1  Mobile combustion

1.1 Introduction

Transportation emissions, when grouped together, are one of the largest sources of greenhouse gas emissions nationally, statewide, and locally.

This is the transportation section for estimating on-road emissions. Modes included are motorcycles, passenger cars, intercity buses, light commercial trucks, single unit long-haul trucks, refuse trucks and transit buses. Aviation data provided are considered preliminary at this time.

Note that this does not include freight rail, light rail, and other transportation emissions.

1.2 2021 emissions

Transportation emissions totaled 15.59 MMtCO₂e, accounting for 32% of regional emissions in 2021.

Figure 1.1: 2021 transportation emissions by county

We can also view this data broken out by fuel type.

Figure 1.2: 2021 annual emissions transportation by fuel type

1.3 Historical emissions

Despite a 10.3% reduction in the transportation sector due to the Covid pandemic, emissions in this sector rebounded to in 2021.

Figure 1.3: Transportation emissions, 2002-2021