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Log cabin

In my mind, my hometown will always be a city of 24,000 people. It’ll also be supported by three major manufacturing companies. And it’ll always have a certain, intangible something. Of course, today West Bend has 5,000 more residents despite the demise of all three manufacturers. And every time I return, that certain something isn’t quite the same either. It’s like waking from a dream I can’t entirely reconstruct.

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Mos Eisley, the wretched hive of scum and villany

George Lucas hates cities. At least that’s what I gather from decades of watching and rewatching the original Star Wars movies.

The Star Wars movies are famous for hewing to archetypal stories—hero sets out to save galaxy from evil warlords, hero confronts his (familial) past, hero grapples with his role as a savior. And the movies’ portrayal of urban agglomerations is similarly archetypal, drawing on a long tradition of damning the city while praising the countryside.

Let’s start from the beginning…

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Gold L.A.

The U.S. Census released a report on urban population on Monday, and in it was a perhaps-unexpected fact: Of the ten most densely populated cities, seven of them are in California. Indeed, California’s showing was so strong that the great bastion of urbanism in the United States — the New York-Newark metro area — just barely made the top five.

John King, the San Francisco Chronicle’s urban design critic, interviewed a number of experts about California’s unique status. Among them was Jon Christensen, executive director of the Bill Lane Center for the American West at Stanford University. One of Christensen’s quotes caught my attention, so I followed up with him via email to explore why California is such a hotbed of urbanism. Our correspondence follows:

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Mos Eisley, the wretched hive of scum and villany

George Lucas hates cities. At least that’s what I gather from decades of watching and rewatching the original Star Wars movies.

The Star Wars movies are famous for hewing to archetypal stories—hero sets out to save galaxy from evil warlords, hero confronts his (familial) past, hero grapples with his role as a savior. And the movies’ portrayal of urban agglomerations is similarly archetypal, drawing on a long tradition of damning the city while praising the countryside.

Read more at the new Per Square Mile.

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Milan, 1913

Note to WordPress.com followers: Per Square Mile has moved to a private host. Your old WordPress.com follows and email subscriptions won’t work as WordPress will not share that information. Head over to the new Per Square Mile for the latest.

Once a road, always a road. That’s the gist of a recent paper that studied 14 different municipalities in the Groane region of Italy near Milan. In cataloging 174 years of road construction, the study’s authors discovered that nearly 90 percent of the regions 100 most vital routes today were already present in 1833.

The researchers also uncovered evidence that the layout and characteristics of road networks are indicative of the age in which they were built. This is nothing new. Take a look at any metro region surrounded by a postwar subdivision—stick straight roads of the late 19th and early 20th centuries give way to ever more writhing tangles of spaghetti. What’s new is that this study claims that top-down planning didn’t drive the changes. Rather, the researchers say Groane’s roads reflect broader societal changes, that the unique circumstances of each era—agricultural through modern—shape road networks more than central planning—or lack thereof.

To arrive at that conclusion, physicist Marc Barthélemy and his colleagues digitized roads using maps and aerial photographs from seven different dates between 1833 to 2007. They threw the resultant vectors into a geographic information system, or GIS, and then distilled primal graphs—simplified maps that show only roads (called “links” in graph theory) and intersections (“nodes”).

Between 1833 and 2007, the number of intersections grew proportionately with population. The number of intersections skyrocketed—there were only 255 in 1833 but over 5,000 in 2007—but the number of connections remained relatively constant at 2.7 on average. The number of roads also increased linearly with the number of intersections. It’s almost as if the expansion of Groane’s social network was mirrored in its transportation corridors.

How those roads interacted with each other changed through time. In the early days, many roads either intersected another mid-link—forming a T-junction—while the others simply petered out in a dead end. Main drags radiated out from town centers like spokes on a wheel. Congruent 4-cornered intersections were rare. Yet as time progressed and cities spread into the countryside, the previous radial expansion gave way to the grid. In other studies, the advent of the grid was attributed to the arrival of master planning, but here in Groane, Barthélemy and his colleagues note that urban planning was never the region’s strong suit. Groane, they write, “never witnessed any large scale planning whatsoever.”

It is because of Groane’s lack of central planning that Barthélemy and his colleagues are able to draw their conclusion, that road networks morphed not because of changes in our approach to planning but because of changes in society as a whole. In essence, they assert that changes to the network were not consciously done.

