Category Archives: Cities

Cities, Inequality, Reorganization, Visualization, Vulnerability

Haiti a year after the quake

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The strong 2010 Haiti earthquake had its epicentre near Port-au-Prince, Haiti’s capital. It killed about 230,000 people, injured another 300,000, and made another 1,000,000 homeless a huge impact on a country of 10 million. The earthquake caused an estimated $10 billion worth of damage, more than Haiti’s annual GDP, a huge impact on a small, poor country.

The Big Picture photoblog has a great collection of photos from a year after the quake:

Soccer players from Haiti's Zaryen team (in blue) and the national amputee team fight for the ball during a friendly match at the national stadium in Port-au-Prince January 10, 2011. Sprinting on their crutches at breakneck speed, the young soccer players who lost legs in Haiti's earthquake last year project a symbol of hope and resilience in a land where so much is broken. (REUTERS/Kena Betancur) #

New York Times has a collection of aerial photos that show Haiti before the quake, immediately after, and now.  They also have the stories of six Haitians in the year after the quake.

NPR has a collection of stories on the post-quake recovery.

Michael K. Lindell writes in Nature Geoscience on the need for earthquake resilient buildings. He writes:

Usually, the poorest suffer the most in disasters that hit developing countries, but this may not have been so in Haiti. The lowest quality housing experienced less damage than many higher quality structures. Specifically, shanty housing made of mixed wood and corrugated metal fared well, as did concrete masonry unit structures made of concrete blocks and corrugated metal roofs. These inexpensive shacks probably had a very low incidence of failure because they are such light structures. At the other extreme, the most expensive seismically designed structures also seem to have performed well, but for quite different reasons. Although they were heavier, they had designs that avoided well-known problems, and the materials used in building were of adequate quality and quantity. It seems to have been the moderately expensive structures, built with concrete columns and slabs, that were reinforced, but concrete block walls that were not. Such structures frequently experienced severe damage or collapse because their builders cut costs with inadequate designs, materials and construction methods.

The relationship between building cost and seismic safety thus seems to be not just non-linear, but non-monotonic. That is, people can spend their way into hazard vulnerability, not just out of it. To avoid this problem, three main requirements must be met. First, earthquake risk maps are needed to identify the areas where seismic-resistant construction is required. Second, building codes must then be adopted, implemented and enforced. Finally, insurance is required to fund rebuilding after an earthquake in which building codes have saved lives but not buildings.

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Today, mitigation of earthquake hazards is not held back primarily by a lack of engineering solutions: architects had access to manuals for seismic-resistant design for nearly 20 years at the time of the Haiti earthquake. But substantial further research is needed to examine how people can be convinced to make use of existing options for achieving physical and financial safety — especially in areas, such as the Central United States New Madrid seismic zone, that have earthquake recurrence intervals of hundreds of years. Implementing risk-management strategies for coping with such low-probability, high-consequence events will require innovative public/private partnerships.

Ultimately, even the poorest countries must regard building codes as necessities, not luxuries. Moreover, even relatively wealthy countries need to develop more effective strategies for managing seismic risks. This will require collaboration among earth scientists, social scientists, earthquake engineers and urban planners.

Adaptation, Cities, Ecosystem services, Ideas, Networks, Tools

Scale-crossing brokers: new theoretical tools to analyze adaptive capacity

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Social network structure for ecosystem governance.

Social network structure matters for adaptive capacity. A key position are 'scale-crossing brokers' that link actors interacting with ecosystem processes at different ecological scales.

Together with colleagues from Stockholm University we have just published an article in Ecology and Society called:

Scale-crossing brokers and network governance of urban ecosystem services: the case of Stockholm

Henrik Ernstson, Stephan Barthel, Erik Andersson and Sara T. Borgström, Ecology and Society 2010: 15 (4), 28.

The article synthesizes empirical studies of urban ecological management in Stockholm. However, it also contributes to the theoretical discussions on adaptive governance of social-ecological systems (e.g. special issue in Global Environmental Change, Folke et al. 2005, Duit and Galaz, 2008). As such, the article is of interest for studies in marine, forest and agricultural systems.

Here I present some key theoretical ideas. (See also blog at Stockholm Resilience Centre.).

