Do We Need Another Green Revolution?
“Carbon farming and vertical farming are wildly overhyped,” Grunwald concludes. “Plant-based meat has floundered in the market, while cultivated meat hasn’t really made it to market.” He adds, “I’m sorry about all that.”
Grunwald is an engaging storyteller, and, to his credit, he sticks with the “terrible math” even as it turns terribler and terribler. A reasonable takeaway from “We Are Eating the Earth” is that the feeding-without-frying equation is the sort that can be solved only with imaginary numbers.
In the absence of breakthroughs, what’s to be done? A good first step, Grunwald counsels, would be to stop making things worse. We could start with biofuels. Every year in the United States, some fourteen billion gallons of so-called conventional ethanol—most of which are produced from corn—get blended into gasoline. The practice is federally mandated, and one of the justifications for the policy is that it’s supposed to reduce greenhouse-gas emissions. Almost certainly, though, it has the opposite effect. Diverting corn from grocery stores to gas tanks pushes up commodity prices—which, in turn, encourages farmers to convert forests and marshes into cropland. Since forests and marshes store a lot of carbon, cutting down or draining them increases atmospheric CO₂. Higher commodity prices also, of course, pose more immediate problems, especially for the world’s poor. Grunwald quotes an anti-ethanol protest song by the Jamaican reggae singer Livebroadkast:
Another ostensibly green idea that needs rethinking, according to Grunwald, is organic farming. Reducing fertilizer and pesticide use, raising cattle on grass instead of grain—these may sound like community-minded, environmentally friendly options. But if such practices diminish yields—and Grunwald argues convincingly that they do—then they’re the reverse. To hold the globe’s food supply steady, not to mention increase it, any drop in one farm’s output has to be made up somewhere else. And that somewhere may well turn out to be a field cut out of a rain forest.
It’s “trendy to romanticize small family farms where soil is nurtured with love and animals have names rather than numbers,” Grunwald writes. But “organic, local, and grass-fed are often worse for the climate than conventional, imported, and feedlot-finished.” Grunwald travels to Denmark and Brazil with Tim Searchinger, a researcher at Princeton who has written extensively on the climate impacts of agriculture. “Bad accounting destroys the world,” Searchinger tells him.
Vaclav Smil is a professor emeritus at the University of Winnipeg and the author of more than forty books, several of which also focus on farming. “How to Feed the World” is a typical Smilian work in that it is dense, declarative, and dismissive of lots of other work. “Over the past decade I have been repeatedly exasperated by people’s poor understanding and sheer ignorance of life’s many basic realities, be they concerning organisms or machines, crops or engines, food or fuels,” he writes.
In his introduction, Smil waves aside climate change, saying that he is not going to take up such “fashionable topics.” Nevertheless, he, too, worries about agriculture’s ecological impact. The global food system, he observes, needs to “accommodate the nearly 2 billion people that will be added to today’s population by the middle of the 21st century” at the same time that it needs to “reduce its multitude of environmental burdens.”
Smil is a number cruncher. His premise is that he doesn’t need to visit laboratories or sample ice cream to know what is going to work—and, just as important, what isn’t. Take lab-grown meat. Such meat is produced in bioreactors, which are sterile vats filled with a growing medium. Bioreactors are widely used in drug manufacturing. Smil calculates that to grow just one per cent of the globe’s current meat output would require something like a hundred times the bioreactor capacity of the world’s entire pharmaceutical industry. “Ambitions and aspirations are one thing, realities another,” he writes.
Or consider efforts to improve on photosynthesis. Photosynthesis is woefully inefficient—even some of the most productive crops convert less than one per cent of the solar energy that hits them into calories—so streamlining the process, via gene editing, could produce significant gains. But Smil is skeptical that this can actually be accomplished. Photosynthesis has been around for hundreds of millions of years and is phenomenally complicated. “Prospects for any early commercial breakthroughs” on this front are, in his view, “meager.”
The good news, according to Smil, is that breakthroughs aren’t necessary. The world could go a long way toward keeping up with food demand simply by better managing the supply. A report commissioned by the Food and Agriculture Organization of the United Nations estimates that, globally, about forty per cent of fruits and vegetables, thirty per cent of cereal grains, and twenty per cent of meat and dairy products wind up uneaten. The problem is worst in affluent countries like the U.S., where more than two hundred pounds of food per person get thrown away each year. “Even modest food waste reductions would translate into considerable cumulative savings,” Smil observes.
