How population aging affects carbon footprints in US households: a comparative study with Japan

• Published in: Environmental Research Communications Vol. 6; no. 10; pp. 105021 - 105030
• Main Authors: Wang, Jiahuan, Huang, Yuzhuo, Long, Yin, Chapman, Andrew, Shigetomi, Yosuke
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01-10-2024
• Subjects: Age; Aging; Brackets; Carbon; Carbon footprint; Comparative studies; Decarbonization; Demographic projections; Demographics; Demography; Developed countries; environmental input–output analysis; Footprint analysis; household consumption; Households; Immigration; Input output analysis; Population studies; Regional development; United States; United States > US; Japan
• ISSN: 2515-7620; 2515-7620
• DOI: 10.1088/2515-7620/ad84a7

Abstract Demographic aging has emerged as a global societal concern, posing a challenge to decarbonization efforts. This study investigates the impact of demographic aging on household decarbonization by first quantifying age-bracket-specific household carbon footprints (HCF) in the United States (U.S.), and comparing them to Japan, a country facing the most serious aging issues among economically developed countries. To explore future challenges, an estimation of the effects of demographic shifts on HCFs to the late 2030’s using multi-regional input-output analysis. It was revealed that the highest per-capita HCF was associated with middle-aged (45–54) households, reaching 31.9 t-CO 2 eq/cap in the U.S., more than double the same age bracket in Japan. Due to an influx of younger immigrants in the U.S., future demographic changes are projected to increase the total HCF by 684.5 Mt-CO 2 eq from 2011 to 2038. In contrast, Japan is expected to see a decrease of 28.4 Mt-CO 2 eq from 2011 to 2040. The comparison between the U.S. and Japan highlights two distinct pathways resulting from future demographic trends, underscoring the need for CF mitigation efforts to target U.S. household demand specifically. In response to this, policy recommendations are proposed to reduce HCFs in the U.S., particularly in light of its aging and immigration challenges.