Abstract
Policies and strategies to improve environmental sustainability in cities and regions have often focused on a single sector, subsystem or impact category, or a small number of them, limiting their potential to effectively reduce overall environmental impacts. Comprehensive frameworks are needed to adequately assess environmental impacts and to identify hotspots, trade-offs and opportunities with substantial improvement potential. This article introduces a systematic framework to calculate the potential life-cycle environmental impacts of consumption at the regional and city levels. The framework is applied to the Autonomous Province of Trento and its capital city, Trento, in northern Italy. The framework draws on (i) a state-of-the-art methodology combining urban metabolism and life-cycle assessment, which estimates cradle-to-gate environmental impacts of urban consumption, and (ii) the EU Consumption Footprint methodology, which estimates cradle-to-grave environmental impacts of household consumption. First, we develop a material flow accounting model to estimate annual consumption of thousands of product types. Second, we select a set of representative product types based on their relative mass consumption shares and on their potential environmental impacts, as identified in existing research, to ensure relevant coverage across all consumption areas. Third, we develop a cradle-to-grave life-cycle model to assess the potential environmental impacts of consumption across a broad range of impact categories. Cradle-to-grave and cradle-to-gate results are compared, highlighting the importance of a cradle-to-grave perspective, including food, buildings and transport, which contribute significantly to the overall impacts associated with regional and urban areas. This comprehensive and systematic framework can support more effective and integrated decision-making by comprehensively addressing consumption-driven environmental impacts of cities and regions across the full life cycle.