This paper develops a generalizable systems framework to analyze the food-energy-water (FEW) nexus from an urban systems perspective, connecting in-and trans-boundary interactions, quantifying multiple environmental impacts of community-wide FEW provisioning to cities, and visualizing FEW supply-chain risks posed to cities by the environment. Delhi's community-wide food demand includes household consumption by socio-economic-strata, visitors-and industrial food-use. This demand depends 90%, 76%, and 86% on trans-boundary supply of FEW, respectively. Supply chain data reveal unique features of trans-boundary FEW production regions (e.g. irrigation-electricity needs and GHG intensities of power-plants), yielding supply chaininformed coupled energy-water-GHG footprints of FEW provisioning to Delhi. Agri-food supply contributes to both GHG (19%) and water-footprints (72%-82%) of Delhi's FEW provisioning, with milk, rice and wheat dominating these footprints. Analysis of FEW interactions within Delhi found >75% in-boundary water-use for food is for urban agriculture and >76% in-boundary energy-use for food is from cooking fuels. Food waste-to-energy and energy-intensity of commercial and industrial food preparation are key data gaps. Visualizing supply chains shows >75% of water embodied in Delhi's FEW supply is extracted from locations over-drafting ground water. These baseline data enable evaluation of future urban FEW scenarios, comparing impacts of demand shifts, production shifts, and emerging technologies and policies, within and outside of cities.

This paper develops a methodology for individual cities to use to analyze the in- and trans-boundary water, greenhouse gas (GHG), and land impacts of city-scale food system actions. Applied to Delhi, India, the analysis demonstrates that city-scale action can rival typical food policy interventions that occur at larger scales, although no single city-scale action can rival in all three environmental impacts. In particular, improved food-waste management within the city (7% system-wide GHG reduction) matches the GHG impact of preconsumer trans-boundary food waste reduction. The systems approach is particularly useful in illustrating key trade-offs and co-benefits. For instance, multiple diet shifts that can reduce GHG emissions have trade-offs that increase water and land impacts. Vertical farming technology (VFT) with current applications for fruits and vegetables can provide modest system-wide water (4%) and land reductions (3%), although implementation within the city itself may raise questions of constraints in water-stressed cities, with such a shift in Delhi increasing community-wide direct water use by 16%. Improving the nutrition status for the bottom 50% of the population to the median diet is accompanied by proportionally smaller increases of water, GHG, and land impacts (4%, 9%, and 8%, systemwide): increases that can be offset through simultaneous city-scale actions, e.g., improved food-waste management and VFT.

Food action plans in many global cities articulate interest in multiple objectives including reducing in-and trans-boundary environmental impacts (water, land, greenhouse gas (GHG)). However, there exist few standardized analytical tools to compare food system characteristics and actions across cities and countries to assess trade-offs between multiple objectives (i.e., health, equity) with environmental outcomes. This paper demonstrates a streamlined model applied for analysis of four cities with varying characteristics across the United States and India, to quantify system-wide water, energy/GHG, and land impacts associated with multiple food system actions to address health, equity, and environment. Baseline diet analysis finds key differences between countries in terms of meat consumption (Delhi 4; Pondicherry 16; United States 59, kg/capita/year), and environmental impact of processing of the average diet (21%, 19%, <1%, <1% of community-wide GHG-emissions for New York, Minneapolis, Delhi, and Pondicherry). Analysis of supply chains finds city average distance (food-miles) varies (Delhi 420; Pondicherry 200; United States average 1,640 km/t-food) and the sensitivity of GHG emissions of food demand to spatial variability of energy intensity of irrigation is greater in Indian than US cities. Analysis also finds greater pre-consumer waste in India versus larger post-consumer accumulations in the United States. Despite these differences in food system characteristics, food waste management and diet change consistently emerge as key strategies. Among diet scenarios, all vegetarian diets are not found equal in terms of environmental benefit, with the US Government's recommended vegetarian diet resulting in less benefit than other more focused targeted diet changes. K E Y W O R D S environmental footprinting, food action planning, food-energy-water nexus, industrial ecology, sustainable urban systems, urban food systems 1 INTRODUCTION In recent years, cities have begun giving greater attention to the food systems supporting their city populations and economies (i.e., Milan Urban Food Policy Pact, 2015). Many cities are developing food action plans, with multiple objectives related to health and nutrition, environmental sustainability, equity, and economy. Multiple international organizations, such as the Milan Urban Food Pact, and Food and Agriculture Organization's (FAO's) Food for the Cities are currently working to help cities create changes in their food system related to these multiple sustainability outcomes. Many of these urban food actions align with United Nations Sustainable Development Goals (SDGs) related to the food system, including "Zero hunger" (Goal 2), "Good health and well-being" (Goal 3), "Decent work and economic growth" (Goal 8), "Reduce inequalities" (Goal 10), and multiple environmental goals (Goals 11-15), for example. However, for a city to take action in their food system to achieve these multiple sustainability outcomes, this requires first an understanding of the structure and character...

With ever-growing populations, cities are increasingly interested in ensuring a well-functioning food system. However, knowledge of variation between individual city food systems is limited. This is particularly true in countries such as India, experiencing significant issues related to food security and sustainability. This paper advances the understanding of urban food systems, by analyzing the unique food systems of nine cities within India, through the integration of multiple city-specific data sources including demand of residents, visitors and industries, and commodity-specific supply chains to assess nutrition, environmental impact, and supply risk. This work finds a large degree of intercity food system variability across multiple food system characteristics. Specifically, levels of undernutrition vary, with the percentage of city populations who are underconsuming protein ranging from 0% to 70%, and for calories 0% to 90%. Environmental impacts (consumptive water loss, land use, and greenhouse gas emissions) of urban food demand also show variation, largely influenced by differing composition of residential diet. Greenhouse gas emissions are also largely influenced by location of production and spatially informed energy intensity of irrigation. Supply chain distance ("food-miles") also vary by city, with the range of 196 (Pondicherry) to 1,137 (Chennai) km/Mg-shorter than more industrialized nations such as the United States. Evaluating supply chain risk in terms of water scarcity in food-producing regions that serve city demand finds production locations, on average, to be less water-scarce than the watersheds local to the urban environments. This suggests water-intensive agriculture may at times be best located at a distance from urban centers and competing demands.

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