Models, Metrics, and Future Scenarios
The third panel was organized to address some of the challenges associated with measuring change within an urban area, as it relates to sustainability. Panelists discussed some ways that urban change can be modeled into the future, how human and environmental outcomes can be measured, and what information is most useful or needed in assessing outcomes.
The City as a Unit of Analysis
Jonathan Fink, Vice President for Research and Economic Affairs and Director of the Global Institute for Sustainability at Arizona State University, claimed that cities offer an excellent place to study sustainability issues. If you focus on individuals, he said, investigations might prove to be “too slow and broadly dispersed.” If you focus on nations, he contended, “political barriers may stand in the way.” Cities, in contrast, are at the “intermediate scale and therefore may prove to be just the right size both for studies and pilot projects devoted to sustainability. Urban environments, he added, offer an additional bonus for researchers and practitioners wanting to understand what works and what does not. Simply put, "they are places where things are being done."
The focus on cities—and how to make them more sustainable—raises another critical issue, according to Fink: How can we develop a strategy that allows for a more coordinated flow of information? Progress on this front would enable us to move from detailed examinations of critical problems in specific cities to a broad analysis of sustainable urban development, based on "lessons in city living" from across the nation. The challenge would be to extract broad evidence-based lessons from the particular experience of individual cities. This would require input from a wide range of experts in the natural and social sciences as well as from policy makers and representatives of nongovernmental organizations. The approach would not only be cross disciplinary in nature but would also foster partnerships, helping to blunt the sharp distinctions that have historically existed between scholars and practitioners.
Fink cited the efforts of the Central Arizona Phoenix Long-Term Ecological Resiliency Programe, an initiative funded by the National Science Foundation (NSF),
which has examined the impact that the rapid growth of Phoenix's metropolitan area has had on urban ecosystems. He observed that the initiative, which is comparable to the Baltimore ecological resiliency project, has built excellent models for projecting trends in water, air, transport and land use. Yet, he cautioned, it has been less successful in integrating the data and insights into a fully drawn portrait of the future of the city. Universities, he observed, are not the only institutions handcuffed by traditional silos of information. Government agencies often find themselves constrained by similar circumstances.
The Phoenix project is part of a larger effort by the NSF to fund long-term ecological research (LTER). But as Fink noted, only two of LTER’s 26 projects have taken place in urban environments: in Phoenix and Baltimore.
Clearly, the NSF's ecological research agenda does not place the same weight on built environments as it does on natural environments (although because of demographic trends, several LTER projects have seen exurbs and suburbs encroach on their study areas). Nevertheless, farmland, forests and parks have traditionally been considered a more integral part of the environment than cities.
This will have to change if urban sustainability is to become a major aspect of ecological research in federal agencies. As the USDA's Bartuska noted, there may be more to the concept of 'eco-cities' than the current perceptions of the 'steel, glass and cement' would suggest. She noted that of the 193 million acres of forest managed by the federal government, 80 million acres are located in urban areas. That's more than 40% of the total.
Fink also pointed to the recently launched Global Cities Indicators Facility project, located at the University of Toronto and funded by the World Bank. The project is designed to encourage cities worldwide to collect "the same kind of data in the same way" and to "place their data all in one place." The ultimate objective is to facilitate access to urban research on global urban issues in ways that make comparisons easier to discuss and analyze.
It is a worthy goal, Fink said, that could go a long way to helping establish base lines that will be crucial for assessing trends in urban sustainability. Indeed research-based evidence, many participants noted, represents our best hope for changing minds and changing policies.
Between 1973 and 1998, Atlanta’s 13 county metropolitan regions witnessed the destruction of an estimated 55 acres of forest each day, resulting in a cumulative loss of 280,000 acres of vegetation during a quarter century of unprecedented growth. As Dale Quattrochi, a Geographer and Senior Research Scientist, Earth Science Office at the National Aeronautic and Space Administration (NASA), described it: One of America's premier Southern cities experienced a period of suburban "slash and burn."
As was the case in Phoenix, explosive population growth and the associated construction frenzy in Atlanta fueled an urban heat island effect in which temperatures in the city and even some suburbs far exceeded temperatures in the open areas lying at the periphery.
"We all know that cities are hot; nothing new here," Quattrochi said. But we may not be fully aware of how hot they stay once the sun sets. Detailed weather surveys indicate that two to three hours after sunset summer time temperatures in the center of Atlanta often remain 3 to 10 degrees F higher than in the outlying districts. Simply put,
the heat that builds up during the day is released much more slowly at day's end in places where cement covers much of the landscape and open space is in short supply.
