Feeding people in major cities exerts a lot more pressure on the environment than you might think. Take the nine-county San Francisco Bay Area, for example, which has a total population of some 7 million people. Feeding that many people means importing 2.5 to 3 million tons of food per day over an average distance of 500 to 1,000 miles, which requires massive amounts of energy and generates significant greenhouse gas emissions. And even with all that food coming in, 1 out of every 8 people in the region have little access to food. With that being said, there is a way to alleviate some of this food insecurity while minimizing emissions: Urban agriculture. In Cuba, more than 300,000 urban farms and gardens produce about 50 percents of the island’s fresh produce, reaching yields of 44 pounds of food per square meter per year. If trained farmers in Oakland could achieve just half of Cuban yields, 1,200 acres of land would be enough to provide 100 kilograms of food per year per person to more than 90 percent of Oakland residents. This would drastically limit the need for transporting food over long distances and provide people with locally grown food, all while sucking carbon out of the air by adding more green space across the city. If we want to improve food security in American cities, we must continue focusing on urban farming.