A53T-02 Regional Differences in Surface Ozone and PM2.5 due to Aviation

Abstract

Air pollution is estimated to result in approximately 6.7 million premature mortalities annually, more than 74000 of which may be attributable to aviation emissions. Recent studies of aviation’s environmental impacts have solely focused on the climate impacts of aviation NO_x, suggesting they are small and uncertain relative to those of aviation CO₂. These analyses have neglected the air quality (AQ) impacts of NO_x, which previous studies have found to be substantial, and for which the monetized damages may be of a similar order of magnitude to aviation’s net climate impacts. The AQ impacts are due to surface population exposure to ozone and PM_2.5 due to local and transported emissions. To analyze this, prior studies have evaluated global average values of the sensitivity of changes in these parameters to emissions. However, a limitation of this approach is that it does not allow for a spatial differentiation of the impacts at high resolutions.

This work addresses this limitation by using a finite difference approach to determine the sensitivity of AQ impacts in regions of interest to aviation emissions at different regions. Simulations with a 0.5° x 0.5° resolution of the region of interest will enable analyzing the effect of the prevailing background conditions of that region on AQ, for which effects on climate have been explored. The GEOSChem High Performance global chemistry transport model with stretched-grid simulation capability will be used, which can model regions of interest at high resolution efficiently (Fig a) without significant increases in computational time. For our analysis, flights in aviation hotspots like North America, Europe, South Asia (Fig b) and in specific corridors (like flights from North America to Europe) (Fig c) will be chosen for aircraft and engines which have the largest share of impact. This aircraft-specific analysis will help shape aviation policies to minimize the environmental damages of aviation by understanding the impact of technology improvements on different types of aircraft. Furthermore, this high-resolution regional data will provide a foundation for analyzing the distributional inequities in aviation AQ impacts. Future work following this study will involve evaluating the total monetized impacts of aviation for damages due to both AQ and climate for different regions.
 

Plain-language Summary

Air pollution leads to about 6.7 million early deaths each year, with over 74,000 linked to aviation emissions. Recent research on aviation’s environmental impact has mainly focused on climate effects from aviation NO_x, finding them minor compared to aviation CO₂. However, these studies have overlooked the significant air quality impacts of NO_x, which can be just as damaging. These issues arise from exposure to ozone and PM_2.5 from local and distant emissions. Past studies looked at global averages for changes in these pollutants but didn’t capture detailed regional differences.

Our research fills this gap by using a new method to study how aviation emissions affect air quality in specific regions. We will run very high-resolution simulations to analyze how local conditions influence air quality. The GEOSChem High Performance model can efficiently simulate high-resolution areas without much extra computing time. We’ll focus on busy aviation areas like North America and South Asia, and major flight routes. By understanding how different aircraft impact the environment, we can help create policies to reduce aviation’s environmental harm. This detailed data will help analyze the fairness of air quality impacts from aviation and the overall financial damages by including climate impacts in different regions.