Framework for assessing adaptive capacity – linking ecological processess and social network structure

The article builds a theoretical framework that links ecological processes to social network structures to assess the adaptive capacity of ecosystem governance. In effect, the article pushes present theorizations in at least three aspects: 1) spatial complexity, 2) the role of social network structure, and 3) how to handle cross-scale interactions.

1) Spatial complexity

First, it builds a framework to more explicitly account for spatial complexity (and thus the complexity of the ‘resource’ in question). This is primarily done through empirically focus on the ecological processes of seed-dispersal and pollination, which are processes important for the re-generation and resilience of local ecosystems in the fragmented urban landscape of Stockholm.

2) Social network structure as intermediate variable

Second, the paper ‘looks’ beyond individual actors and their direct ties to others (often the case in the literature on for instance ‘bridging organizations’). Instead, actors that interact with ecological processes are seen as embedded in patterns of communication and social relations. This means that the paper acknowledges ‘social network structure’ and how this intermediate variable (not individual, not institution) mediates the agency of single actors, and the performance of the whole network to respond to change.

To capture social dynamics we take the idea from sociology that, just as ecological patches are part of greater scale patterns, social actors are part of emergent social network structures that constrain and shape social dynamics (Wasserman and Faust 1994). […] social network patterns are consequently an outcome of localized interactions between pairs of actors, and no actor can fully control the emergent structure. [This] allows for human agency, but an agency constrained and mediated through the network structure itself (Emirbayer and Goodwin 1994).

3) Cross-scale interactions and scale-crossing brokers

Third, the paper pushes the understanding of what it would mean for a set of identifiable actors to handle cross-scale interactions in social-ecological systems. This is done through developing a network model of how certain actor groups engage in ecological processes at different scales through their social practice, and to theorize a key network position called ‘scale-crossing broker’ (building on Burt’s notion of brokers):

Thus, by accounting for the structure of social networks between actor groups, and how they link to ecological scales, our resulting model consists of actor groups interacting both with each other and with ecosystem processes at different spatial scales, and at spatially separate sites [see figure at top].

A final central aspect of our model is the network position of scale-crossing broker [which is defined] as a social network position that links otherwise disconnected social actor groups which, through their social practices, interact with ecosystem processes at different ecological (and spatial) scales and at different physical sites.

In relation to the discussion on how governance systems can cope with slow changes on one hand, and rapid changes on the other, our answer indicates that we must look for this in the social network structure that links various actors across scales. In that sense, the scale-crossing broker becomes “a crossroad for possibilities” and could facilitate the “switching” between supporting localized social learning processes (in times of slow change), and centralized collective action (in times of rapid change):

Scale-crossing brokers can be seen as agents for nurturing the emergence of a purposeful social network structure, and for switching between a centralized collective action mode and a decentralized mode of social learning among a diverse set of local autonomous actor groups.

Assessing governance systems

As such, the scale-crossing broker becomes an analytical lens to use when assessing empirical governance systems. Upcoming research should thus aim to measure the extent to which you can find scale-crossing brokers in a particular system. Another such assessment tool lies in our conceptualization of a meso-scale in governance in the form of ‘city-scale green networks’ (see figure below).

In conclusion, and apart from its empirical findings not touched upon in this blog, the paper can be seen as bringing new theoretical ideas on how to discuss and analyze social-ecological complexity and adaptive capacity. For more information see the paper itself, the blog-post at Stockholm Resilience Centre, or my own blog In Rhizomia.

The article is part of a special issue in Ecology and Society on social network analysis and natural resource management.

Governance of complex ecological processes

Fig. 4. The figure demonstrates how one could identify the city scale green networks of pollination and seed dispersal in a particular area of Stockholm (suggested here by using digital mapping and ecological network analysis (cf. Andersson and Bodin 2008)). Note how certain local green areas are shared between the two city scale green networks, which give rise to network overlap (purple areas with bold vertical lines in city scale green network 2). Furthermore, it is suggested that midscale managers can take responsibility for particular city scale green networks. Taken as a whole, the figure demonstrates how particular ecosystem services can be viewed as embedded both in the physical landscape and within social networks of local actor groups (managing local green areas), scale-crossing brokers, and municipal to regional actors.

Cities, Networks

Geoffrey West on Biological and Urban Allometry

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Santa Fe Institute physicist Geoffrey West giving a talk about the allometry (scaling rules) of animals, organizations and cities (his work has been on resilience science before) – based on his great work with ecologists James Brown and Brian Enquist.

