Raising the roof: Why some Israeli farmers are looking up
As more open fields are zoned for construction, where will our food be grown? City rooftops may provide the answer.
Cities are deserts when it comes to producing food, but city dwellers comprise more than 50 percent of the world’s population. They will constitute 80 percent of it in 2050, when cities will occupy 70 percent of all the populated areas on Earth. And by the middle of this century, the human population will amount to 9 billion.