Additional efforts are required to mitigate climate change under rapid demographic transitions

Facing the challenge of integrating demographic transitions with climate change mitigation, a recent Cell Reports Sustainability article investigates Japan's aging society and its impact on carbon emissions. Here, we emphasize the need for policies tailored to demographic nuances to effectively promote green technology adoption and achieve a sustainable future. Facing the challenge of integrating demographic transitions with climate change mitigation, a recent Cell Reports Sustainability article investigates Japan's aging society and its impact on carbon emissions. Here, we emphasize the need for policies tailored to demographic nuances to effectively promote green technology adoption and achieve a sustainable future. Countries across the globe are witnessing a significant shift in the age demographics of their populations, predominantly driven by advancements in health care and a decline in fertility rates. According to the United Nations, the global landscape is set to transform dramatically by 2050, with one in six people worldwide projected to be over the age of 65, marking a significant increase from one in eleven in 2019.1United Nations, Department of Economic and Social Affairs, Population DivisionWorld Population Ageing 2019 (ST/ESA/SER.A/444).2020https://www.un.org/en/development/desa/population/publications/pdf/ageing/WorldPopulationAgeing2019-Highlights.pdfCrossref Google Scholar This swift acceleration in the aging of populations worldwide poses challenges to societal infrastructure and economic sustainability. Specifically, it is anticipated to lead to a notable contraction in the labor market, impose increased burdens on public health systems, and trigger a surge in pension demands.2Harper S. Economic and social implications of aging societies.Science. 2014; 346: 587-591https://doi.org/10.1126/science.1254405Crossref PubMed Scopus (383) Google Scholar,3Luo Y. Su B. Zheng X. Trends and Challenges for Population and Health During Population Aging — China, 2015–2050.China CDC Wkly. 2021; 3: 593-598https://doi.org/10.46234/ccdcw2021.158Crossref PubMed Scopus (76) Google Scholar These shifts are poised to not only hamper economic growth but also potentially reshape patterns of energy consumption and carbon emissions, thereby exerting a profound influence on the dynamics of climate change.4Hugo G. Future demographic change and its interactions with migration and climate change.Glob. Environ. Change. 2011; 21: 21-33https://doi.org/10.1016/j.gloenvcha.2011.09.008Crossref Scopus (170) Google Scholar,5Jones B. Tebaldi C. O'Neill B.C. Oleson K. Gao J. Avoiding population exposure to heat-related extremes: demographic change vs climate change.Clim. Change. 2018; 146: 423-437https://doi.org/10.1007/s10584-017-2133-7Crossref Scopus (77) Google Scholar,6Zheng H. Long Y. Wood R. Moran D. Zhang Z. Meng J. Feng K. Hertwich E. Guan D. Ageing society in developed countries challenges carbon mitigation.Nat. Clim. Chang. 2022; 12: 241-248https://doi.org/10.1038/s41558-022-01302-yCrossref Scopus (40) Google Scholar For example, an aging society may rely more on delivery services, and this might in turn indirectly contribute to increased emissions. Governments and non-governmental organizations (NGOs) globally are actively implementing measures to adapt to these demographic changes and mitigate their impacts on climate change. Technology innovation has been widely proposed as an effective way to reduce carbon emissions and meet aging populations' diverse needs. However, the adoption of such new technologies largely depends on the extent to which the elderly find those technologies acceptable.7Allan J.I. Hadden J. Exploring the framing power of NGOs in global climate politics.Env. Polit. 2017; 26: 600-620https://doi.org/10.1080/09644016.2017.1319017Crossref Scopus (86) Google Scholar,8United Nations Framework Convention on Climate ChangeAdoption of the Paris Agreement: Draft Decision.2015https://documents.un.org/symbol-explorer?s=FCCC/CP/2015/L.9/REV.1&i=FCCC/CP/2015/L.9/REV.1_0743552Google Scholar For example, their adoption hinges on factors including but not limited to ease of use, relevance to the aging population, and availability of supportive infrastructure to facilitate their integration into daily life. This suggests that technology innovations targeting mitigating climate change, particularly in an aging society, not only need to consider broader climate change mitigation goals but also need to accommodate the diverse needs of an aging population and associated household size change to reach their full potential. In the context of global demographic change and its implications for climate change, a recent Cell Reports Sustainability article by Long et al.9Long Y. Yoshida Y. Huang L. Chen P. Wu Y. Gasparatos A. Demographic transitions hinder climate change mitigation for Japan's shrinking and aging households.Cell Rep. Sustain. 