At the heart of Shenzhen, China, the city’s massive, wavelike Civic Center stands surrounded by a mind-boggling panoply of futuristic skyscrapers. Forty years ago, this area was home to just a few scattered fishing villages on the Pearl River Delta. Today, approximately 24 million people live within Shenzhen’s greater urban area.

In China, Shenzhen has come to stand for something much bigger than itself. On a hill downtown, a statue of revered former Chinese leader Deng Xiaoping striding purposefully toward the Civic Center helps explain why. Deng took control of China in 1978, after the death of Mao Zedong. The transition marked an end to decades of isolation from the outside world that had been dominated by command-and-control planning. Deng turned the country in a radically new direction, launching the Reform and Opening program to loosen the strictures that had bound the country for so long. And Shenzhen led the way into the future.

Deng granted the newly created city a license to operate as an economic superlaboratory, a place to explore the promise of the free-market economy. It was a sink-or-swim proposition, and in the years since, Shenzhen has succeeded wildly. Yet Shenzhen’s spectacular growth has come at a cost. As the area transcended its naturally marshy environment and turned from literal backwater into economic powerhouse, much of its land cover succumbed to blacktop and concrete. During storms, the abundance of paved-over land caused widespread flooding, as well as large-scale releases of urban pollution into nearby Shenzhen Bay and the Pearl River Delta.

Shenzhen is hardly alone in facing these problems. But continuing in its role as a national hotspot of innovation, it has become a unique laboratory for thinking about how to build livable cities throughout China and beyond.

Six miles northeast of Deng’s statue, Professor Huapeng Qin stands on a rooftop, surrounded by sensors measuring wind speed, temperature, and evaporation. He is looking for solutions.

Based at the local satellite campus of Peking University, Qin is at the forefront of an effort to turn Shenzhen into a “sponge city.” Using techniques that mimic nature, sponge cities can catch, clean, and store rain, which reduces the risk of flooding and keeps local drainage and water treatment systems from being overwhelmed.

Although it takes its cue from centuries-old thinking, the modern concept of the sponge city began forming in Europe, Australia, and the United States in the early to mid-1990s. The movement was a reaction to two common phenomena in urban development. First, just as happened in Shenzhen, most rapidly developing cities pave over huge amounts of land, eliminating a significant amount of natural forest cover, filling in lakes and wetlands, and severely disrupting the natural water cycle. Second, the traditional approach to urban stormwater management has focused on moving as much rain as possible off the land as quickly as possible, not capturing it for reuse.

Sponge city thinking marks a significant shift away from traditional “gray infrastructure”—think concrete pipes and dams—to “green,” or natural, infrastructure such as rain gardens and forests. The sponge city approach aims to restore some of those natural functions by allowing urban areas to transform the menace of stormwater into a boon: extra water for dry times.

Sponge city techniques therefore have multiple benefits. They can help soften the impact of flooding, improve both water quality and water supply, and help fix environmental problems. The sponge city concept is a relatively new arrival in China, but it has gained traction here fast. That’s partly due to the country’s tremendous growth over the past several decades, which has drastically altered the landscape. It’s also due to a new mindset about the risks of pursuing prosperity at all costs. In July 2012, a huge rainstorm in Beijing led to flooding that caused 79 deaths and an estimated $1.7 billion in damage. The incident galvanized national leaders.

In late 2013, President Xi Jinping officially endorsed the sponge city concept, and the following year the Ministry of Housing and Urban-Rural Development issued a set of technical guidelines aimed at ensuring that 70 percent of surface runoff be captured in place. The central government also launched what would ultimately become a 30-city pilot program to prove out the concept. Shenzhen is one of the pilot cities, and it’s no coincidence that the sponge city concept has gotten more traction here than anywhere else in China. From financial policy to the tech sector, “Shenzhen has always been very willing to borrow ideas from outside China and try them out,” says Qin. The sponge city idea is no different. “First it was just scattered pilot projects, but now the concept is being incorporated into Shenzhen’s master plan.”

In this case, Qin and his students are trying to learn more about techniques for creating green roofs, using plants grown in a medium of lightweight engineered soil to catch rain where it falls, slowly meting it out afterward. Such techniques are “very similar to natural systems,” Qin says. “Natural systems look very simple, but the processes are very complex. So we’re trying to understand those processes.”

A sponge city has several interchangeable building blocks. At a large scale, protecting or restoring forests and natural ground cover helps give water a chance to sink in. At smaller scales, there are several options. Permeable pavement can be used on roadways, sidewalks, and pathways to allow water to infiltrate the ground, rather than wash off into the local stormwater system. Retention ponds and constructed wetlands help catch and filter water, allowing it to slowly percolate into the local water table. So-called rain gardens perform a similar function at a smaller scale, and can easily be incorporated into neighborhood green space or even homes. Green roofs catch and filter rain, along the way watering plants that, Qin says, can help reduce surface temperature by up to nine degrees Celsius.

Shenzhen’s embrace of the sponge city concept has been driven by its spirit of innovation, but also by the fact that the effects of an unbalanced water cycle are often plain to see here. Heavy rains can overwhelm local water treatment plants, sending nutrient-laden wastewater directly into Shenzhen Bay and the Pearl River Delta, causing large algae blooms. People are also worried about the impacts of climate change. In what may have been a taste of what’s to come, Super Typhoon Mangkhut, which hit in 2018, blew down half the trees in the city.

Qin says computer models predict that with climate change, total annual rainfall will be comparable with current levels, but that precipitation will be much “flashier”: extreme events like short-duration, high-intensity rainstorms will become more common. This area has absorbed an influx of millions of people over the past few decades, largely by turning its back on the water that was once its defining characteristic. Now, Qin and others across the city are committed to finding new ways forward. The lessons they are learning and applying here are the first steps in what may soon be a sweeping transformation—not only in the city around them, but also throughout China.

“Sponge cities are just one example of how China is taking up the sustainability agenda,” says Zhi Liu, director of the Peking University-Lincoln Institute Center for Urban Development and Land Policy. Acknowledging the urgency of building climate resilience in the face of extreme weather and other challenges, he says, “This is not something China wants to do in order to look good. It comes out of necessity.”

