In light of societal shifts such as an aging population, delayed marriages, and higher rates of divorce, there's a notable rise in solitary living, affecting society, the economy, and the environment. To understand the implications of these demographic shifts, our research examines the nexus between solo living and its broader social-environmental consequences. Using Japan, one of the countries with the highest proportion of the elderly, as a reference, we explore the temporal fluctuations, gender-specific variances, and long-term trends in carbon footprints influenced by alterations in consumption behaviors. Results indicate that housing energy and food consumption remain the dominant carbon footprint contributors across all demographic sectors. Interestingly, single households present higher carbon footprints than non-single households, with those of single females surpassing their male counterparts due to increased household energy use and expenditures on clothing and healthcare. Following the demographic shifts, single households are expected to account for approximately 31.1% of Japan's emissions from households by 2040, challenging national decarbonization efforts due to their higher per capita emissions. This highlights the imperative for bespoke strategies, especially in resource allocation and sharing, to address the solo living challenge and ensure congruence with Japan's sustainability and decarbonization goals.

中文翻译：

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越来越多的单身家庭挑战日本家庭脱碳

鉴于人口老龄化、晚婚和离婚率上升等社会变化，独居生活显着增加，影响着社会、经济和环境。为了了解这些人口变化的影响，我们的研究考察了独居与其更广泛的社会环境后果之间的联系。以老年人口比例最高的国家之一日本为参考，我们探讨了消费行为变化影响的碳足迹的时间波动、性别差异和长期趋势。结果表明，住房能源和食品消费仍然是所有人口部门的主要碳足迹贡献者。有趣的是，单身家庭的碳足迹高于非单身家庭，其中单身女性由于家庭能源消耗以及服装和医疗保健支出的增加而超过了男性。随着人口结构的变化，预计到 2040 年，单一家庭的排放量将占日本家庭排放量的约 31.1%，由于其人均排放量较高，这对国家脱碳工作构成了挑战。这凸显了制定战略的必要性，特别是在资源分配和共享方面，以应对单独生活的挑战并确保与日本的可持续发展和脱碳目标保持一致。