How Do Aviation Local Emissions Compare To Other Transportation Sources?

Aviation has grown faster than other modes of transportation and is expected to outpace them in the future. Despite this growth, aviation’s contribution to local air quality inventories compared to other transportation sources has remained modest. 

For example, as the chart shows, the rate of growth in aviation NOx emissions has far outpaced on-road (i.e., cars and trucks) NOx emissions growth. 

However, as the next chart shows, the quantity of emissions of other transport modes far exceeds aviation’s NOx contribution. 

This is not surprising as most of an aircraft’s operations take place at altitude where emissions do not affect local air quality. This is in contrast to cars and trucks that primarily operate within a single air quality region and always at ground level. 

In the future, NOx emissions from on-road vehicles should fall in response to the most recent environmental regulations. Aircraft, on the other hand, will be challenged to reduce their total NOx emissions.

However, even if the other sources were able to reduce their emissions by half, a highly unlikely occurrence, aviation NOx emissions would still be less than 3 percent of the transportation NOx inventory by 2020. 

Nonetheless, pressure on aviation sources will likely remain as many states and localities will face the twin challenges of meeting new ozone and particulate matter standards at the same time non-aviation source reductions become more difficult and costly.

• What emissions come from aviation?

• What determines aviation emissions?

• What have been the trends in aviation emissions?

• How do aviation emissions compare to general trends in local air pollutants?

• How do aviation local emissions compare to other transportation sources?

• Can a comparison be made between aviation emissions and non-transportation sources?

• What role does aviation emissions play with regard to greenhouse gas issues?

• How do aviation’s greenhouse gas emissions compare to other transportation sources?

• How are aviation emissions regulated?

• What is being done today to reduce aviation emissions?

• What steps are being taken to reduce aviation emissions in the longer-term?