Until two years ago, the 105-acre patch of green space now known as Honey Lake Park was an abandoned agricultural experiment station. The dominant features of the park, which sits not far from downtown Shenzhen, were a neglected grove of lychee trees and two fish ponds. Today, walking into the park feels like walking into an architectural rendering. Yet in the company of an expert, it quickly becomes clear that the park is not only aesthetically pleasing but also eminently functional.

Yaqi Shi, a technical director with the Shenzhen-based Techand Ecology & Environment company, helped design the park. The paths that we are walking on, she explains, are constructed of permeable pavement, and the park’s rolling contours are hugged by small swales that help slow and catch runoff. A series of ponds in the middle of the park is sown with native rushes that Techand raised in its own nursery. Signs throughout the park point out the various sponge city elements and explain how they work.

Shi, whose professional focus is ecological restoration, speaks with the brisk economy of an engineer. But the delight in her voice is evident when she speaks of the evolution of this project. “The park turned out to have a really user-friendly feeling,” she says. As we walk, Shi points out a library, a children’s play center, and the local wedding registration office, all within the boundaries of the park. A pavilion at the edge of a pond provides an ideal backdrop for cooing newlyweds to pose for portraits.

A walk with Shi also makes it clear that much of the technology underlying sponge cities is, in fact, surprisingly low-tech. The real art of the approach lies not so much in being technically clever, but simply in being thoughtful. Shi explains, for example, that much of Shenzhen is underlain by a layer of clay, which prevents water from infiltrating very far into the ground. To make permeable pavements work means hiring contractors to dig out the clay, sometimes to a depth of six feet, and replace it with gravel and more permeable soil.

Nonetheless, once you get a sense of what to look for, Shenzhen suddenly starts to seem like an entirely different city. On the northwest side, a relatively new suburb called Guangming has wholeheartedly embraced the sponge city concept. The suburb’s recently built New City Park is a model of retaining stormwater in place, from a water-absorbing latticework in the parking lot to permeable pavement on the paths, to swales and miniature, artificial wetlands designed to slow and soak up water. The massive adjacent public sports center has a green roof and a vast expanse of permeable bricks and pavement. The anaerobic digesters at the Guangming water treatment plant are covered by an enormous green roof; there’s another at the foreign languages school. Over at the high-speed rail station, where bullet trains thunder in from Hong Kong, the streets out front are made of permeable pavement.

After a while here, it’s hard to resist the temptation to, little by little, empty your water bottle onto Shenzhen’s sidewalks and streets, simply for the novel sensation of watching the water disappear into what otherwise appears to be regular blacktop and concrete.

Back downtown, the Nature Conservancy’s Xin Yu shows me another side of the sponge city revolution. We meet in the lobby of a Hilton hotel just a mile from the Civic Center and the nearby hilltop statue of Deng Xiaoping. After quick pleasantries, Yu takes me out a back service door. Compared to the airy elegance of the hotel lobby, it feels as if we’ve passed through a portal into another dimension.

We find ourselves in the narrow alleyways of an area known as Gangxia, a former farming village that Shenzhen gradually engulfed, and that subsequently metamorphosed into a crowded warren of five- and six-story apartment buildings. Gangxia and other so-called urban villages are a phenomenon found in practically every Chinese city, and are testament to the frenetic pace at which the country has urbanized over the past 40 years. They are often gritty, but they’re an important haven for low-income migrants who otherwise wouldn’t be able to afford the high rents of most urban areas. They typically come to form largely self-contained communities with small businesses that cater to all the needs of their residents, from vegetable sellers to modest karaoke parlors.

Yu nimbly leads me through the narrow back alleys, and it quickly becomes clear that “village” is a misnomer. The densely packed buildings here are known as “handshake apartments,” built so close together that residents of neighboring buildings can reach through their windows to shake each other’s hands. Restaurants are preparing for the lunchtime rush, and the air is filled with the staccato rhythm of vegetables being chopped. Business here, Yu says, is vibrant and extremely competitive: “These alleyways really are alive.”

Gangxia’s original residents didn’t technically own the land upon which their houses were built, but they did have rights to use that land. As Shenzhen grew during the 1980s and 1990s, they replaced their own houses with apartment buildings, often keeping one floor for themselves and renting out the rest, to take advantage of rising rents.

The Nature Conservancy (TNC) has played an important role in showing that it’s possible to incorporate sponge thinking even in the heart of the urban jungle. “There are a lot of ideas, but the government or companies can’t necessarily try things out,” Yu says. “NGOs can. We can figure out what ideas work and take them back to the government to promote more broadly.” (Due to the current political climate in China, Shenzhen municipal officials were not in a position to meet for this story.)

Yu opens a gate to an otherwise nondescript apartment building and climbs several flights of stairs to the roof—and an improbable flourish of lush greenery. A multilevel lattice framework groans with plants of every description. This green roof, Yu says, catches over 65 percent of the rain that lands on it.

Showing what’s possible hasn’t always been easy. When TNC first started this green roof project, Yu and his colleagues had to contend with angry neighbors who thought they were illegally adding another story to the building. “People kept calling different government departments: the police, or the construction bureau, or the city administration bureau,” Yu says. That led to several visits from local code enforcement teams, who used ladders to gain access to the building and a cutting torch to try to dismantle the garden’s supporting framework. “They kept asking for approval documents,” Yu says, and laughs. “But those don’t really exist. We had nowhere to go to get them.”

With time, however, efforts like this have spread broader awareness of the sponge city concept. “Public consultation—how you get the public to understand what this is about—is very important,” says Liu of the Lincoln Institute. “I think NGOs can play a big role in this area, and TNC is a trusted international NGO in China.”

