Urban agriculture’s bounty: contributions to Phoenix’s sustainability goals

With over half of the world's population living in cities, there is mounting evidence indicating that investments in urban sustainability can deliver high returns on socioeconomic and environmental fronts. Current scholarship on urban agriculture (UA) reports a wide range of benefits which have been shown to vary with the scale and type of benefit examined. Notably, most city-scale studies do not align benefits of UA with locally meaningful goals. We fill this gap by conducting a city-scale analysis for Phoenix, the fifth largest city in the USA by population, and evaluate these benefits based on their ability to contribute to select desired outcomes specified in Phoenix's 2050 Sustainability Goals: the elimination of food deserts, provision of green open space, and energy and CO2 emissions savings from buildings. We consider three types of surfaces for UA deployment-undeveloped vacant lots, flat rooftops, and building facades-and find that the existing building stock provides 71% of available UA space in the study area. The estimated total food supply from UA is 183 000 tons per year, providing local produce in all existing food deserts of Phoenix, and meeting 90% of current annual consumption of fresh produce based on national per capita consumption patterns. UA would also add green open space and reduce by 60% the number of block groups underserved by public parks. Rooftop deployment of UA could reduce energy use in buildings and has the potential to displace more than 50 000 tons of CO2 per year. Our work highlights the importance of combining a data-driven framework with local information to address place-based sustainability goals and can be used as a template for city-scale evaluations of UA in alternate settings.