Carbon Footprint Differentiation in the Japanese Residential Sector Due To Income‐Driven Divergences in Consumption and Time Allocation.

Households are responsible for a large fraction of the direct and indirect emissions of greenhouse gases (GHG) at the national level. However, emission patterns are not homogeneous within the residential sector, with several factors affecting them. This study explores how income‐related divergences in consumption and time allocation affect the carbon footprint of the Japanese residential sector. To achieve this, we combine data on emission intensities from national input‐output tables with household‐level consumption and time allocation data from two large‐scale nationally representative surveys. Overall, we find that indirect emissions account for approximately 78% of the overall carbon footprint of the residential sector across the studied income groups. The overall carbon footprint and the emissions of several individual consumption categories follow an N‐shaped curve, with some of the lower‐income groups having disproportionately higher emissions compared to middle‐ and higher‐income groups. Conversely, emissions for other individual consumption categories increase almost linearly with income. This points to the fact that different factors can affect emissions across income groups. Specifically, the N‐shaped curves are driven by the propensity of lower‐income households to spend more time at home and rely on inefficient technologies, while the linear trend is driven by the propensity of higher‐income households to consume more. A detailed understanding of how these factors affect emissions patterns can provide useful insights for designing and implementing effective policies to achieve decarbonization the residential sector. Plain Language Summary: Income‐driven divergences in consumption and lifestyles affect the carbon footprint of households. Thus, it is important to consider how household demographic and socioeconomic characteristics and lifestyles affect emissions when designing effective and equitable emission reduction strategies to achieve decarbonization. The detailed understanding of the impact of these factors on emission patterns provides useful insights for designing and implementing effective policies to achieve decarbonization in the residential sector. In this study, emissions intensity from national input‐output tables, household consumption and time allocation data from two nationally representative large‐scale surveys are used. According to our study, the overall carbon footprint and emissions of several consumption categories follow an N‐shaped curve (e.g., eating at home, energy supply and sewage), indicating that some other low‐income groups have disproportionately higher emissions compared to middle‐ and high‐income groups. In contrast, emissions from other consumption categories increase almost linearly with income (e.g., eating out of home, transport and communication, entertainment and education). The tendency of low‐income households to spend more time at home and rely on inefficient technologies drives the N‐shaped curve, while the tendency of higher emissions in high‐income households are driven by their greater consumption. Key Points: The overall household carbon footprint follows an N‐shaped curve with incomeEmissions differentiation due to income‐driven consumption and time allocation divergencesDisproportionately high emissions from in‐home activities for low‐income households [ABSTRACT FROM AUTHOR]