TNC’s work has also gained the backing of officials and business leaders. Yu was invited to be a member of the technical committee for Shenzhen’s municipal sponge city program. When corporate tech giant Tencent decided to incorporate sponge city techniques in its iconic new headquarters in Shenzhen, the company turned to TNC for ideas. And Tencent’s founder, chairman, and CEO, Pony Ma, is not only a member of TNC’s board of directors for China, but also a delegate to the powerful National People’s Congress. There, he has made sponge cities part of a broader personal platform of advocating for nature-based solutions. Ma has also inspired fellow business leaders to commit to—and invest in—ensuring that their businesses meet sponge city standards in Shenzhen.

Some 1,200 miles north of Shenzhen, in Beijing, Kongjian Yu’s office seems to sprout a plant from every spot where he hasn’t managed to stuff a book. The Where the Wild Things Are feel is entirely consistent with Yu’s personality, which is driven by a kind of restless energy. It’s hard to imagine him sitting in one spot for five minutes.

Yu, who was born in a small farming village in coastal Zhejiang Province, went abroad and earned a Doctor of Design degree at Harvard, in 1995. Upon returning to China, he was deeply disheartened by the direction that development had taken. “When I came back, I was shocked by the scale of urbanization,” he says. “I was amazed by how this process ignored all our natural and cultural heritage, filling in wetlands, destroying the rivers, cutting down the trees, and wiping out all these old buildings.”

Yu was hired as an urban planning and landscape architecture professor at Peking University. In the staid world of Chinese development theory, he has made his name as something of a flower child—and a gadfly. Yu became a prodigious author and tireless lecturer, and turned out a series of open letters to China’s top leaders. He called for China to abandon its mania for building monumental public squares; advocated for a revival of the traditional Chinese approaches to farming, water management, and settlement; and suggested that the money allocated for annual National Day parades be better spent building good parks.

Above all else, Yu railed against China’s obsession with concrete, a repudiation of decades of thinking here. “The philosophy in China, in Mao’s era, was that humans can beat nature,” Yu says. “And that caused a lot of disasters for us.”

That attitude only accelerated in the years after Mao’s death, and by the early 21st century, China was setting records for the amount of concrete it was pouring each year. Global systems demystification guru Vaclav Smil has estimated that China used more cement in just three years, 2011 to 2013, than the United States did in the entire 20th century.

While Yu has encountered opposition to his outspokenness, he has also tapped into a growing demand for this new kind of systems thinking. Today, in addition to serving as dean of Peking University’s College of Architecture and Landscape, he heads a 600-person landscape architecture and urbanism consultancy called Turenscape. Municipal governments across China routinely seek the company out for help. He wrote the definitive two-volume practitioners’ guidebook on sponge cities in China, and contributed to the Lincoln Institute of Land Policy book Nature and Cities. His work is also featured in Design with Nature Now.

A core tenet of Yu’s overall approach is a concept he calls fan guihua. The concept is frequently translated as “negative planning,” but might be more accurately rendered as “inverse planning.” It’s essentially a counter to the type of development that has shaped China’s growth for so long. “You plan what’s not built,” Yu explains. “You plan what should be protected.”

This, obviously, is a fairly radical idea in contemporary China. Yet in the course of his work, Yu came to a surprising realization: the idea of living with water, rather than battling it, was a concept that had historically been very familiar. In central and southern coastal China, including the area where Shenzhen now stands, a distinctive method had evolved over centuries to catch rainfall and carefully manage it with earthen dikes to raise mulberries, silkworms, and fish, a sort of landscape-scale aquaponics system. And when Yu and his students looked deeper, they realized that sponge city-like concepts had been a fundamental principle of Chinese city planning for centuries. Traditionally, he says, many Chinese cities had the capacity to absorb two-thirds of local rainfall within their boundaries.

With this discovery, the idea of a different way of managing water—and the perils of a drastically altered hydrologic cycle—became a major theme of Yu’s work. Nature, for its part, began putting an increasingly fine point on the issue. During the 2012 flood in Beijing, “seventy-nine people were killed. Drowned. On the street,” Yu says. “In the capital, we drowned 79 people. How is that possible? We lost face. That immediately became a political issue.”

Yu wrote another letter to high-level leaders saying that adopting the sponge city approach and creating a resilient landscape might offer hope. As it happens, Xi Jinping had recently become the secretary general of the Communist Party and president of China. After decades of the country struggling with notorious pollution and other environmental problems, Xi has staked his reputation on creating an “ecological civilization” in China.

The exact contours of that concept are sometimes difficult to discern, but in broad outline it encompasses both a nationwide push for ecological sustainability and the creation of a green, uniquely Chinese alternative development model for the rest of the world. Both sponge city thinking and a more expansive embrace of low-impact development fall squarely within Xi’s larger aspirations.

“China’s in an environmental crisis. We have to do this,” Yu says. “When people can’t breathe, when the water is polluted—I think he’s very sensitive to those issues. I think he really wants to build his legacy on doing this.”

The biggest challenge to making sponge cities work on a broad scale has nothing to do with building rain gardens, installing permeable pavement, or placating neighbors. “Finance is a major issue,” says Liu.

Liu, who came to the Lincoln Institute after 18 years with the World Bank, is largely focused on governance and financing issues associated with land use in China. Taking the sponge city concept to scale won’t be easy, and he cites the challenges in Shenzhen as an example. Sponge city improvements in Shenzhen, which officially began in 2017, now cover 24 percent of the city’s total surface area. The government has a goal of increasing that to 80 percent by 2030. But hitting that target will be a significant challenge.

The central government has pledged a total of $5.8 billion (40 billion Chinese yuan) to incentivize Shenzhen and the 29 other pilot cities to invest in and carry out sponge city work. But it wants each of those places to bring at least 20 percent of its developed area up to the sponge city standard by the end of this year.

Liu says that bringing a square kilometer of already developed urban land up to the standard typically costs $22 million to $29 million (150 to 200 million CNY). The 30 pilot cities are each eligible for 400 to 600 million Chinese yuan per year from the central government for three years. That’s enough to upgrade, at most, four square kilometers per year. To meet—and actually exceed—the central government’s 20 percent by 2020 target, Shenzhen brought about 235 square kilometers up to standard, at a cost that likely ran anywhere from $5 billion to $7 billion.