In an interview with the Santa Fe Reporter, West was asked “Was studying the networks within organisms what led you to study networks between organisms, ie cities?  West replied:

Exactly. It’s obvious that a city, or even a company, has network structure. Not even at the social level, just at the physical level, a city has roads and gas stations and pipelines, which are networks. But it also has something more abstract and, in some cases, something more sophisticated than in biology. And that is networks of social interactions, which are where things like information and knowledge are being translated.

If you go back to biology, another way of saying it is that—let’s just think of mammals. The fact that the whale is in the ocean and the elephant has a big trunk and the giraffe has a long neck and we walk on two feet and the mouse scurries around, these are all superficial characteristics. And in terms of their functionality, their physiological design, their organization, their life history, the essence of what they are, they’re actually all scaled versions of one another. We are, at some 90 percent level, just a scaled-up mouse. And the question is, is that true of cities? Is New York just a scaled-up San Francisco, which is a scaled-up Boise, which is a scaled-up Santa Fe, even though they look completely different?

So what we did is look at all this data, everything from number of gas stations to length of electrical cables to number of patents they produce to number of police and crimes and spread of AIDS disease and wages, everything you could lay your hands on, and ask, ‘If you look at those functions of city size (population), is there some systematic progression?’ And to our amazement, actually, there is. So, in some average way, Santa Fe is a scaled-down New York City.

Cities, Visualization

Nile Delta at Night

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Nile River Delta at Night from NASA’s EOS image of the day.  They write:

The Nile River and its delta look like a brilliant, long-stemmed flower in this astronaut photograph of the southeastern Mediterranean Sea, as seen from the International Space Station. The Cairo metropolitan area forms a particularly bright base of the flower. The smaller cities and towns within the Nile Delta tend to be hard to see amidst the dense agricultural vegetation during the day. However, these settled areas and the connecting roads between them become clearly visible at night. Likewise, urbanized regions and infrastructure along the Nile River becomes apparent.

Cities

Bhopal 2011: Requiem & Revitalization

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MJ writes about BHOPAL 2011: Requiem & Revitalization an International Students’ Workshop and Symposium, Bhopal, India January 23 – February 04, 2011.  The workshop is organized by the School of Planning & Architecture, New Delhi, modern Asian Architecture Network (mAAN), India and The International Committee for Conservation of Industrial Heritage (TICCIH) India.  More information is available on the conference website.  MJ writes:

Bhopal is known the world over as the city that witnessed the Union Carbide Gas Tragedy in 1984 and continues to struggle with the fallout of this disaster. The significance of the disaster however, extends beyond Bhopal. The factory site of the disaster, now an urban void in a dense neighbourhood of Bhopal lies abandoned and the stories that it contains, lie untold. Over the course of two weeks in January-February 2011 students and experts from multiple disciplines and backgrounds will converge in Bhopal and work together with local citizens in an attempt to understand the tragedy and its site in its conflicting interpretations. Through exploring the possible transformation of the site into a place of remembrance and a resource for empowering the local community the participants will also address the broader issue of how heritage sites with a troubled and troubling legacy can contribute to a better understanding of our times.

BHOPAL2011 looks at the possible protection, decontamination and rehabilitation of Union Carbide Factory as potential to revitalize the precinct and the community around the site and explores the possible approaches and mechanisms to do so. In exploring key issues linked to the emergence of the Bhopal Gas Tragedy Site as a cultural heritage site, BHOPAL2011 sets the ground for an collaborative and creative dialogue between disciplines of cultural heritage, architecture, urban design and applied arts.

Within a collaborative framework the conference and the workshop will explore three main themes:

  1. Challenges in Recognizing Contemporary Sites with a Conflicting Past as Heritage
  2. Challenges in Interpreting and Rehabilitating Sites with Contemporary and Conflicting Heritage
  3. Challenges in Harnessing Sites with Contemporary and Conflicting Heritage for Society Building

Last date for registration is December 1, 2010.

Papers are invited for the following (but not limited to) themes and proposals for organizing sessions are welcome.

  1. Commemoration & the Politics of Construction of Public Memory
  2. Public Participation in Revitalization of Sites of Memory
  3. Challenges in Rehabilitating Landscapes of Disaster
  4. Protection, Preservation and Interpretation of Sites of Conscience
  5. Heritage, environment and economy – Conflicts and Resolutions
  6. Gaps in the World Heritage list. Industrial & Modern Heritage of Asia, Africa and Latin America

The last date of submission of abstracts is November 15, 2010.

