Impact of newly extended metro line opening on commuting carbon emissions: A comparative study before and during the pandemic

Abstract

Urban transportation is a key contributor to greenhouse gas emissions. Given that metro systems serve as prominent modes of public transportation, it becomes imperative to investigate the alteration in carbon emissions subsequent to the inauguration of new metro lines, along with the determinants influencing the metro commuting choices. Previous research tends to use surveys to collect individual travel data, which may have sample selection and self-reported data problems. This research combines big data and survey method to study commuting carbon emission change and influencing factors of metro adoption. Because COVID-19 also has an impact on individual commuting mode, this research further explores total and per capita carbon emissions before and during the pandemic period. Selecting Shenzhen metro lines as a study case, it is found that the opening of newly extended metro lines leads to an increased proportion of residents commuting by metro and a decreased proportion of car users, resulting in a reduction of commuting carbon emissions. Additionally, during the pandemic, people tended to choose private cars for commuting due to its advantage of independence and privacy, resulting in an increase in commuting carbon emissions. Finally, regarding influencing factors of metro adoption, it is also found that young and middle-aged, highly educated, low-income residents or residents without cars are more likely to choose metro as their commuting mode. This research suggests the local government promote public transit after the pandemic period and tailor transport policies for the various resident groups, including providing subsidies.

Keywords

• Communte
• Travel behavior
• Carbon emissions
• Metro