
Опубликована: Дек. 13, 2024
Abstract. Surface ozone, with its long enough lifetime, can travel far from precursor emissions, affecting human health, vegetation, and ecosystems on an intercontinental scale. Recent decades have seen significant shifts in ozone emissions: reductions North America Europe, increases Asia, a steady global rise methane. Observations Europe show declining trends, flattened seasonal cycle, shift peak summer to spring, increasing wintertime levels. To explain these changes, we use TOAST 1.0, novel tagging technique implemented the atmospheric model CAM4-Chem which attributes emissions fully by NOX or VOC+CO+CH4 sources perform multi-decadal simulations for 2000–2018. Model-simulated maximum daily 8 h (MDA8 O3) agrees well rural observations TOAR-II database. Our analysis reveals that local contributions peak-season (PSO) are offset rising natural (due increased productivity), foreign anthropogenic- international shipping due emissions. Transported dominates during spring. Methane is largest VOC contributor PSO, while NMVOCs become more important summer. Contributions anthropogenic remain smaller than those NOX. Despite methane levels, contribution PSO has declined
Язык: Английский