Abstract

Air quality regulators have been actively working to tackle the issue of ozone pollution in urban
areas since the 1950s. However, despite their persistent efforts, a substantial portion of the
American population continues to reside in locales designated as non-compliant with the
Environmental Protection Agency's ground-level ozone standards. In the past, nitrogen oxides
(NOx) and volatile organic compounds (VOCs) emitted predominantly through combustion,
particularly from vehicular sources, constituted the primary precursors driving ozone formation in
cities like Los Angeles. These anthropogenic combustion byproducts also exert a significant
influence on ozone chemistry in other urban settings, although a multitude of emission sources,
such as biogenic VOCs and NOx emissions from power plants, also contribute to this intricate
interplay.

As emission reduction programs have achieved success in reducing combustion related VOCs, a
category of VOCs known as Volatile Chemical Products (VCPs) has emerged as a significant
contributor, particularly in densely populated regions1. VCPs include personal care products,
cleaning products, fragrances, and solvents. Although the total amounts of VCPs used are small
compared to fossil fuels (e.g., gasoline), well over 90% of the VOCs evaporate into the air where
they can interact with other pollutants in the atmosphere, contributing to the formation of ozone.
However, the exact impact of VCPs emissions on air quality, specifically in relation to ozone
formation, remains poorly quantified1. Preliminary studies suggest that under certain conditions,
VCP emissions have the potential to enhance concentrations of ozone and secondary organic
aerosol.

Additionally, it is important to consider the influence of wildfire smoke on air quality and ozone
formation. Wildfires release substantial amounts of particulate matter and pollutants, including
VOCs and NOx, into the atmosphere contributing to poor air quality, affecting both urban and
rural areas. Given the increasing frequency of wildfires due to climate change, studying the effects
of wildfire smoke on air quality is becoming increasingly important2-3. Historically the Western
US has been affected by wildfire smoke much more than the rest of the US, however, June 2023
has been marked by dramatic impacts of wildfire smoke on air quality in the Mid-West and Eastern
US due to Canadian wildfires.

To comprehensively assess the influence of the above discussed phenomena on ozone formation
and concentrations, it is crucial to conduct extensive measurements of these compounds at specific monitoring sites. In line with this, we will be deploying the "ECHAMP" peroxy radical sensor to the CUNY Advanced Science Research Center in upper Manhattan during the summer of 2023 as part of the NOAA AEROMMA / NYC-METS family of projects. By measuring peroxy radicals, we will be able to quantify instantaneous ozone formation rates. Combined with measurements of VOCs (including PCPs and smoke-related compounds) we will be able to quantify the influence of PCPs and wildfire smoke on ozone formation in the greater NYC area.