Japanese urban household carbon footprints during early-stage COVID-19 pandemic were consistent with those over the past decade

Abstract

As urbanization accelerates worldwide, substantial energy and services are required to meet the demand from cities, making cities major contributors to adverse environmental consequences. To bridge the knowledge gap in the absence of fine-grained city-level climate protection measures due to data availability and accuracy, this study provides a detailed carbon emission inventory for analyzing the monthly fluctuations based on citizens’ daily consumption behaviors. Here, carbon emissions embodied in approximately 500 household consumption items were calculated in 47 prefectural-level cities in Japan from 2011 to June 2021. We analyzed the results considering the regional, seasonal, demand, and emission way-specific aspects, and compared the emission before and during the COVID-19 pandemic. Notably, the carbon footprints during the pandemic were consistent with the previous level despite downtrends in specific categories. This study provides an example of utilizing city-level emission data to improve household green consumption behavior as references for enriching city-level decarbonization paths.

Extension and update of multiscale monthly household carbon footprint in Japan from 2011 to 2022

“…A previous study identified gasoline, kerosene, LPG, and city gas as the primary fossil fuels responsible for direct emissions from Japanese households 41 , 54 . The fundamental principles for calculating the direct emissions from the use of different fuels are presented here.…”

“…To validate the accuracy of our study, we consulted carbon footprint data from several government agencies, including the GHG Emissions Data of Japan from the Greenhouse Gas Inventory Office of Japan (GIO) 68 at the National Institute for Environmental Studies (NIES), the National Household CO 2 Survey from the Japan Society of Energy and Resources, and a previous study 54 . The detailed results of these comparisons by year and month are shown in Fig.…”