Cities, Design, Ecosystem services, General, Networks, Visualization

Resilience meets architecture and urban planning

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by Matteo Giusti [contact: matteo.giusti [at] gmail.com]
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Does resilience thinking and architecture really mix? The answer is a clear “yes” if you ask urban planner Marco Miglioranzi, and Matteo Giusti, Master student at the Stockholm Resilience Centre. Together with the German based firm of architects N2M, they have developed two projects led by resilience concepts. Their first work, based on social-ecological systems, was preselected in the EuroPan10 competition. The second one, “A Resilient Social-Ecological Urbanity: A Case Study of Henna, Finland” with an emphasis on urban resilience, has been published by the German Academy for Urban and Regional Spatial Planning (DASL) and also featured by HOK –  a renowned global architectural firm.
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The project proposes a wide range of theoretical solutions based on urban resilience which find practical application in Henna’s (Finland) urban area. Governance networks, social dynamics, metabolic flows and built environment are separately analyzed to ultimately restore, and maintain over time, the equilibrium between human demands and ecological lifecycles.
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But the project also challenges current urban planning practices as it states the city’s  future requirements to be unknown. As a result, it identifies “the development-process as a dynamic flow instead of a static state”. Time scale for urban planning is therefore included within an evolving spatial design.
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Diagram of the parametric cell structure: reversible space layer (upper left) and reversible building layer (right)The project description elaborates: “As a result, the planning is not static anymore. It is not a blueprint, not a collection of architectural elements to create an hypothetic Henna out of the current mindsets and needs, but a multitude of tools, methods, opportunities, options, to define a sustainable developing strategy to meet future’s demands. We keep an eye on time, its complexity and we humbly admit we cannot foresee future; we can only provide guiding principles from current scientific understanding to define a social ecological urbanity capable of sustainably moving on with unique identity.”
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All these theoretical premises ends up in Henna’s planning. This includes an energetic smart grid based primarily on Enhanced Geothermal Systems (EGS); community-managed greenhouse areas to enhance food local self- reliance; low-diluted sewage system to reduce water consumption; efficient reuse of municipal solid waste to reach the Zero waste goal; and a problem solving centre to analyze ever-changing social ecological demands. Time is included in space, people in their natural environment, urban services in ecological processes. An harmonious cycle of growth and decays.
Cities, General, Visualization

Wilderness Downtown

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Google Creative Lab has collaborated with the Montreal band, Arcade Fire to create a interactive web movie “The Wilderness Downtown” using Google earth.  Director Chris Milk combines the nostalgia of the new Arcade Fire song “We Used to Wait” with Google maps and street view images of the streets where the viewer lived to produce a very impressive combination of art and technology.

Wired blog Epicentre has an article that gives some background on the project:

The project came about one day when [director] Chris Milk and I were talking about Chrome Experiments and what can be achieved through a modern web browser and with the power of HTML5 technology,” said Google Creative Lab tech lead and co-creator of the project Aaron Koblin. “We were excited about breaking out of the traditional 4:3 or 16:9 video box, and thinking about how we could take over the whole browser experience. Further, we wanted to make something that used the power of being connected. In contrast to a traditional experience of downloading a pre-packaged video or playing a DVD, we wanted to make something that was incorporating data feeds on the fly, and tailoring the experience to a specific individual.

“One of the biggest struggles for a director is to successfully create a sense of empathy with their characters and settings. Using Google Maps and Street View we’re able to tailor the experience to each person. This effect is a totally different kind of emotional engagement that is both narrative and personally driven.”

…“Experiences” such as this will evolve to look much slicker in the future, but already, they’re capable of some fairly incredible maneuvers, integrating Arcade Fire’s stirring music with data from Google Maps and Google Street View, topping it all off with input from the user.

We’re impressed, but some streamlining will be required if bands that aren’t big enough to play Madison Square Garden, as Arcade Fire is, are going to be able to offer it. We counted a full 111 names in the credits.

Read More

Cities

Australian Radio on Resilience

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Australia’s ABC Radio show Future Tense recently had a show on Resilience Science that interviewed our colleagues Brian Walker, Guy Barnett, and Paul Ryan.

