Examining household carbon emissions through a supply chain perspective reveals the climate impact of consumption behaviors and variations across societal structures and features. Despite the evident and expanding environmental inequality, strategies for its mitigation and prioritization remain debated. This study investigates the origins of carbon emission inequalities from household consumption, using Japan as a case study, a society characterized by aging demographics and comparatively equal income redistribution. By quantitatively analyzing household carbon footprints, we observe a U-shaped distribution in emissions as income levels increase. Notably, the carbon footprint sizes are strikingly similar between the lowest and highest income groups, yet inequalities emerge in education and investments in future generations. Integrating these findings, this study further conducts a scenario analysis to project shifts in future low-carbon lifestyles, indicating that middle-income groups are more prone to achieving personal-level decarbonization. This projection is vital in understanding how to effectively address carbon footprint inequalities, especially considering the entrenched preferences in wealthier demographics for investing in future generations.

中文翻译：

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考虑到家庭时间使用模式，碳足迹不平等扩大

从供应链的角度审视家庭碳排放，揭示了消费行为以及社会结构和特征的变化对气候的影响。尽管环境不平等现象明显且不断扩大，但缓解和优先考虑的策略仍然存在争议。本研究以日本为案例研究，调查了家庭消费中碳排放不平等的根源，日本是一个人口老龄化和收入再分配相对平等的社会。通过定量分析家庭碳足迹，我们观察到随着收入水平的增加排放量呈 U 形分布。值得注意的是，最低收入群体和最高收入群体的碳足迹大小惊人相似，但后代的教育和投资却出现了不平等。综合这些发现，本研究进一步进行了情景分析，以预测未来低碳生活方式的转变，表明中等收入群体更容易实现个人层面的脱碳。这一预测对于理解如何有效解决碳足迹不平等问题至关重要，特别是考虑到富裕人群对投资子孙后代的根深蒂固的偏好。