A swath of Amazon rainforest in Mato Grosso state, Brazil, goes up in smoke to create new fields for corn and soybeans. Brazil has converted a fifth of the Amazon rainforest within its borders to farmland over the last fifty years, an area of almost 300,000 square miles. Such land-use change from forest to field emits copious amounts of carbon dioxide and is one reason global agriculture contributes nearly a third of all human-caused greenhouse gas emissions each year. Scientists estimate that the world will need to produce nearly 60 percent more food by 2050 to feed a projected global population of around ten billion people. But we must do that without cutting down more carbon-sequestering forests. We already use half of Earth’s vegetated land for agriculture, and without increasing yields or changing diets, another 2.3 million square miles of forests could fall by 2050, threatening not only wildlife, but also a stable climate conducive to growing crops.