“Asking the municipal government to come up with that kind of money is not easy,” Liu says. Shenzhen was able to pull it off because of its strong municipal budget and private commitments from the city’s tech and manufacturing giants. But, he adds, “if you go to the interior cities where the municipal finance is very weak, it’s very difficult.”

Liu points out that in the case of new development, cities can implement standards that will require developers to pay for improvements, a cost typically passed on to residents and firms. “If you look at the upfront costs for development, sponge cities are not a very expensive thing to do,” Liu says. Retrofitting existing development, however, is a much bigger challenge.

“The toughest issue is that public finance is used to finance the public good, with very little opportunity for cost recovery,” he continues. “That’s really the toughest story about China. It’s a matter of priority. The cities just have too much on their plate. So by the end of the day, very few cities can find enough money.”

Sponge city infrastructure is “just like a streetlight,” Liu says. “It’s a shared public good, but nobody wants to pay for it.”

In truth, the biggest challenge of turning the sponge city into reality may well be unraveling the financing mechanics. Yet the cost of not rising to the challenge may be higher than anyone fully appreciates.

“It’s really like thinking about buying insurance,” Liu says. “We are all facing uncertainties, but the trend of more intense storms is quite clear . . . The cost of inaction might not look that high today, but when we’re faced with a catastrophic outcome in 10 or 20 years, we’ll regret that we didn’t spend the money earlier.”

Even given those high stakes, the sponge city idea could ultimately be about even more. Back in Shenzhen, standing on the roof of the apartment building in Gangxia, TNC’s Yu says sponge cities do a lot more than tame floods and save water for dry seasons. 

“If you only talk about stormwater management or runoff control, the average person won’t necessarily buy in, because they’ll feel like it doesn’t have any connection to them,” he says. “But features like green rooftops are different. They can have a synergistic effect. They help absorb rainfall, but they also improve the neighborhood view, contribute to urban biodiversity, and create a green space that everybody can use.”

Matt Jenkins, who has previously worked as an editor for Nature Conservancy magazine, is a freelance writer who has contributed to The New York Times, Smithsonian, Men’s Journal, and numerous other publications.

Photographs (in order of appearance):

Shenzhen, China, is one of 30 pilot “sponge cities” in China that are investing in nature-based stormwater management solutions. Credit: Wang Jian Xiong via Flickr CC BY 2.0.

Xiangmi Park, also known as Honey Lake Park, is a former agricultural research area in Shenzhen that was redesigned for community use. Bioswales, permeable pavement, and other elements allow it to double as a stormwater management tool. Credit: Vlad Feoktistov.

Rooftop garden on the Tencent Binhai towers in Shenzhen. Tencent founder and CEO Pony Ma is an advocate of sponge cities who has inspired fellow business leaders to invest in nature-based solutions in Shenzhen. Credit: The Nature Conservancy/Theodore Kaye.

Aún no me recupero de la experiencia de estudiar economía en el posgrado; allí, el saber general era que ciertos desafíos no pueden resolverse. Por ejemplo, una de las primeras lecciones fue que ningún sistema de votación puede llegar con fiabilidad a la “decisión correcta” que satisfaga una serie de principios básicos. Kenneth Arrow, Premio Nobel, demostró que ningún método de votación es justo, y que el único que no tiene fallas es la dictadura. Mediante el relato apócrifo de la “Tragedia de los bienes comunes”, aprendí que el acceso no restringido a los recursos comunes siempre terminará en el uso excesivo y la destrucción de dichos recursos. También aprendí que la acción colectiva por el bien común no tiene buenos resultados si involucra a más de siete personas. No es broma.

En mi camino de recuperación, detecté una falla en la secuencia adoptada por los economistas para analizar problemas. Primero, observamos la teoría para enmarcar la respuesta, y luego buscamos aplicar la estructura teórica para resolver la dificultad. Comenzamos con suposiciones que parecen razonables acerca de la conducta racional humana, como que la gente siempre prefiere más en vez de menos cuando se trata de algo bueno; si un votante prefiere al candidato A por sobre el B, y al B por sobre el C, entonces debe preferir al A por sobre el C (transitividad). Luego, construimos la dificultad en sí como una serie de elecciones hechas por agentes racionales. Inevitablemente, la teoría nos dice que algunas dificultades son insalvables, y que es imposible obtener una solución óptima. No importa cómo se computan los votos, siempre se encuentra un caso en que los votantes violan la transitividad de forma colectiva. Ya que más es mejor, los pastores pastarán de más y destruirán los bienes compartidos de pastoreo porque aumentarán el tamaño de su rebaño.

Pero, gracias a las palabras de dos filósofos más prácticos del s. XX, pude ver las cosas de otro modo: “En teoría, no hay diferencia entre práctica y teoría. En la práctica, sí” (atribuido a Yogi Berra); y “Una disposición de recursos que funciona en la práctica puede funcionar en la teoría” (conocido como Ley de Ostrom). Berra era un receptor de béisbol bajo y fornido que podía darle a todo lo que le lanzaban; y casi nunca lo eliminaban. Lo votaron como jugador más valioso de la liga tres veces y tiene el récord de cantidad de equipos con campeonatos mundiales. Elinor Ostrom, la primera mujer que ganó un Premio Nobel de economía, dedicó su carrera a demostrar cómo los grupos grandes de individuos que usan un recurso en común, como la pesca, encuentran formas de administrar la sustentabilidad de dicho recurso.

Resulta que muchas de las dificultades que los economistas consideran irresolubles también son existenciales. Tal vez la mejor forma de resolverlas sea probar cosas hasta encontrar algo que funcione. Uno de los mejores ejemplos, y de los más efectivos, de entrar en acción antes de ajustar todas las tuercas y tornillos teóricos es el Protocolo de Montreal (y también es un modelo potencial para abordar otros problemas mundiales complejos).