Such “urban hot spots” are uncomfortable, unpleasant and less livable places that most people might prefer to avoid. But what is less well known, according to Quattrochi, are the increased public health hazards posed by the urban heat island effect. As he explains, higher temperatures accelerate the formation of ground level ozone (smog) as precursors (volatile organize compounds and nitrous oxides) combine photochemically in the lower atmosphere.
Quattrochi suggested that relatively inexpensive measures could ease temperatures, most notably the replacement of heat-absorbing, blacktop tar roofs (where temperatures can reach 175 degrees F on hot summer days) with light-colored roofs that reflect sunlight. Planting more trees would also help. Quattrochi cited the work of TreesAltanta, which hopes to plant 1 to 2 million trees in the city over the next two decades, as an excellent example of urban sustainability at work.
Indeed TreesAtlanta is a project that reinforces the three principles behind the concept of urban sustainability: There's an economic dimension (it creates jobs), a social dimension (it upgrades the appearance of the city and increases its appeal), and an ecological dimension (it aids in efforts to enhance the environment and improve the habitat).
Both policy makers and the public speak of the need to better understand urban ecosystems. Yet, examples of urban models and scenarios that shed light on this issue remain relatively few in number. That is why participants at the workshop were particularly eager to hear Steward T.A. Pickett, a Plant Ecologist and Distinguished Scientists at the Cary Institute of Ecosystem Studies, speak about the ongoing efforts of the Baltimore Ecosystem Study of Long-Term Ecological Research (LTER) Program, funded by the National Science Foundation (NSF).
The project, Pickett noted, focuses on "the structure and process of Baltimore's urban ecosystems," and how the city’s inhabitants have chosen "to use these systems." The initiative is comprised of several inter-related goals, some that seem within reach in the near term and others that are likely to take some time to fulfill.
These goals, Pickett said, include doubling the city's tree canopy, creating ample, well-maintained public recreational space that can be easily accessed (especially by poor citizens), protecting Baltimore’s ecology and biodiversity, and establishing the city as a national leader in sustainable food systems.
The vision that drives these goals is based on a desire to create a better life for the people of Baltimore while conserving and protecting the city's ecology and biodiversity —that is, the goal is to turn Baltimore into a model for sustainable urban growth.
"We rely on watershed measurements to gauge our progress," explained Pickett. "That means we invest both a great deal of time and money assessing the water quality of our streams, the biochemistry of the soil and levels of atmospheric pollutants." The staff also integrates large amounts of economic and social data into their analyses—detailed information about the city's demography and economy, transportation systems and construction sites, health services and recreational facilities, and many other factors. Not a single trend is too big or too small. Indeed no mega-trend or minor detail goes unnoticed. Borrowing a term used by hydrologists, Pickett called this "synoptic
sampling"—an effort to present a broad picture of resource use and development trends in Baltimore based on a relentless pursuit of facts and figures.
But Pickett also maintained that this has not been a top-down approach led by public officials and government bureaucrats. Part of the process has included an ongoing dialogue with the citizens of Baltimore to determine what they hope the project will achieve in making the city a better place to live. He estimated that 1,000 of the city's residents have participated directly in this exchange and that many more have heard about it from friends and in the media.
Collecting and Analyzing Data
"Fear and greed" motivate my commercial clients, said Thomas Parris, Vice President and Director of Sustainability Programs at ISCIENCES LLC. "Should we expect anything more or less from those asked to respond to ecological challenges?" A broader understanding of thresholds is one of the keys to urban sustainability, Parris said. "Cities," he went on to note, "are highly engineered environments," and it is important to think of them in terms of what they require in order to function well—both now and in the future.
If the demands placed on a city's requirements exceed the supply of resources that are available to meet them, the city will be placed at risk. That is why, according to Parris, we need to study not only population and economic trends, but also energy and water use, the prospects for technological advances and the possible impact of climate change. Each of these factors, and many more, will impact the requirements placed on an urban environment by increasing the demand for ecological services. Technological advances, in turn, would enhance the efficiency of the delivery systems (thus extending the use of these services).
Adding to the complexity, Parris asserted, is the rising number of unusual events that are impacting cities—including unprecedented annual variations in rainfall, withering heat spells, intensive storms and flash floods.
Other speakers, including Peacock and Kuipers, had made the same observation, but Parris added a new twist to the discussion. Because we are dealing with rare events, he said, we have been unable to observe a sufficient number of them to draw insightful conclusions on how they might affect urban environments. Nor have we been able to project the long-term impact they are likely to have on urban sustainability. Hinting at the same challenges raised by Peacock, Parris plaintively inquired whether these rare events will become commonplace and, if so, what does that mean for our cities?
