This paper presents an approach for assessing lifestyle carbon footprints and lifestyle change options aimed at achieving the 1.5 °C climate goal and facilitating the transition to decarbonized lifestyles through stakeholder participatory research. Using data on Finland and Japan it shows potential impacts of reducing carbon footprints through changes in lifestyles for around 30 options covering food, housing, and mobility domains, in comparison with the 2030 and 2050 per-capita targets (2.5–3.2 tCO₂e by 2030; 0.7–1.4 tCO₂e by 2050). It discusses research opportunities for expanding the footprint-based quantitative analysis to incorporate subnational analysis, living lab, and scenario development aiming at advancing sustainability science on the transition to decarbonized lifestyles.

Cities and urban consumers play a central role in the transition to a decarbonized society. Building on existing studies that identify the significant contributions of lifestyle changes, this study proposes a practical methodology for modeling and exploring city-specific carbon footprint reduction pathways through lifestyle changes to decarbonization. It uses an input–output approach with mixed-unit consumption data and the concept of adoption rates, which is applicable to multiple cities with widely available subnational household consumption data. This paper illustrates the use of this methodology by exploring the consumption-based mitigation pathways of 52 Japanese cities with 65 lifestyle change options covering mobility, housing, food, consumer goods, and leisure domains. The results revealed that city-specific impacts of a variety of lifestyle change options can differ by as much as a factor of five among cities, even in the urban context within the same country. Due to this city-level heterogeneity, the priority options of decarbonized lifestyles, such as among shared mobility, low-carbon diets, and longevity of consumer goods, have shifted between cities. The analysis suggests that ambitious urban lifestyle changes can potentially reduce their carbon footprints to meet the 1.5 °C target. However, due to the overlaps of mitigation potentials between multiple lifestyle change options, the necessary levels of adoption and coverage are extensive (i.e. adoption rates of 0.6–0.9). Importantly, adopting lifestyle changes with an efficiency strategy (e.g. the introduction of end-use technologies) or sufficiency strategy (e.g. behavioral changes in consumption amounts and modes) alone is not enough; the only way to succeed is through the combination of both strategies. This paper calls for a target-based exploration and identification of city-specific priorities of lifestyle change options to facilitate consumption-oriented mitigation policies and stakeholder actions to address the climate impacts of urban consumption.

Addressing the prevailing mode of high-carbon lifestyles is crucial for the transition towards a net-zero carbon society. Existing studies fail to fully investigate the underlining factors of unsustainable lifestyles beyond individual determinants nor consider the gaps between current footprints and reduction targets. This study examines latent lifestyle factors related to carbon footprints and analyzes gaps between decarbonization targets and current lifestyles of major consumer segments through exploratory factor analysis and cluster analysis. As a case study on Japanese households, it estimates carbon footprints of over 47,000 households using expenditure survey microdata, and identifies high-carbon lifestyle factors and consumer segments by multivariate regression analysis, factor analysis, and cluster analysis. Income, savings, family composition, house size and type, ownership of durables and automobiles, and work style were confirmed as determinants of high-footprint Japanese households, with eight lifestyles factors, including long-distance leisure, materialistic consumption, and meat-rich diets, identified as the main contributory factors. The study revealed a five-fold difference between lowest and highest footprint segments, with all segments overshooting the 2030 and 2050 decarbonization targets. The findings imply the urgent need for policies tailored to diverse consumer segments and to address the underlying causes of high-carbon lifestyles especially of high-carbon segments.

Sustainable Consumption and Production (SCP) was adopted as a stand-alone goal and reflected as one of the cross-cutting objectives of the Sustainable Development Goals (SDGs), with a central role to address global resource consumption and its associated environmental impacts, as well as numerous social and economic issues. With this broad characterization of SCP, policy integration is crucial in addressing it at national level. This paper analyzes characteristics of SCP policy integration based on a survey of national government policies. It reveals that SCP is not fully integrated in national policy-making; high resource consumption sectors such as urban planning, building, and tourism are not fully incorporated into national SCP policies, and there is only limited participation of relevant government ministries other than environment ministries. We find that among countries with horizontal policy integration, those with Green Economy/Green Growth frameworks tend to have better sectoral integration; and those with SCP-specific frameworks are likely to have broader coordination of ministries. By conducting cross-analysis using income level and region, the different characteristics of SCP policy-making approaches were identified. The results of this study provide a better understanding of how SCP is integrated into policy for effective national policy-making and measurement of the SDG Goal 12.