En la década de 1970, la gente empezó a notar que la capa de ozono de la atmósfera superior se estaba reduciendo en los polos, y en particular en la Antártida. La capa de ozono es lo que da el color azul al cielo. También permite que exista la vida en la tierra, porque absorbe la radiación ultravioleta nociva del sol. Poco más de una década después, los científicos concluyeron que la culpa recaía en la emisión de clorofluorocarbonos y otras sustancias que agotan la capa de ozono (SAO), compuestos artificiales para refrigeración, gases propelentes y materiales para la producción de plásticos, como el poliestireno extruido. El uso de SAO era extendido e iba en aumento, y la industria química no tenía alternativas ni una voluntad particular para desarrollarlas. Se hizo evidente que se necesitarían acciones a escala global para abordar la crisis de ozono, motivar a la industria para encontrar alternativas a estos químicos nocivos, convencer a todos los países posibles de que prohibieran el uso e hicieran cumplir la prohibición, y recolectar y reemplazar las SAO en refrigeradores e industrias existentes.

Los obstáculos parecían ser insuperables. Los voceros industriales popularizaron la “negación del ozono”: “¿Cómo llegan a 15.000 metros de altura los gases propelentes de mi desodorante, que se emiten a nivel del mar?”. “¿Cómo llegan a los polos las SAO emitidas en Topeka?”. Los científicos elaboraron respuestas a estas preguntas, convincentes, pero no definitivas: tormentas y circulación global. Pero con el aumento de la preocupación pública pasó algo extraordinario: incluso sin certezas científicas, los gestores de políticas, ambientalistas, científicos y líderes industriales decidieron que los riesgos que presentaba la disminución de la capa de ozono eran tan graves que ameritaban tomar precauciones.

En 1987, 46 países firmaron el Protocolo de Montreal para proteger la capa de ozono mediante la eliminación gradual de la producción y el consumo de SAO. Este entró en vigencia dos años después, y la implementación fue flexible y práctica. Dado que esta ciencia era emergente, los signatarios decidieron basar las futuras decisiones políticas en evaluaciones periódicas hechas por paneles de expertos mundiales en ciencias, medioambiente y economía. Para lograr que se unieran los 151 países restantes, los signatarios acordaron comerciar solo con otros signatarios. Enseguida adhirieron todos los países.

Para países de ingresos más bajos, sin los recursos necesarios para reemplazar las SAO, la implementación no fue punible. Se pidió a los países no cumplidores que trabajaran con un organismo de la ONU para preparar planes de acción y ponerse al día con el cumplimiento del Protocolo. En 1991, se fundó el Fondo Multilateral, por el que los países más ricos ofrecieron unos US$ 4.000 millones para ayudar a los de menores ingresos a cumplir con lo pactado. Hacia 2010, los 142 países signatarios en desarrollo lograron eliminar las SAO por completo.

El Protocolo de Montreal fue el primer tratado de la ONU de la historia en lograr ratificación universal. Esto demuestra que, a pesar de la teoría económica, es posible hallar soluciones colectivas a dificultades que parecen no tener solución. También demuestra algo particularmente crucial para estos tiempos: podemos afrontar las dificultades ambientales globales más complejas de forma efectiva y cabal. Las preocupaciones por la disminución de la capa de ozono pasaron de ser un problema ambiental periférico a ser impulsoras de cooperación nacional e internacional sin precedentes. Para este año, se eliminó gradualmente el 98 por ciento de las SAO incluidas en casi 100 químicos peligrosos del mundo. Los 197 signatarios cumplen con el Protocolo. Según las proyecciones, la capa de ozono volverá a los niveles de 1980 entre 2045 y 2065.

Un beneficio imprevisto del Protocolo de Montreal es la protección climática que ya logró. Al quitar de la atmósfera algunos de los gases de efecto invernadero más poderosos, el aporte del tratado para mitigar el cambio climático es mayor que el primer objetivo de reducción global del Protocolo de Kioto, centrado en el clima. Este último fue una extensión de un marco mundial establecido en 1992 para evitar la interferencia humana “peligrosa” en el sistema climático. Dicho marco, la Convención Marco de Naciones Unidas sobre el Cambio Climático (CMNUCC), propuso un objetivo simple: reducir la emisión de gases de efecto invernadero de todos los sectores para que el calentamiento global sea inferior a 2 ºC. Al igual que el Protocolo de Montreal, fue ratificado por 197 países y se basa en un panel de investigadores expertos para guiar y adaptar las respuestas políticas. Pero el cambio climático es mucho más complejo y polémico que proteger la capa de ozono. Hasta ahora, este marco no ha sido tan eficaz como el Protocolo de Montreal ni por asomo; si el aumento de la preocupación pública y los virajes políticos cambiarán esto, aún está por verse.

En 2000, luego de adoptar la Declaración del Milenio de las Naciones Unidas, se establecieron Objetivos de Desarrollo del Milenio (ODM) para todos los estados miembro. La declaración manifiesta que todas las personas tienen derecho a libertad, igualdad y un estándar de vida básico que incluye ser libre de hambre y violencia. Los ODM establecieron ocho metas específicas que se debían alcanzar para 2015 a fin de reducir la pobreza en todos los países, y hubo algunos logros: los estados miembro alcanzaron tres de las ocho metas, e hicieron grandes avances en cuatro de las cinco restantes. Para ayudar a los países en desarrollo a alcanzar las metas, los países desarrollados acordaron cancelar unos US$ 50.000 millones de deuda de los países pobres con deudas importantes.

En 2015, la ONU desarrolló una serie de Objetivos de Desarrollo Sustentable (ODS) para alcanzar los ODM. Los ODS son el marco político global más complejo hasta hoy, e incluyen 17 metas globales diseñadas para “lograr un futuro mejor y más sustentable para todos”. Un marco de informes obliga a los 193 estados miembro ratificantes a informar los progresos en 169 objetivos y 232 indicadores aprobados. Los ODS demuestran labores incluso más ambiciosas para trabajar de forma colectiva y abordar las dificultades globales.