2024; 1100056https://doi.org/10.1016/j.crsus.2024.100053Abstract Full Text Full Text PDF Google Scholar examines how demographic transitions impact household sector emissions, with a focus on Japan—a nation distinguished by the high proportion of elderly people in its population. The study employs a robust household classification system, segmenting 9,996 Japanese households into six distinct categories based on comprehensive dimensions: income level, household size, average age, driving demand, and presence of children. This analysis underscores disparities in energy consumption and carbon emissions across various household demographics, incorporating their propensity for adopting decarbonization technologies, including roof solar photovoltaics (PVs) and new energy vehicles (NEVs). The findings reveal that smaller-size and elderly households may inadvertently pose challenges to emission reduction initiatives, which is attributed to the use of less efficient household devices and a diminished receptivity toward novel low-carbon technologies. Despite the potential of green technologies for mitigating emissions, their uptake is markedly influenced by household income and lifestyle. While affluent families exhibit a higher adoption rate of PV technology, driven by financial capacity and environmental consciousness, adoption rates are lower in low-income and elderly households, hindered by financial limitations and technology acceptance barriers. Similarly, NEVs are predominantly adopted by high-income households capable of affording the associated costs, yet their impact on emission reduction is constrained by those households' ownership of multiple vehicles. Japan's leadership, in addressing the challenges of an aging society, offers valuable insights for the global community. Long et al.'s recommendations for establishing policies targeting low-income and elderly households can incentivize greater adoption of energy-saving and environmentally friendly measures, presenting practical solutions for addressing these challenges worldwide. These research findings are not limited to Japan but are meaningful to other aging nations, like Italy and Germany, where similar demographic shifts are occurring.10Berkeley N. Bailey D. Jones A. Jarvis D. Assessing the transition towards Battery Electric Vehicles: A Multi-Level Perspective on drivers of, and barriers to, take up.Transp. Res. Part A Policy Pract. 2017; 106: 320-332https://doi.org/10.1016/j.tra.2017.10.004Crossref Scopus (105) Google Scholar Elderly individuals in these societies may also show lower acceptance of emerging low-carbon technologies. In addition, income levels may be likely to play a similar role in other countries when considering the adoption of low-carbon technologies among elder households because households' financial capacities in general influence people's available budgets for investing in the initial costs associated with green technologies such as solar panels. However, it is critical to recognize the contextual differences that may influence the generalizability of Long et al.'s findings to other countries. Specifically, the unique socioeconomic conditions, cultural norms, governmental policies, and infrastructure development levels play crucial roles in the adoption of technological innovations within an aging society. For instance, Italy's historic reliance on fossil fuels for energy might impact the feasibility and acceptance of renewable-energy-based solutions in households. On the other hand, Germany's proactive stance on renewable energy, through supportive policies and investments, could create a more favorable context for elder households to adopt green technologies. These examples underscore the necessity of examining each country's distinct context to accurately assess the potential for technology adoption among its aging population. This necessitates additional investigation into whether other countries will follow Japan's trend toward smaller household sizes. Notably, smaller households often have higher per capita carbon emissions due to their greater per capita energy consumption. In particular, when all other factors are held constant, households with fewer members tend to have higher per capita energy consumption and carbon emissions related to heating. To tackle the dual challenges of demographic change and climate change, innovative solutions integrating technology and policy adjustments are essential. Additional efforts, such as promoting technologies and sustainable urban planning suitable for the elderly and encouraging green technology adoption across all age groups, are crucial. In this respect, promoting old-house renovation and heating electrification may be good options that could achieve dual benefits for climate and health in consideration of the lifestyles of the elderly. We must proactively prepare for global aging by reforming economic and social infrastructure while also seizing the opportunities for industrial transformation brought about by demographic shifts. The transition toward an aging society has the potential to become a new growth point for the "silver economy" if population aging is viewed as an opportunity to drive economic development and technological innovation rather than merely a challenge. The author is a member of Cell Reports Sustainability's scientific advisory board. Demographic transitions hinder climate change mitigation for Japan's shrinking and aging householdsLong et al.Cell Reports SustainabilityMarch 12, 2024In BriefIn their study, Long et al. analyze Japanese household energy consumption and emissions. The research finds people's age, household size, and income to be associated with emissions and the adoption of green technologies such as photovoltaics and new energy vehicles. It shows that demographic transitions associated with household aging and shrinking can have significant ramifications on climate change mitigation efforts in the household sector. Full-Text PDF Open Access