"We do financial, economic and even estate planning," Parris wryly observed, but we "don't do spatial planning," and for this reason it is extremely difficult to devise an effective strategy for sustainable urban growth.
Jennifer Wolch, Dean, College of Environmental Design and William W. Wurster Professor of City and Regional Planning at the University of California, Berkeley, expanded on Parris's observations by suggesting that we need to develop more integrated models for cities that are capable of providing “multi-sector, cross-over and real-time analysis of events.”
While not discounting the importance of data, Wolch echoed the concerns of some of her colleagues when she questioned whether more precise large-scale models would serve as the basis of better decision making. "No one wants to make decisions in
the dark," she asserted. But she wondered if the quest for more high-powered, large-scale models ran the risk of becoming "cul-de-sacs into which researchers happily go, running their regression analyses, while the rest of the world goes on without them." Most models, she also advised, “don’t capture some of the most critical aspects of sustainability” that “reach beyond any particular metropolis and connect to global production and consumption networks.”
To counteract these shortfalls, Wolch contended that large-scale models needed to be theory-driven, multiple-scaled and, most importantly, based on high-quality data and state-of-the-art technology. Such urban models exist, she said, but they are too few in number. She lauded the efforts in Phoenix and Baltimore but maintained that such initiatives needed to be replicated elsewhere not only for the sake of other cities but also to build a complete portrait of trends in urban sustainability across the country.
She also cited a smaller scale initiative in Southern California that was using a GIS planning tool to provide integrated analyses of trends in habitat and watershed conservation and parks and open space. The goal has been to determine whether the use of selected parcels of parkland could deliver multiple (and mutually reinforcing) benefits —both for local residents (particularly the poor) and fauna and flora species preservation. In other words, could the GIS planning tool help policy makers select new swatches of parkland that would maximize the payoff for people and the environment?
In addition, Wolch observed that none of this technology, data collection and analysis comes cheap, and that it is unrealistic to believe that it can be successfully put in place and maintained without government involvement at all levels.
Nongovernmental organizations, she acknowledged, are gaining increasing expertise in using sophisticated data and analyses when engaging both policy makers and the public in discussions on critical urban issues. But government remains the most important player, not only because of the resources it has at its disposal to assemble and utilize data, but also because the information and analysis that is derived from these data bases and models generally constitutes a public good.
Nevertheless, she regretted that governments have rarely displayed the stamina and commitment for long-term data-collection projects and, as a result, virtually none of these projects has been open-ended. "At some point," she observed, "they become 'legacy initiatives' of interest to planners and historians, but of limited value to policy makers simply because they tell a story of the past" instead of shedding light on the present and future.
Finally, Wolch noted that high-quality data and analysis could help us better understand the factors that drive high-performance communities.
"Each city is different," she said, "and big cities even have very different micro-environments within their borders." That makes measuring sustainability a difficult task because there are so many matrices involved." Yet, at the same time, she added that we all know of examples of success both at the neighborhood and city-wide levels. What we need to do, according to Wolch, is to examine "what accounts for these successful experiences" and what can be done to replicate them.
In other words, we need `'to understand what works, to be able to build models capable of assessing alternative scenarios, and to find ways to make cities more resilient" based on high-quality information. This will require integrated data on "energy, health, food habits, consumption, buying habits and ecosystem services." She concluded her
remarks by adding that we need this data not just for one or two cities "but for many cities" if we hope to devise a comprehensive strategy for sustainable urban growth that cities and suburbs across the country find of use.
Computer-generated tools, in fact, have vastly expanded the level of detail and refinement available for researchers studying the city and countryside. “These are the best of times for geographers,” declared Glasmeier. “We can analyze data at multiple scales over distinct time periods. We can integrate satellite data. We can integrate microbial data. We can put sensors inside people and have them walk around. We have enormous capacity to track people.”
“The critical question,” Glasmeier said, is this: “Do we really have the tools to analyze” all of this data? Participants raised similar questions. Will this vast treasure trove of data allow the public and policy makers (or even researchers) to see the problem more clearly and to make better decisions? Are we confusing ever larger amounts of data and information with in(fore)sight and innovation? Are there limits to what additional data and information can do in the absence of comprehensive blueprints for growth at the local, regional and national levels—a blueprint that is truly sustainable? In short, what do we need more of: additional information or a better plan? Or, as Glasmeier observed: “We are good at measurement. We are much less effective at long-term monitoring. As a result, “how do we know where we want to be?” In other words, do we run the risk of being lost in a mountain of data?