Regional Impact of Ozone Precursor Emissions on NO_X and O₃ Levels at ZOTTO Tall Tower in Central Siberia

Abstract

Measurements of ozone (O 3 ) and its precursors, including NO X species (NO X = NO + NO 2 ), allow assessment of the current state of the tropospheric photochemical system (TPS), as well as long-term trends in chemical air composition associated with the changing climate and strength of air pollution sources. Ozone is a key compound of the TPS, whose photolysis initiates most of the chemical reactions through generating an excited atomic oxygen O( 1 D). A subsequent reaction of O( 1 D) with a molecule of water (H 2 O) is the principal source for the tropospheric hydroxyl radical OH which drives oxidation of relatively stable ozone precursor species [e.g., carbon monoxide (CO), methane (CH 4 ), and higher molecular mass hydrocarbons (NMHC)] emitted from various natural and anthropogenic sources. Also, O 3 is an important secondary pollutant whose mixing ratios above 40-60 ppbv are harmful to human health (

Insights on Air Pollution During COVID-19: A Review

“…The sudden restriction in human activities, industrial emissions, and vehicular emissions reduce the NOx emission resulting change in AOC. The atmospheric oxidation governs via VOCs, NO x (NO + NO 2 ), and HO x (OH + HO 2 ) concentration levels over a region (Lelieveld et al 2008 ; Moiseenko et al 2021 ; Wang et al 2021a ). During the lockdown period, NO X is reduced manifold (> 45%) of time over different cities of the world (Singh et al 2020 ; Shehzad et al 2020 ).…”