Si bien estos marcos de políticas globales han triunfado en distintas medidas, tienen elementos importantes en común: reconocen el problema; en general, concuerdan en las causas y las soluciones; tienen metas idealistas, pero específicas; obligan a los países desarrollados a llevar la delantera (a veces, con recursos); poseen estructuras de monitoreo y evaluación; y, en los mejores casos, son acuerdos vinculantes que definen el cumplimiento e incluyen informes obligatorios.

Gracias al cielo, los economistas no se encargaron del diseño de dichos marcos. Todavía estaríamos esperando el marco teórico para las labores colectivas, antes de que pudiéramos empezar con la implementación. Por suerte, gente más pragmática se dio cuenta de que encontrar una solución estructural que satisfaga una serie de principios predeterminados es menos importante que actuar para superar una dificultad existencial y afrontar los obstáculos a medida que aparecen.

En el Instituto Lincoln, adoptamos un enfoque similar para cumplir nuestra misión global. El marco guía, nuestro Camino hacia el Impacto, ilustra nuestra estrategia para abordar seis desafíos sociales, ambientales y económicos con el uso de políticas de suelo. Establecimos objetivos a mediano plazo, y pronto identificaremos una serie de referencias con las cuales podemos hacer un seguimiento de los logros. En los próximos meses, alinearemos los objetivos y las referencias con los ODS correspondientes. Así, demostraremos nuestro compromiso y aporte para un futuro mejor y más sustentable para todos. También reconocemos que nuestro trabajo de campo no siempre se alineará con los objetivos estratégicos mejor elaborados, y estamos trabajando para mantener una flexibilidad suficiente para hacer frente a los obstáculos que surjan. Si algo aprendí es que la práctica hace imperfecta a la teoría, y que eso es bueno.

Fotografía: El Protocolo de Montreal es un marco global vigente de políticas con el cual 197 naciones tratan amenazas a la capa de ozono. Aquí, los representantes se reúnen en la sesión de apertura en la 28.º reunión de partes según el protocolo, en 2016. Crédito: Ministerio de Ambiente, Ruanda/Flickr CC BY 2.0.

I’m still recovering from studying graduate-level economics, where the going wisdom was that certain challenges are insoluble. An early lesson, for example, was that no voting system can reliably reach the “right decision” that satisfies a set of basic principles. Nobel laureate Kenneth Arrow showed that no voting method is fair, and that the only voting method that isn’t flawed is dictatorship. I learned through the apocryphal tale of the Tragedy of the Commons that ungov­erned access to common resources will always end in the overuse and destruction of those resources. I also learned that collective action to produce public good could not succeed if it involved more than seven people. I’m not kidding.

As I recover, I’ve detected a flaw in the sequence adopted by economists to break down problems. We look first to theory to frame our response, then seek to apply the theoretical structure to resolve the challenge. We begin with seemingly reasonable assumptions about rational human behavior, e.g., people always prefer more rather than less of a good thing; if a voter prefers candidate A over candidate B and candidate B over candidate C, then the voter must prefer candidate A over candidate C (transitivity). We then construct the challenge itself as a set of choices made by rational agents.

Inevitably, theory tells us that some challenges are insurmountable, and optimal resolution is impossible. No matter how we tally votes, we can always find a case where voters will collectively violate transitivity. Because more is better, pastoralists will overgraze and destroy shared grazing commons by increasing the size of their herds.

But the words of two more practical 20th-century philosophers have helped me see things differently: “In theory, there is no difference between practice and theory. In practice, there is” (attributed to Yogi Berra); and, “A resource arrangement that works in practice can work in theory” (commonly known as Ostrom’s Law). Berra was a short, stocky baseball catcher who would swing at anything thrown near him—and almost never struck out. He was voted league MVP three times and played on more world champion teams than any other player. Elinor Ostrom, the first woman to win the Nobel Prize in Economics, spent a career showing how large groups of individuals who use a common resource, like a fishery, find ways to steward the resource sustainably.

As it turns out, many of the challenges eschewed by economists as insoluble are also existential. Maybe the best way to solve them is to try things out until we find something that works. One of the best and most effective examples of taking action before all the theoreti­cal nuts and bolts were firmly in place—and a potential model for addressing other complex global issues—is the Montreal Protocol.

In the 1970s, people started noticing that the ozone layer of the upper atmosphere was thinning out over the poles—especially over Antarctica. The ozone layer makes the sky blue. It also makes life on earth possible by absorbing harmful ultraviolet radiation from the sun. After a little more than a decade, scientists concluded that the culprit was the release of chlorofluoro­carbons and other ozone-depleting substances (ODS), artificial compounds used as refrigerants, aerosol propellants, and inputs in the production of plastics like Styrofoam. ODS use was ubiqui­tous and growing, and the chemical industry did not have—and was not particularly willing to develop—alternatives. It became clear that action on a global scale would be required to address the ozone crisis, motivating industry to find alternatives to these harmful chemicals, persuading as many countries as possible to ban their use and enforce the bans, and collecting and replacing ODS in existing refrigerators and industrial stocks.

The obstacles seemed insurmountable. Industry spokespeople popularized “ozone denial”: “How do propellants from my deodorant, sprayed at sea level, get to altitudes of 50,000 feet?” “How do ODS released in Topeka make it to the poles?” Scientists produced compelling, but not definitive, answers to these questions, in the form of things like thunderstorms and global circulation. But as public concern grew, something extraordinary happened: even without scientific certainty, policy makers, environmen­talists, scientists, and industry leaders decided that the risks posed by ozone depletion were severe enough to warrant precaution.

In 1987, 46 countries signed the Montreal Protocol to protect the ozone layer by phasing out the production and consumption of ODS. It took effect two years later, and its implementa­tion was adaptive and practical. Because the science was emerging, signatories decided to base future policy decisions on periodic assessments by panels of worldwide experts in science, the environment, and economics. To get the other 151 countries in the world to join, signatories agreed to trade only with other signatories. It didn’t take long before all countries signed on.