Then, there’s the waste that results from improvident eating habits. If photosynthesis has a low conversion rate, feeding crops to animals compounds the problem many times over. According to Smil, corn “embodies” about 0.7 per cent of the solar energy that hits it; when corn is used as cow fodder, the resulting steaks embody only about 0.002 per cent of the original energy. Pigs and chickens do better at turning grain into flesh. Still, producing a pound of pork or chicken takes many more resources than producing the same amount of, say, cornmeal. Reducing meat consumption, Smil argues, would be “both rational and highly desirable.”
Rates of meat-eating vary widely around the world. At the low end are countries like India and Ethiopia, where the average person consumes just thirteen pounds of meat per year. The U.S. lies at the upper end, weighing in at more than two hundred and sixty pounds per capita. Chinese rates of consumption are now also high—around a hundred and fifty pounds per person—after having doubled in just the past three decades.
Some of these differences reflect cultural and gastronomical traditions. But economics also plays a big—and ethically awkward—role. From a global perspective, the U.S. diet is too meat-heavy. But how do you get Americans to cut back, or the Chinese to hold steady? And how do you persuade any country to take on food waste? Smil offers a few possibilities, including measures to raise the price of groceries. Though he acknowledges that this would be unpopular, he says that this isn’t really his concern, as his book is “more interested in science than politics.” The strength of “How to Feed the World” is its emphasis on realism. How realistic is it, though, to leave politics out of the calculation?
When Norman Borlaug died, in 2009, at the age of ninety-five, his Times obituary praised him for having done “more than anyone else in the 20th century to teach the world to feed itself.” The Associated Press called him “equal parts scientist and humanitarian,” and MIT Technology Review described his life as one of “heroic proportions.” Were it not for Borlaug and the Green Revolution, the world in the late twentieth century would have been a very different place. Food prices probably would have been a lot higher, the number of people who are malnourished would have been greater, and even more millions of acres of forest would have been transformed into fields.
And yet, by the time of Borlaug’s death, his accomplishments were looking increasingly equivocal. The Green Revolution, critics pointed out, may have alleviated some problems, but it created additional ones, and these tended to impose the highest burdens on precisely those communities the new seeds were supposed to help.
Borlaug’s wheat varieties were highly productive. They were also fussy. They performed well only when showered with nutrients, pesticides, and water. This meant that the gains from planting them went disproportionately to those who could afford such “inputs”— which is to say, those farmers who were already relatively well off. The poorest farmers, for their part, often found themselves forced to sell out. Even if the Green Revolution reduced the price of a commodity like rice by sixty per cent, Raj Patel, a research professor at the University of Texas at Austin, has written that this would have been “little consolation” to those farmers who “lost 100% of their income.”
Increased water, pesticide, and fertilizer use, meanwhile, led to a host of environmental problems. In India, for example, the government encouraged farmers to irrigate their thirsty new crops by drilling into underground aquifers. Some thirty million so-called tube wells were sunk. Now, after several decades of pumping, many aquifers are running dry. According to a recent editorial in the Deccan Herald, “India is facing its worst groundwater crisis in history.” Adding to this crisis, much of the groundwater that remains is contaminated. A report issued last year by the Indian government found that twenty per cent of the samples taken from around the country contained unsafe levels of nitrates. (Nitrates in drinking water are particularly dangerous for infants, who can develop what’s known as blue-baby syndrome.) The report blamed the problem on “excessive use of fertilizers.”
In the eighty years since Borlaug arrived in Mexico, farming in much of the world has been transformed. New tools that could make farms even more productive are constantly being developed—from CRISPR to remote-sensing drones and weeding machines that shoot out lasers. At the same time, the world, too, has been transformed, by such things as climate change, groundwater depletion, and soil contamination. The new tools and the new threats are bound up in each other—two sides, as it were, of the same leaf. If it is reasonable to imagine that we will, somehow or other, find ways to feed ten billion people, it is also reasonable to fear how much damage will be done in the process. ♦