It’s not surprising, really. Roads are built to handle the traffic of their time. When navigating Cambridge’s labyrinthine streets, I’m constantly reminded that they were built for horse and carriage, not a horseless carriage. The demands of the automobile are sufficiently different from horse or foot traffic. Their greater speeds require straighter rights-of-way. Intersections need to be clear and predictable. Navigation also needs to be simplified—drivers moving at 10 miles per hour have more time to look for their next turn than those moving three times faster. The grid tackles these problems with aplomb.

Road networks are a product of the processes that created them, whether that be wagon traffic from farm fields plodding to town or taxi cabs streaming out from downtown. Discerning process from pattern is also the domain of another field—landscape ecology. Landscape ecologists sweat the details of spatial configuration to learn what ecological processes are at work. The laws of landscape ecology apply just as well in the city as they do in the natural world. The city is nothing but an anthropogenic ecosystem.

Ever since Geoffrey West and his colleagues uncovered the mathematics behind why big cities are economically successfully—but also crime ridden—it has been popular to search for formulae that describe urban processes and city development. This paper by Barthélemy and his colleagues is but the latest addition to a growing literature. By themselves, these discoveries are clever and insightful. But the interesting stuff will happen when urban planning completes the transition from an observation-based science to a mathematical one, much as ecology did in the recent past. Then we’ll have a real sense of how these models will change our understanding of cities.

Map scanned by University of Texas PCL Map Collection.

Source:

Strano, E., Nicosia, V., Latora, V., Porta, S., & Barthélemy, M. (2012). Elementary processes governing the evolution of road networks Scientific Reports, 2 DOI: 10.1038/srep00296

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The City 2.0

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TED is currently in full swing, and the program this year has an entire section devoted to the city. Fitting, given that this year’s TED Prize went to a city-centric project, one that hopes to crowdsource ideas to solve urban problems and reinvent cities. It’s predictably named The City 2.0. The site has a flashy splash page, but the innards still need some work—tapping in my current city of Cambridge, Massachusetts, sent me to a generic index page that encouraged me to “get connected” with other aspiring urban planners in my area, but responded to my clicks with little more than a broken Google Maps interface and some “COMING SOON” dialog boxes. For now, it’s long on pizzazz and short on details.

The TED Prize website fortunately has more on what The City 2.0 hopes to accomplish:

For phase I, the website (www.thecity2.org) will focus on helping individuals in forming cross-disciplinary groups to:

  1. determine the issue they want to tackle (i.e. traffic, lack of trees);
  2. determine a solution;
  3. develop an action plan;
  4. work to implement the solution;
  5. share the story of their success or failure with others.

Companies and organizations will be able to offer their tools to site users for use in executing their action plans. Ten micro grants of $10,000, coming out of the $100,000 TED Prize money, will be awarded in July 2012 to ten local projects that have the best hope of spurring the creation of their City 2.0.

To be clear, that’s $100,000 to be equally split among ten groups. Not a lot of money to tackle problems that probably need millions, even billions, of dollars thrown at them. Thankfully, there’s more:

As the site continues to grow and the overall platform grows we expect to:

  1. expand the functionality for individuals to connect and act;
  2. develop and design templates for knowledge sharing between new ideas formulated on the site and preexisting projects;
  3. build out our resource section with new local and global partners;
  4. introduce technology solutions for non-web based communities;
  5. expand our financial incentive program with larger grant offerings for active projects
  6. establish local and/or global gatherings on the City 2.0.

That’s a little better. This part of the project should have a longer-lasting impact than the small pot of grant money. Local civic groups often don’t have the skills or wherewithal to build a connected platform to publish their ideas and solicit feedback. The City 2.0 could provide that. But soliciting ideas is just the beginning. Many other hurdles stand in the way, and from what I can see The City 2.0 doesn’t propose how to address them.

The most obvious barrier is money. The City 2.0 acknowledges that to be successful it needs “companies and organizations willing to offer empowering resources” and “financial support”. It seems to me they are simply hoping companies and philanthropists will step forward and reward the best projects. That’s papering over a big problem.

The next issue is how to choose the best project. The City 2.0 says in its intro video that it will “combine the reach of the crowd with the power of the cloud”. Both crowdsourcing and the cloud are hot topics these days. Crowdsourcing in particular can give people a voice who otherwise may not have spoken up, and it leverages the law of big numbers to extract a handful of singular, stand-out ideas. But the real problem with crowdsourcing solutions for cities is more fundamental than that: Who decides which ideas to implement?

Lior Zoref, a crowdsourcing advocate, gave a TED talk this year about the wisdom of crowds in which he was joined on stage by an ox. After the gasps died down, he asked everyone to guess the weight of the animal and submit it to a website. At the end of his talk, he announced the average of the audience’s guesses: 1,792 pounds. The real weight of the cow? 1,795 pounds.

