Choosing between Global and Local Emission Control Strategies in Urban Transport Sector, Which way to go?

Cities are engrossed with response strategies for the control of local pollution from transport sector. However, as the transport sector has been growing as major GHG contributor, and there is an increasing scope for investment and support from the international financial institutions, cities often get into confusion on whether to go by local emission control strategies (LEMS) or adopt GHG mitigation strategies (GEMS).
This paper presents a comparison between GHG mitigation strategies and local emission control strategies and their potential in controlling non-target pollutant emissions in concurrence with their economic performance. Comparative analysis based on multiple constraint optimization model for Mumbai transport system planning for the next 20 years and incremental cost analysis had revealed that strategies targeting the mitigation of total suspended particulate matter (TSP) could also reduce carbon dioxide (CO2) emissions (as non-target emission) and vice-versa. Co-benefits of emission reduction from local emission control strategies are higher compared to that of GHG mitigation strategies.
In the incremental cost analysis, both GHG mitigation strategies and local emission control strategies were found performing comparably. Thus, local emission control strategies with better emission reduction potential and also better local acceptance are more favourable than GHG mitigation strategies in long term transportation planning. Therefore, it is recommended that the development projects in urban transportation planning and management may consider local emission control strategies rather than GHG mitigation strategies. The co-benefits (CO2 reduction) of local emission control strategies would still play the attraction for international funding agencies to invest in transport sector and also for CDM opportunities.