Elucidate dynamics of tropospheric ozone and nitrogen oxides using triple oxygen isotopic compositions of nitrogen oxides as tracers

Abstract

Tropospheric ozone is not only the third largest greenhouse gas in terms of radiative forcing, but it also acts as a photochemical oxidant, controlling the oxidative capacity of the atmosphere, and has a significant impact on the atmospheric environment and ecosystems. Tropospheric ozone is produced primarily through the photodissociation of nitrogen dioxide, which is produced by the reaction of nitric oxide with peroxy radicals. Therefore, without understanding the process by which nitrogen dioxide is produced, it is impossible to quantitatively understand where and how tropospheric ozone is produced and consumed. In this study, we used the triple oxygen isotopic compositions as an indicator to directly quantify the contribution of peroxy radicals to the overall nitrogen dioxide production reactions in the atmosphere, and attempted to estimate the net ozone production.