Read this recent essay by Dr. Dickson Despommier on the benefits of vertical farming:
The advent of agriculture has ushered in an unprecedented increase in the human population and their domesticated animals. Farming catalyzed our transformation from primitive hunter-gatherers to sophisticated urban dwellers in just 10,000 years. Today, over 800 million hectares is committed to soil-based agriculture, or about 38% of the total landmass of the earth. It has re-arranged the landscape in favor of cultivated fields at the expense of natural ecosystems, reducing most natural areas to fragmented, semi-functional units, while completely eliminating many others. A reliable food supply was the result. This singular invention has facilitated our growth as a species to the point now of world domination over the natural world from which we evolved. Despite the obvious advantage of not having to hunt or scavenge for our next meal, farming has led to new health hazards by creating ecotones between the natural world and our cultivated fields. As the result, transmission rates of numerous infectious disease agents have dramatically increased- influenza, rabies, yellow fever, dengue fever, malaria, trypanosomiasis, hookworm, schistosomiasis – and today these agents emerge and re-emerge with devastating regularity at the tropical and sub-tropical agricultural interface. Modern agriculture employs a multitude of chemical products, and exposure to toxic levels of some classes of agrochemicals (pesticides, fungicides) have created other significant health risks that are only now being sorted out by epidemiologists and toxicologists. As if that were no enough to be concerned about, it is predicted that over the next 50 years, the human population is expected to rise to at least 8.6 billion, requiring an additional 109 hectares to feed them using current technologies, or roughly the size of Brazil. That quantity of additional arable land is simply not available. Without an alternative strategy for dealing with just this one problem, social chaos will surely replace orderly behavior in most over-crowded countries. Novel ways for obtaining an abundant and varied food supply without encroachment into the few remaining functional ecosystems must be seriously entertained. One solution involves the construction of urban food production centers – vertical farms – in which our food would be continuously grown inside of tall buildings within the built environment. If we could engineer this approach to food production, then no crops would ever fail due to severe weather events (floods, droughts, hurricanes, etc.). Produce would be available to city dwellers without the need to transport it thousands of miles from rural farms to city markets. Spoilage would be greatly reduced, since crops would be sold and consumed within moments after harvesting. If vertical farming in urban centers becomes the norm, then one anticipated long-term benefit would be the gradual repair of many of the world’s damaged ecosystems through the systematic abandonment of farmland. In temperate and tropical zones, the re-growth of hardwood forests could play a significant role in carbon sequestration and may help reverse current trends in global climate change. Other benefits of vertical farming include the creation of a sustainable urban environment that encourages good health for all who choose to live there; new employment opportunities, fewer abandoned lots and buildings, cleaner air, safe use of municipal liquid waste, and an abundant supply of safe drinking water.