Quantifying the Co-benefits of Air Pollution and Greenhouse Gas emission mitigation by operating Metro Line 1 in Ho Chi Minh City, Vietnam

Abstract

Abstract Motorcycles, cars, and buses in urban areas contribute significantly to greenhouse gas (GHG) emissions and air pollutants. Particularly, Ho Chi Minh City (HCMC) has the highest vehicle traffic intensity in Vietnam. To improve the traffic system, HCMC has implemented urban railway projects, and this research aims to quantify the co-benefits of these public transport systems. The study used the EMISENS model and the TAMP-EARMOD simulation model system to assess the current situation and to predict the GHG and air pollution emissions when Metro Line 1 (Ben Thanh – Suoi Tien) operates stably. The reduction of air pollution and GHG is calculated to identify the co-benefits when a part of personal transport means is substituted by Metro Line 1. The results show that, if Metro Line 1 is put into operation and reaches 80% of its transport capacity, the air emissions on the route parallel to Metro Line 1 decrease 429.94 tons/year, 13,639.32 tons/year, 11.36 tons/year, 1,137.84 tons/year, 24.27 tons/year for NOx, CO, SO2, NMVOC, and PM2.5, respectively. Importantly, the emission of CO2eq reduces above 49.6 million tons per year, equivalent to 25.4%. Based on these results, the study proposes measures to optimize the deployment of Metro Line 1 to maximize the attainment of co-benefits.