Ozone sensitivity to high energy demand day electricity and onroad emissions during LISTOS
Year: 2024
Type: article
Abstract: Using a high-resolution, 1.33 km by 1.33 km coupled Weather Research and Forecasting-Community Multi-scale Air Quality Model (WRF-CMAQ), we quantify the impact of emissions of nitrogen oxides (NOx) from high energy demand day (HEDD) electricity generating units (EGU) and on-road vehicles on ambient ozone air quality in the Long Island Sound Tropospheric Ozone Study (LISTOS) region covering New York City (NYC); Long Island, NY; coastal Connecticut; and neighboring areas. We test sensitivity scenarios to quantify HEDD EGU NOx contributions to ozone: (1) zero out HEDD EGU emissions, (2) dispatch HEDD EGUs starting with the lowest NOx emitting units first, (3) reduce onroad emissions by 90%, (4) combine zero out HEDD EGU emissions and reducing onroad emissions by 90%, and (5) dispatch HEDD EGUs starting with the lowest emitting units coupled with a reduction in on-road emissions by 90%. Results determine HEDD EGUs lead to highly localized impacts on ambient concentrations of ozone while on-road emissions reductions lead to large-scale regional concentration impacts. Further, reducing on-road emissions by 90% leads to spatially smaller VOC-limited regions and spatially larger transitional and NOX-limited regions around NYC. Despite the limited scale at which the EGU emissions reductions occur, modifying HEDD EGU NOX emissions still provides substantial benefits in reducing ozone concentrations in the region, particularly at elevated ozone concentrations above 70 ppb.Implication Statement High-resolution coupled meteorology-chemistry modeling in the New York City and surrounding areas is used to model changes in ozone air quality resulting from region-wide onroad transportation emission reductions and NOX reductions from high energy demand day (HEDD) electricity generating units (EGUs). Although reducing onroad emissions by 90% produces the largest change in ozone concentrations, the results also suggest that the ozone photochemical regime becomes more NOx-sensitive as emissions from major regional sectors like onroad transportation continue to decline. Despite being highly localized and variable, emissions from HEDD EGUs can have an added impact on reducing ambient ozone concentrations. As the ozone production regime in the region shifts from VOC-sensitive to NOx-sensitive, the impacts of NOx-titration in the urban core weaken and ozone is more likely to decline with a decrease in NOx emissions such as from HEDD units.
Authors: Alexandra Karambelas, Paul J. Miller, Jeffrey Underhill, Jonathan Pleim, Eric Zalewsky, Joseph Jakuta
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4401877011