The show can be downloaded (download audio) or its transcript read online.  From the transcript:

Antony Funnell: But in a very practical sense, how does it make the situation better for the catchment authorities? Why is it preferable that they use resilience theory in their thinking, than the sort of traditional approaches that they’ve taken to solving these sorts of problems?

Paul Ryan: That’s a good question. Why should we try to bring in a new concept? Well in the past, we’ve used different approaches like sustainability as our sort of broad approach. Now sustainability as a concept is as a useful sort of catch-all, but when you really get down to it, what is sustainability? We’re not really sure what will be sustainable in the long-term. So trying to set a course or a pathway towards some sustainable point in the future, is a real challenge. What resilience thinking does is, it just brings a different perspective that says, What are the limits, for a start? Let’s understand the limits to this system so we know that all systems of people and nature that are interacting, people and their environment that are interacting. It has limits, and resilience thinking helps to identify those limits, and it says, ‘When you reach those limits, if you go beyond that, if you go over some tipping point, a threshold, if you go past that point, things will change, and they could change quite rapidly and quite unexpectedly, in ways that we don’t predict.

So resilience thinking for a start says ‘Let’s identify those limits to the system and how it operates’, and it helps us to think about how do we stay and manage within those limits? And so it’s sort of for a start, it sets the boundaries for a safe operating place, if you like.

The next question we ask is, Well what do we want to be resilient to? What are the possible things that could come along and impact on the system? And some of them are things we know a lot about – drought, bushfires, those types of things. But there’s a lot of challenges that we don’t know about, or there’s combinations of challenges. So if you think about the sorts of things that have happened in the last few years, just in Victoria alone, where I’m from. We’ve had the devastating bushfires, the drought, the global financial crisis which obviously affected the whole of Australia, we’ve had the threat of swine flu, we’ve had this combination of things that came along all at once, and we’re just not, traditionally we’re not prepared for those types of combinations of things. Resilience thinking helps us to think about those things in a structured way.

So the Catchment authorities have been dealing with lots of complexity, in all of these different issues, and our traditional approaches have been fairly one-dimensional. They assume that things will change in a fairly predictable way. Resilience thinking says things aren’t predictable, and we need to just accept that change is a really dominant part of our world, and so how do we work with that change and stay within some safe operating limits?

via Victor Galaz

Big Back Loop, Cities, Networks

Critical Reflections on resilience thinking in the Transition Movement

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The Resilience Alliance website has pointed to an interesting working paper from Alex Haxeltine, and Gill Seyfang from the Tyndall Centre in the UK Transitions for the People: Theory and Practice of ‘Transition’ and ‘Resilience’ in the UK’s Transition Movement, whose focus on developing transition towns to respond to the challenges of climate change and peak oil we have covered before on this blog.

Haxeltine and Seyfang state they write as ‘critical friends’ of the transition movement and address the transition movements equation of localism with resilience (which I believe is incorrect, and likely counterproductive).  It is wonderful to see resilience researchers engaging with they dynamic transition movement.  They write:

The specific language used is of “rebuilding resilience” – drawing on historical descriptions of towns in the UK around 100 years ago, the handbook argues that resilience has been decreased in recent decades. The narrative describes how localised patterns of production and consumption (and the associated skill sets and community cohesion) were eroded in a relentless shift to ever larger scale industrialized systems of production and consumption, made possible by the use of fossil fuel energy sources. Hopkins argues that there is now a great urgency to the need to rebuild resilience because of imminent disturbances (or shocks) in the form of peak-oil, climate change, and the associated impacts on economic systems and trading patterns (Hopkins, 2008). He links this urgency directly to our current oil dependency: “it is about looking at the Achilles heel of globalization, one from which there is no protection other than resilience: its degree of oil dependency” (Hopkins, 2008).

The framing of the Transition model provided in the handbook does explicitly draw upon the academic literature on resilience in socio-ecological systems (citing a 2006 introductory text by Brian Walker and David Salt for example), but what ideas are being taken from this literature, and to what extent is the resulting framework consistent with the interpretation of resilience quoted in section 2 of this paper? The Transition Handbook (Hopkins, 2008) cites studies of what makes ecosystems resilient, identifying: diversity, modularity and tightness of feedbacks:

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These initial resilience indicators rely heavily on equating resilience with the re-localisation of systems of production and consumption. So the Transition Handbook could be said to provide a starting point for talking about resilience in a Transition Town, but it is still a long way from being clear about what is needed in practice. Furthermore the evidence from observation of the local Transition groups (during 2008-2009) is that they are in an equivalent situation of trying to frame multiple actions in terms of the building of resilience but relying heavily on equating resilience with a re-localisation of production-consumption patterns.

