's traffic, it's calculating that based on where phones are moving essentially, and those data in some ways are anonymous and maybe you could take a similar approach if you were to start outfitting people with sensors. Currently the scale at which these wearable sensors might be used is on the scale of one small study where all the participants involved, there's some sort of anonymity that goes along with those data,
1:18:15
but moving forward if we were really thinking about doing this at any broad scale, that's a discussion that would definitely, we would need to have, because you're tracking people's movement, but you're also tracking things about the environment where they're moving and maybe this a conversation that is similar to what we need to have about cell phones tracking us everywhere we go as well. I don't have a good answer of what the solution to that is but it's certainly something to think about.
1:18:42
There's benefits to us all having sensors, and collecting data as we go everywhere, but there's certainly privacy drawbacks. No concrete answer, but it's something that needs to be part of the discussion moving forward. - [Charles] Let's take one last question, because I see we're a little bit over time. Would you like to ask the question?
1:19:06
- [Woman] I would like to talk about these urban area versus suburbs.
1:19:17
You said about, and I live in the city,
1:19:22
and I don't have car. I don't even drive a car. I cannot drive a car. I would love to get on this American train that I should not be blamed. It's not my fault, but you see, of course, cars used in these areas,
1:19:41
where a lot much more green areas,
1:19:48
that reduce this impact,
1:19:52
but migration is why we still don't discuss question of public transportation, in these areas. Why we don't discuss simple questions? For examples, all these sensors, all the city lights, all these modern technology,
1:20:13
has biggest impact and we don't discuss it. We would like more talked about,
1:20:21
positive collections of data,
1:20:24
is something like this, but we don't discuss, what kind of impact of this industry has on our environment.
1:20:37
- I can say just a little bit about the public transportation question, and question of suburbs, and you see it in New York City,
1:20:47
the public transportation system in the '70s was not very attractive,
1:20:54
and they made investments to make it better, cleaner, and more efficient, and the ridership exploded. It just exploded, and it helped the population of the city grow, and it's everything that you suggest, that if you make investments in public transportation. If you make investments in parks, and in other ecological amenities in cities then the cities grow, and the environmental efficiencies increase. We need to demonstrate that, and then help people.
1:21:28
As scientists all we can do is, we can do science. We can produce results. We can help society make decisions, based on that science, and one set of decisions might be to make investments that build these environmental efficiencies in cities, and that's a big part of what we do in urban ecology.
1:21:51
- [Charles] Any other footnote to that? Okay. Let me call to close the interesting forum, and I'd like to particularly thank our four panelists. Peter Groffman, Peter Marcotullio, Deborah Balk, and Andrew Reinmann. (audience applause) Thanks.
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