[Development of a Non-Road Mobile Source Emissions Inventory for Tianjin]

Based on the collected data of activity level in 2015, a non-road mobile source emissions inventory for Tianjin was developed following the recommended method from the Compilation Guide for a Vehicle Emissions Inventory (trial edition) released by the Ministry of Environmental Protection. In 2015, the emissions of CO, hydrocarbons (HC), nitrogen oxides (NO), particulate matter (PM) and SO₂ from non-road mobile sources in Tianjin were 6.15×10³ t, 2.45×10³ t, 2.90×10⁴ t, 1.45×10³ t, and 1.37×10⁴ t, respectively. Marine sources were identified as the largest non-road mobile source contributor accounting for 73.66% of total emissions, followed by non-road mobile machinery (21.66%). Emissions from civil aircraft and locomotives were relatively lower. Generally, emissions from non-road mobile sources increase from March (spring) to November and decrease from the beginning and the end of the year (winter). Emissions are mainly distributed in suburban districts where there is flourishing agriculture, downtown areas with dense populations, urban construction areas, ports, railway lines, and airports. Uncertainty in the inventory results is mainly due to the lack of key data, such as local emission factors and actual activity levels.