It is an impressive demonstration, but one that doesn’t sell me on the crowd’s ability to reinvent the city. That’s because crowd wisdom cannot apply to projects like The City 2.0. With the ox’s weight, there is one right answer. The crowd’s wisdom can be unambiguously verified. But with ideas and concepts like those solicited by The City 2.0, there is no right answer. And you certainly can’t distill an “average” idea from them all. Ultimately, a panel will have to pick the winners and losers. Those panelists will have enormous sway over the outcome of The City 2.0. If they are experts in their field, what’s to say the winners will be revolutionary, or even substantially different from their own work?

If winners are picked by popular vote—which I highly doubt—that, too, is no guarantee that the most promising proposals will be selected. People don’t always know what they want. “It’s really hard to design products by focus groups,” Steve Jobs once said. “A lot of times, people don’t know what they want until you show it to them.” There may be wisdom in crowds, but genius is usually confined to individuals.

I suspect it’ll take true genius to remake the city. We’ve been spinning our wheels in recent years, rehashing concepts of the city that have been around for decades, even centuries. Those ideas may have worked well in the past, but they didn’t have to contend with airports, globalization, or climate change. Today’s best solution may be unlike anything we have come to expect from cities.

I’m sure The City 2.0 will fund some great projects, but we won’t really know how they work until we really try them. Not small bits here and there, but big implementations. Trying on that scale takes money, and the only organizations with the money to do it are governments.

Does that mean it’s back to the old way, sitting through planning meetings and zoning boards? Maybe. Crowdsourcing is a great way to gather ideas, but implementing them takes community and persistence and enthusiasm. It’s possible that a website could create that community, but I’m skeptical—most social media tools piggyback on existing, real-world social bonds. I know I sound pessimistic about The City 2.0. I’m not entirely. I hope that the project will uncover a work of genius that would have otherwise been ignored, but I’m not holding my breath.

Photo from The City 2.0.

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Red-eyed Vireo

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Earlier this week I pointed out that urban areas can actually increase tree cover over time, albeit with a caveat. The two studies I cited measured tree cover and only tree cover—they made no claims about ecological function. Luckily, other studies have done just that, including one that looked at migratory bird use of greenways in urban areas.

Migratory routes are important, though most research into migratory bird decline has focused on habitat loss in their breeding and wintering grounds. That has left a large piece of the puzzle unsolved—the habitat between point A and point B. Think of it this way: If snowbirds—you know, northern (human) retirees who flock to warmer climes in the winter—started disappearing and our best solution was to look for them at their apartment in New York or their rental in Boca Raton—ignoring rest stops and motels along I-95—we’d be doing a great disservice to our older generations. Ignoring flyways is similarly foolish.

There have been studies in more recent years that aim to fill this gap, and one published in 2009 by Salina Kohut, George Hess, and Christopher Moorman picks up the trail along, well, trails. They surveyed bird species abundance and richness—how many and how varied the itinerants were—in 47 greenways in and around Raleigh, North Carolina.

Greenways are a common and convenient way for cities to conserve natural habitat. Their linear form is well suited to urban areas, and they easily double as parks or recreational trails. They also can serve as stop-over habitat for migratory birds. Kohut, Hess, and Moorman were hoping to find the right type of corridor for migrating birds, where our feathered friends can take a load off and fatten up.

It turns out that most birds were not picky and would stop at just about any greenway, regardless of vegetation, adjacent land use, or corridor width. That’s not to say all greenways were entirely equal. Overall, birds favored corridors with taller trees and lots of native shrubs teeming with fruit. And among birds that live in forest interiors far away from human development and even open fields, greenways wider than 150 meters (about 500 feet) surrounded by low-intensity development were the most popular.

None of the greenways Kohut and her colleagues studied were as good as a regular forest, though. Still, with some tweaks—including widening corridors, siting them near low-intensity development, and planting with natives—greenways can make decent stand-ins for the real thing, at least as far as migratory birds are concerned. Residential neighborhoods can even make themselves into agreeable stopover habitat by mimicking vegetation found at popular stops along the flyway.

So greenways make for good bird habitat, but let’s not forget that they’re good neighbors, too. In addition to helping migrating fauna, they boost property values, add recreational opportunities, and work well as commuting corridors for cyclists. Five benefits from one land use. Not too shabby.

Photo by qmnonic.

Source:

Kohut, S., Hess, G., & Moorman, C. (2009). Avian use of suburban greenways as stopover habitat Urban Ecosystems, 12 (4), 487-502 DOI: 10.1007/s11252-009-0099-6

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