By Robert Turner
Bill Gates is a pretty smart guy. He’s one of those self-proclaimed science nerds who loves to read and study and learn new things.
So when he’s interested in something, it works to his advantage that people usually take his phone calls, including the top scientists at leading research institutions. He invests heavily in research and new technology, and he does his homework.
Gates’ recent book, How to Avoid a Climate Disaster (Knopf), is chock-full of the latest climate research and gives us a comprehensive look at the complicated issues and potential solutions to global warming. I recommend the book.
When most people think about solving climate change, they think about electricity, with wind and solar and electric cars. But that’s just a small piece of the larger, more complicated puzzle.
Gates organizes his book by all the human activities that produce greenhouse gases, putting them into five main categories: Making Things (building and manufacturing), 31 percent of greenhouse gases; Plugging In (electricity), 27 percent; Growing Things (agriculture), 19 percent; Getting Around (transportation), 16 percent; and Keeping Warm and Cool (heating, refrigeration), 7 percent. When you add the greenhouse gas emissions from the transportation of food to the growing of food, it becomes a bigger piece of the climate pie, and could approach 30 percent of global emissions.
In a chapter titled “How We Grow Things,” Gates tackles the impacts of agriculture on climate and what we can do to reduce carbon emissions in food production. And, while carbon dioxide is the main culprit for climate change in other chapters, in agriculture it’s methane—which causes 28 times more warming per molecule than CO2—and nitrous oxide, which causes 265 times more warming.
Climate-warming methane comes from cow burps and flatulence, and nitrous oxide comes from crop fertilizers. Fertilizing crops for animal feed is a double-whammy on climate.
Emissions from agriculture will continue to go up, says Gates, not just from feeding a growing global population expected to hit 9 billion by 2050, but from a world population that continues to climb out of poverty, and while getting richer, begins to eat more meat. As countries like China become wealthier, they can afford to consume more meat, and meat consumption rates are climbing quickly there.
Producing more meat and dairy will require the world to produce a lot more food because a chicken, for instance, must eat two calories worth of grain to produce one calorie of poultry for human consumption, and a chicken is one of the better converters of calories. A pig eats three times as many calories as it produces, and a cow needs to eat six calories for every calorie of beef.
In other words, as population increases and developing nations begin to eat more of the American diet, we’ll need to produce a lot more grain, up to six times as much grain, says Gates. That will increase global emissions from the agriculture sector when the goal is net-zero emissions.
Plant-based “meat” is one potential solution, and Gates is an investor in two companies that are developing plant-based meat alternatives—Beyond Meat and Impossible Foods. The cost, or “green premium,” of plant-based “meat” products is still significantly higher than the real thing, and while the taste and texture is getting better, it’s going to be difficult to convince meat-eaters to go vegan.
The other big contributor to climate change on the farm comes from fertilizers. Plants need nitrogen to grow, and they’ll keep growing as long as they get plenty of it. Plants get nitrogen in nature from ammonia that is produced by microbes in the soil. As Gates points out, making ammonia takes a lot of energy for these little micro-organisms, so they only make it when it’s needed. Dump tons of nitrogen on the soil and the microbes don’t make any at all— because they don’t need to. It disrupts the natural cycle.
But the problem comes from dumping too much fertilizer on the land. It runs into creeks and streams, causing pollution, and escapes into the air in the form of nitrous oxide (again, having 265 times the climate-warming effect of carbon dioxide.) As much as half of the nitrogen is wasted from over-application, says Gates. And making the stuff and transporting it adds further to the climate effects of fertilizer.
Gates also discusses food waste (in the US, as much as 40 percent of our food is wasted) and deforestation (such as the clearing of the Amazon rainforest for more cow pastures). But I wish he had discussed regenerative agriculture practices in greater detail, including organic and no-till methods of farming. Cover crops and crop rotation are also key in the battle for climate. Many scientists believe that sustainable farming practices can be our most cost-effective way to pull carbon from the atmosphere.
Farmer Bill now happens to be the largest private owner of farmland in the world. Gates and his investment companies have been quietly buying up farmland across the United States. He doesn’t really say why in his book, but it makes me wonder what else he knows.
Robert Turner is the director of the Creekside Farm Education Center and the author of Carrots Don’t Grow on Trees: Building Sustainable and Resilient Communities. To learn more, visit EatYourView.com.
