And a growing number of consumers are clearly ready for change. “This is not a crisis-driven movement,” says Roberts. “It’s about authenticity and the concern that we don’t know where food is coming from. It’s part of a genuine re-evaluation.” He also credits the fact that there is increased disposable income for food and a large group prepared to pay. In addition, immigration growth has made an impact. “Most cultures in the world have not been so alienated from nature and from their own bodies,” he adds. “However low their income, they’ve come here with a reasonably high level of skill around cooking and a preference for fresh food and whole food.”

By far one of the most fantastical and massive concepts for the future of food came out of a medical ecology course at Columbia University in New York nine years ago. It began with the premise that if you damage the environment there will be health risks, and with the desire to do something locally that would have global implications. The idea has now been refined and reworked by eighty-two students; the first class focused on the possibilities of rooftop gardening in Manhattan.

Initial results were disappointing: the study identified thirteen acres of suitable rooftop in the city, with rice as the crop most likely to succeed — but that yield would feed a mere 2 percent of Manhattan residents. Dickson Despommier, a professor of public health, urged his students to move their operations inside, to reimagine abandoned apartment buildings, air force bases, empty lots. He coined the term “vertical farming” to help them visualize indoor spaces that could be converted to hydroponics, or aeroponics, a growing method that entails the constant spraying of suspended plants with nutrient-rich water.

While the idea of growing fruits and vegetables indoors on a massive scale may seem absurd, nasa scientists had already begun to research the potential of hydroponic vegetables, and Despommier’s students were able to use some of the information collected by the US space agency. As he says, it turns out there isn’t anything you can’t grow indoors — including a redwood tree. “You can control the growth characteristics; you can stack crops on top of each other. We began to look around and say, who’s doing this? The answer is nobody. Not a single person is growing food in tall buildings.”

There are myriad problems to work out in the prototype stage: how much water would be needed, how much and what kind of energy to use, and so on. Waste is an important issue, because if you don’t deal with this, Despommier says, then the structure is not viable, and it becomes a burden. In his vision, agricultural runoff doesn’t exist; black water (waste water containing biological effluent) and grey water (which contains no food or body waste) are purified by the plants and recycled. Furthermore, energy could potentially be derived from human waste. Each component of this plan exists now. “All are being done in small scales around the world. We have to pull them all together, put them under one roof.”

Already, several people have weighed in with fabulous, futuristic building designs, including Despommier, who designed one vertical farm that looks like an extraterrestrial pyramid. In his mind, the prototype might be four or five storeys tall (and would cost $20 million to $30 million to build). Once enough is known, potentially within a couple of years, the first full-scale version could be built: a thirty-storey building that would cost hundreds of millions of dollars and could theoretically feed 50,000 people. He acknowledges the risks associated with such centralization, but an argument could be made for having hospitals and schools — even individual apartment buildings — produce enough food to become self-sufficient.

Naturally, as a growing area is magnified, so is the potential for problems. Chief among them, of course, are pests, which in a vertical farm could potentially have a devastating impact. But Despommier thinks if plants are offered the same protection as patients suffer-ing from immunosuppression — that is, workers would go through the same drill as staff in a hospital or high-tech electronics factory — then a building could be made pest-and disease-free.

As for the energy needs of vertical farms, Despommier is considering a resource unlikely to be depleted: deriving power from human feces.

In an average year, he says, the bodily waste generated by 7.5 million New Yorkers could be converted into 900 million kilowatt hours of electricity. “What’s wrong with that? ” he says. “Not a goddamn thing.”His vision has generated interest among city officials across the US. Manhattan borough president Scott Stringer is putting together a feasibility study on vertical farming for the mayor of New York. Officials in Portland, Oregon, are pondering its potential. And in Seattle, a similar but smaller design for an urban agriculture centre won a green building contest in 2007; the proposal would grow grains, produce, and even chickens to provide a third of the food for the building’s 400 residents — all on a fraction of a hectare.

A similarly grand project, albeit on a smaller scale, has been quietly chugging away for a decade, two hundred kilo-metres north of the Arctic Circle. Behind Igloo Church, at the corner of Gwich’in Road and Breynat Street, is the Inuvik Community Greenhouse, the northernmost commercial hothouse on the continent. Since November 1998, the former hockey arena has been home to a variety of crops and flowers over two areas: a 12,000-square-foot community garden, where residents and local groups can tend to their own; and a 4,000-square-foot commercial greenhouse that pays for itself. Despite a relatively short season — mid-May to late September — eight weeks of non-stop sun intensifies the growth. Now residents of Inuvik, whose mean temperature is minus 9.7°C, have access to fresh local produce for as many months of the year as most of the rest of Canada.

Demand for Bryan Gilvesy’s beef is growing steadily. This year, he will process between forty and fifty animals; last year, he added fourteen heifers to his breeding herd; the year before, nine. He knows his market has room to expand, and he’s comfortable raising his prices. “We find our customers are motivated by a lack of trust in the mainstream food distribution system,” he explains. “They need to trust the quality of the food and the cleanliness of it [that it is hormone and antibiotic free], and they love to see that we care for the environment.” Hundreds of visitors have toured his farm to see how his operation works; other growers in the area are increasingly interested in farming more sustainably.

Slowly, slowly, things are starting to change. But the necessarily massive systemic overhaul is still far from a reality. “For every solution we’re trying, we have to battle against all sorts of regulations and impediments,” says Barbolet. “But if a transnational wants to bring in a genetically modified product, it gets subsidies. It’s ass backwards.” Nothing he and others envision will take fewer than twenty or thirty years, at best, to put in place. However, he says, “there’s no other choice.”