For lower-income countries without the resources needed to replace ODS, compliance enforcement was non-punitive. Wayward countries were asked to work with a UN agency to prepare action plans to get back into compliance. In 1991, the Multilateral Fund was established, with wealthier countries providing around $4 billion to help lower-income countries meet their commit­ments. By 2010, all 142 developing country signatories had completely phased out ODS.

The Montreal Protocol was the first UN treaty in history to achieve universal ratification. It proves that, economic theory to the contrary, collective solutions to seemingly insurmountable challenges are possible. It also proves something especially critical for our current times: we can effectively and comprehensively tackle our most complex global environmental challenges. Concerns over ozone depletion evolved from a fringe environmental issue to a driver of unprece­dented national and international cooperation. As of this year, 98 percent of ODS contained in nearly 100 hazardous chemicals worldwide have been phased out. All 197 signatories are in compliance. Projections show that the ozone layer will return to 1980 levels between 2045 and 2065.

One unanticipated benefit of the Montreal Protocol is the climate protection that it has already achieved. By removing some of the most powerful greenhouse gases from the atmos­phere, the treaty’s contribution to climate change mitigation is larger than the first global reduction target of the climate-focused Kyoto Protocol. The latter was an extension of a global framework established in 1992 to prevent “dangerous” human interference with the climate system. That framework, the United Nations Framework Convention on Climate Change (UNFCCC), proposed a simple goal: to reduce greenhouse gas emissions from all sectors to keep global warming below 2 degrees Celsius. Like the Montreal Protocol, it has been ratified by 197 countries and relies on an expert research panel to guide and adjust policy responses. But climate change is far more challenging and contentious than protecting the ozone layer. So far, this framework has not been nearly as effective as the Montreal Protocol; it remains to be seen whether increasing public concern or shifting political winds will change that.

In 2000, following the adoption of the United Nations Millennium Declaration, global Millennium Development Goals (MDGs) were established for all member states. The declaration stated that all people have the right to freedom, equality, and a basic standard of living that includes freedom from hunger and violence. The MDGs established eight specific targets to be achieved by 2015 for poverty reduction in all countries, and met with some success: member states achieved three of the eight targets, and made significant progress on four of the other five. To help less developed countries achieve the goals, developed countries agreed to cancel around $50 billion of debt for heavily indebted poor countries.

In 2015, the UN developed a set of Sustaina­ble Development Goals (SDGs) to succeed the MDGs. The SDGs, the most complex global policy framework to date, include 17 global goals designed to “achieve a better and more sustain­able future for all.” A reporting framework binds the 193 ratifying member states to report on progress on 169 targets and 232 approved indicators. The SDGs reveal ever more ambitious efforts to work collectively to address global challenges.

Though these global policy frameworks have attained varying levels of success, they share important common elements: recognition of the problem; general agreement on causes and remedies; lofty but specific goals; an onus on developed countries to lead the way (sometimes with resources); monitoring and evaluation structures; and, in the best cases, binding agreements that define compliance and include mandatory reporting.

Thank goodness economists didn’t take the lead in the design of these frameworks. We would still be waiting for a theoretical frame­work for our collective efforts before we could begin implementation. Luckily, more pragmatic people realized that finding a structural solution that satisfies a set of predetermined principles is less important than taking action to overcome an existential challenge, addressing obstacles when they are encountered.

At the Lincoln Institute, we have adopted a similar approach to achieve our global mission. The guiding framework, our Pathways to Impact, illustrates our strategy for addressing six global social, environmental, and economic challenges using land policy. We have articulated medium-term objectives and will soon identify a set of benchmarks through which we can track our success. In the coming months, we will align our objectives and benchmarks with the appropriate SDGs. This will show both our commitment and our contribution to a better and more sustainable future for all. We also recognize that our work on the ground won’t always align with even the most well-crafted strategic goals, and we are working to remain flexible enough to meet obstacles as they arise. If there’s one thing I’ve learned, it’s that practice makes theory imperfect—and that’s a good thing.

George McCarthy is president and CEO of the Lincoln Institute of Land Policy.

Photograph: The Montreal Protocol is an effective global policy framework that has led197 nations to address threats to the ozone layer. Here, representatives gather for the opening session of the 28th meeting of the parties to the protocol in 2016.  Credit: Ministry of Environment, Rwanda/Flickr CC BY 2.0.

Jane Difley, a forester and conservation pioneer who led the Society for the Protection of New Hampshire Forests (the Forest Society) for 23 years, has been named the new Kingsbury Browne Fellow at the Lincoln Institute of Land Policy and the recipient of the Kingsbury Browne Conservation Leadership Award from the Land Trust Alliance (LTA).

Difley, who served as an intern with the Forest Society in graduate school, returned to lead the organization in 1996, doubling the size of its conserved Forest Reservations to 56,000 acres during more than two decades as president. Under her leadership, the Forest Society played a pivotal role in the creation of the Land and Community Heritage Investment Program (LCHIP), a state authority that supports the conservation and preservation of New Hampshire’s natural and cultural resources. LCHIP has since made 240 grants to land conservation and historic preservation projects in 141 communities across the state, protecting a total of 260,000 acres and 142 historic structures in the process. Difley retired from the organization this fall. (Listen to an extensive New Hampshire Public Radio interview with Difley about the shifts she has observed in land conservation and forest management throughout her career.)

Before her tenure at the Forest Society, Difley served as executive director of the Vermont Natural Resources Council and as vice president of forestry programs and national director of the American Tree Farm system at the American Forest Foundation. She was the first woman to serve as the president of the Society of American Foresters.

“Jane Difley has had a remarkable career as a pioneering leader in conservation. She is certainly beloved in New Hampshire, where she served at the helm of the Society for the Protection of New Hampshire Forests for the past 23 years,” said Jim Levitt, who leads the Lincoln Institute of Land Policy’s land conservation efforts. “Under her leadership, the Forest Society has helped to protect about 300,000 acres, its epic advocacy efforts to block a major transmission line through the heart of the state has succeeded, and it continues to be a leading force for conservation education from Nashua to the Canadian border.”

