Assessing the impacts of fertility and retirement policies on China’s carbon emissions

nature climate change Article https://doi.org/10.1038/s41558-024-02162-4 Assessing the impacts of fertility and retirement policies on China’s carbon emissions Received: 2 August 2022 Accepted: 18 September 2024 Ling Tang 1, Junai Yang 2, Jiali Zheng 3, Xinlu Sun 4, Lu Cheng5, Kehan He 6, Ling Li 7, Jinkai Li 8 , Wenjia Cai 9, Shouyang Wang Paul Drummond 11 & Zhifu Mi 4 , 1,2,10 Published online: xx xx xxxx Check for updates The gradual adjustment of fertility and retirement policies in China has social benefits in terms of coping with population aging. However, the environmental consequences of these policies remain ambiguous. Here we compile environmentally extended multiregional input–output tables to estimate household carbon footprints for different population age groups in China. Subsequently, we estimate the age-sex-specific population under different fertility policies up to 2060 and assess the impacts of fertility and retirement policies on household carbon footprints. We find that Chinese young people have relatively higher household carbon footprints than their older counterparts due to differences in income by age group. Relaxing fertility policies and delaying retirement age are associated with an increase in population (and labour supply) and thus increases in household carbon footprints, with the majority of these increases from the fertility side. These results may help policymakers understand interactions among those measures targeting population aging and climate action. Mitigating climate change and coping with population aging are both critical goals for China in achieving sustainable development1,2. As the world’s largest carbon emitter, China aims to have a carbon emissions peak before 2030 and achieve carbon neutrality by 20603. Currently, China is turning towards more sustainable development, with the deceleration of China’s annual carbon emissions growth from 10% (2000–2010) to 2% (2010–2020)4. However, China remains an important driver of global carbon emissions due to its large population and growing household consumption over the past 20 years. To better explore the drivers of carbon emissions, the household carbon footprint (the sum of direct and indirect carbon emissions of household consumption along the supply chain) has received increasing attention recently1,5,6. In addition, China is one of the most populous countries in the world, with a population that is nearing its peak and aging rapidly7. In 2020, China’s total fertility rate was only 1.3 births per woman, which is far below the replacement level (2.1) needed for a stable population8. It is projected that China’s population will peak at 1.45 billion in 2029 (with a range of 1.42 to 1.48 billion from 2025 to 2035)2,9, after which contraction is expected. At the same time, China is aging rapidly, with the proportion aged 65 years and above doubling from 7% in 2000 to 14% in 202010. China has implemented a national strategy to address population aging, including relaxing fertility policies and delaying retirement age. In the 1970s, a one-child policy was introduced to curb School of Economics and Management, University of Chinese Academy of Sciences, Beijing, China. 2Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing, China. 3The School of Management, Xi’an Jiaotong University, Xi’an, China. 4The Bartlett School of Sustainable Construction, University College London, London, UK. 5School of Ecology and Environment, Renmin University of China, Beijing, China. 6Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong SAR, China. 7International School of Economics and Management, Capital University of Economics and Business, Beijing, China. 8School of Economics, Beijing Institute of Technology, Beijing, China. 9Department of Earth System Science, Tsinghua University, Beijing, China. 10School of Entrepreneurship and Management, ShanghaiTech University, Shanghai, China. 11Institute for Sustainable Resources, University College London, London, UK. e-mail: ; 1 Nature Climate Change Article population growth and alleviate severe poverty in China2. Following the introduction of this policy, the fertility rate decreased—the total fertility rate declined sharply from approximately 5.8 in 1970 to 2.8 in 1979 and was thought to be approximately 1.6 in 2010—resulting in a rapidly aging population7,11. In October 2015, China’s one-child policy was replaced with a two-child policy to counter this trend12. The two-child policy has had a positive effect on the birth rate: more than 10 million babies were born as a second child in China during 2013–2017, and the proportion of newborns who were second children in new births increased from 30% in 2013 to 50% in 20178. However, a continuous fall in the number of women of childbearing age and a gradual decline in the effect of the two-child policy resulted in a drop in the number of new births during the period 2017–20208. In May 2021, in an attempt to tackle demographic challenges, China further relaxed its fertility policy with a three-child policy, allowing all couples to have up to three children 13. In addition, many supportive measures have been implemented to address housing and educational costs, aiming to ease the financial burden of raising children14. However, the retirement age in China, 60 years for men and an average of 52.5 years for women (50 years for women workers and 55 years for women cadres)2, is among the lowest in the world: the official retirement age for most developed countries is 65 years or even higher15,16. According to the Outline of the 14th Five-Year Plan (2021–2025), China called for the extension of the statutory retirement age in a gradual, flexible and differentiated manner to reduce the negative impacts of population aging17. Changing fertility and retirement policies are likely to have great effects on the population age structure and potentially influence household consumption and carbon footprints. Many studies have estimated the effect of population aging on carbon emissions in China, finding that population aging may reduce18, increase19,20 or have nonlinear effects on carbon emissions21. However, no study has assessed the impacts of policies that address population aging—including fertility (particularly the three-child policy) and retirement policies—on carbon emissions or household carbon footprints. Thus, we aim to address this gap in the literature. In this Article, we first investigate age-based household carbon footprints in China and its provinces by compiling a global multiregional input–output (MRIO) table and employing a large-scale household survey. We further estimate the age distribution of the population in China and its provinces up to 2060 by using a cohort-component method and then assess the impacts of fertility and retirement policies on household carbon footprints. Age-based household carbon footprint The total and per ca (...truncated)