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Resilience theory highlights the fact that building resilience to a specified disturbance (such as Peak Oil) does not necessarily provide the same resilience to all possible disturbances. Some properties of a Transitioning community, such as strong community networks and diverse skill sets, may help provide resilience to most disturbances, while other properties may be very specific to one disturbance. If one were to take the position that the greatest shocks in the coming years may, in the end, turn out not to be the ones that we expected, then successfully building a specific resilience to an expected threat (such as Peak Oil) may not provide resilience against realized disturbances. So what may be required is to build resilience to specific threats in a way that also builds system properties that help in coping with diverse possible threats – implying, for example, a need for a capacity to innovate.

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The current framing of resilience equates resilience with localisation in a rather unquestioning way, as demonstrated by the resilience indicators given in the Transition Handbook. We would argue that increasing any one of these indicators could actually either increase or decrease resilience to a specific disturbance, depending the exact nature of the disturbance and on the exact systemic changes used to enhance the indicator. We also argue that the desirable goal is not to simply increase such indicators as much as possible, but to find the right balance between resilience and other goals, such as quality of life and well being.

Cities

Seed Magazine on Urban Resilience

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Maywa Montenegro interviews our colleagues Thomas Elmqvist, Brian Walker and Guy Barnett for a long article in Seed Magazine on Urban Resilience.

The article covers many projects including the ongoing Urban Atlas Project, which aims to develop new tools for understanding the social-ecological capacity to provide ecosystem services.

The article writes Urban Resilience:

Urban centers have always been hubs of innovation, creativity, and wealth, but they are also hubs of crime, disease, and environmental pollution. Cities can be models of resource efficiency—the average Manhattanite uses only 29 percent of the energy an average American uses in a year—but they also concentrate the need for huge amounts of power, water, food, and other resources. In the developing world, cities are changing faster than scientists can understand the diverse factors driving those changes, and to complicate matters further, many of those forces operate in contradictory directions and at differing scales.

In short, cities are the quintessential complex adaptive system. Which makes them, in many ways, the perfect place to explore resilience.

Brian Walker is former program director and chair of the Resilience Alliance, a loose international coalition of natural and social scientists who, in their own words, “collaborate to explore the dynamics of social-ecological systems.” In 2005, recognizing the growing impact of urbanization, the Alliance held a series of brainstorming sessions, laying the groundwork for the “Urban Network,” based out of the Stockholm Resilience Center, an interdisciplinary research group that formed at Stockholm University in 2008.

The Urban Network has research sites in 12 cities: Bangalore, New Dehli, Cape Town, Johannesburg, Chicago, New York City, Phoenix, Canberra, Helsinki, Istanbul, and Stockholm. These cities span the globe and differ vastly in terms of culture, history, and economic development. The ultimate goal, according to Thomas Elmqvist, lead researcher of the Network, is to do a comparative analysis of these cities. How are they similar or different with respect to handling development? How do they compare it comes to withstanding shocks and surprises?

“As humans, we should try to understand how to manage systems in order to avoid passing thresholds,” says Elmqvist. But this is especially difficult in urban contexts, which have already been so transformed by humans that they’ve breached most of the thresholds ecologists are familiar with. When great expanses of concrete and steel now exist where trees and streams once did, new tipping points must be defined for places that are, as Elmqvist puts it, “already tipped.”

Case studies are now underway in each of the Network’s 12 participating cities. But in deciding what kind of data to gather, researchers have had to ask themselves: What would a city look like through the lens of resilience?

Metabolism

A city’s lifeblood is a continuous flow of stuff—fuel, consumer products, people, and services that enter it either actively, through human effort, or passively through natural processes like solar radiation, atmospheric currents, and precipitation. Ecologists often talk about these resource flows in terms of inputs and outputs. They’ve developed several budgetary models of accounting for them, including the well-known “ecological footprint.”

The resilience approach, according to ecologist Guy Barnett of the Urban Network’s Canberra research team, focuses less on the resources that cities consume and more on the interdependencies along the chain of supply and demand. Dependence on a single type of fuel as an energy source, for instance, creates a highly vulnerable system—especially if fuel prices are volatile or if the supply is prone to disruption.