The Kingsbury Browne fellowship and award, given since 2006, are named for Kingsbury Browne, a Boston tax lawyer and conservationist who served as a Lincoln Fellow in 1980 and helped to form the LTA in 1982. Difley was officially recognized at Rally 2019, the LTA’s annual gathering of land conservation professionals, held in October in Raleigh, North Carolina. During 2019–2020, Difley will engage in research, writing, and mentoring at the Lincoln Institute.

Previous recipients of the fellowship include Michael Whitfield, executive director of the Heart of the Rockies Initiative, who has built partnerships among landowners, civic leaders, government officials, and scientists to protect iconic landscapes in the Rocky Mountain West; Will Rogers, head of The Trust for Public Land; David Hartwell, an environmental leader who has helped mobilize billions of dollars for conservation projects across Minnesota; Steve Small, a legal pioneer who paved the way to make conservation easements tax-deductible in the U.S.; Jean Hocker, a former president of the LTA and longtime board member at the Lincoln Institute; Larry Kueter, a Denver attorney specializing in agricultural and ranchland easements in the West; Peter Stein, managing director of Lyme Timber Company; Audrey C. Rust, president emeritus of the Peninsula Open Space Trust based in Palo Alto, California; Jay Espy, executive director of the Elmina B. Sewall Foundation; Jamie Williams, president of The Wilderness Society; Laurie A. Wayburn, cofounder of the Pacific Forest Trust; Mark Ackelson, president of the Iowa Natural Heritage Foundation; and Darby Bradley, president of the Vermont Land Trust. 

About the Lincoln Institute

The Lincoln Institute of Land Policy seeks to improve quality of life through the effective use, taxation, and stewardship of land. A nonprofit private operating foundation whose origins date to 1946, the Lincoln Institute researches and recommends creative approaches to land as a solution to economic, social, and environmental challenges. Through education, training, publications, and events, we integrate theory and practice to inform public policy decisions worldwide. For more information visit www.lincolninst.edu.

About the Land Trust Alliance

Founded in 1982, the Land Trust Alliance is a national land conservation organization that works to save the places people need and love by strengthening land conservation across America. The Alliance represents 1,000 member land trusts supported by more than 200,000 volunteers and 4.6 million members nationwide. The Alliance is based in Washington, D.C., and operates several regional offices. More information about the Alliance is available at www.landtrustalliance.org.

Photograph Credit: Land Trust Alliance.

With climate change posing imminent risks that range from rising seas to more extreme weather events, cities must work with ecology rather than against it to develop sustainably, according to the new book Design with Nature Now (available here). Urban design that values natural systems can help us confront the most serious environmental challenges of this century, says the book, released this month by the Lincoln Institute of Land Policy and the University of Pennsylvania Stuart Weitzman School of Design.  

Timed to coincide with the 50th anniversary of pioneering landscape architect Ian McHarg’s influential manifesto Design with Nature, the new volume features more than 160 color images that illustrate 25 cutting-edge projects that address biodiversity loss, sea-level rise, water and air pollution, and urbanization. These instructive interventions include a park on the site of a New York City landfill that once accepted 29,000 tons of refuse a day; a wetland in China constructed to filter pollution from a planned city of 50,000 people; a proposal for built landforms in coastal Norfolk, Virginia, that would absorb stormwater and tides; and an ambitious concept for a wind turbine farm in the North Sea.  

Featuring essays and analysis from leaders in the field of ecological planning, design, and landscape architecture, Design with Nature Now pays tribute to McHarg’s philosophy and impact while demonstrating the continued relevance of his work for a swiftly changing era.  

“Design with Nature Now reminds us of the urgency that led Ian McHarg to write his seminal work—and the unavoidable fact that, in many ways, that urgency has only increased,” said George W. “Mac” McCarthy, president of the Lincoln Institute of Land Policy. “With urbanization occurring rapidly and climate change demanding that we rethink nearly everything about where and how we live, McHarg’s ideas are more apt than ever.” 

The book features insights from leading practitioners behind renowned contemporary public works, including James Corner, project lead for New York City’s celebrated High Line Park; Anne Whiston Spirn, who has spearheaded an effort to restore nature and rebuild community in West Philadelphia; and Laurie Olin, whose projects include the master plan for the Los Angeles River and the design of Manhattan’s Bryant Park. It also offers a behind-the-scenes look at the roots of geographic information system (GIS) technology—McHarg is broadly credited with developing the concept behind the widely used planning tool—and compelling evidence that thoughtful design principles can help combat climate change.

McHarg drew new connections between ecology and cities in the 1960s and helped to create the multidisciplinary field of ecological planning. Today, the Ian L. McHarg Center for Urbanism and Ecology at the University of Pennsylvania brings environmental and social scientists together with planners, designers, policy makers, and communities to develop practical, innovative ways of improving the quality of life in the places most vulnerable to the impacts of climate change. The editors of Design with Nature Now, who are McHarg’s successors at the University of Pennsylvania, affirmed the importance of his principles in the climate change effort.  

“We are plunging, headlong, into an epoch of global environmental change at an unprecedented scale and pace,” write editors Frederick Steiner, Richard Weller, Karen M’Closkey, and Billy Fleming in the introduction to the book. “How we learn to live with that change is the central challenge for the next half-century of design. In the work we have collected here there are real clues as to how, through design, we can better tune our cities and their infrastructure to the forces and flows of the Earth system.”  

Reflecting on McHarg’s legacy and on the impact of the new book, author and activist Bill McKibben said, “Ian McHarg would be heartened to see the range and quality of thinking he’s inspired. Each of these essays will leave you with an enlarged sense of possibility, which is a great gift in a constrained world.” 

Bruce Babbitt, former U.S. Secretary of the Interior and former board member of the Lincoln Institute, also weighed in, noting, “This exceptional book presents the enduring wisdom of Ian McHarg to a new generation. His insights, freshly interpreted in the pages of landscape designs and drawings, give me hope for the future of our planet.” 

To learn more or to order a copy of Design with Nature Now, visit: https://www.lincolninst.edu/publications/books/design-nature-now.

Photograph Credit: Shenmin Liu.