This study investigates the origin of a commonly observed feature in the O3 profiles: mid tropospheric O3 maxima (300–500 hPa) over the tropical Indian Ocean. A comparison and analysis of model simulations, using a 3-D global climate-chemistry model, and measured O3 profiles from the INDOEX campaign is presented. European Centre for Medium-Range Weather Forecast (ECMWF) meteorological analyses ...

Aviation NOx emissions promote tropospheric ozone formation, which is linked to climate warming and adverse health effects. Modeling studies have quantified the relative impact of aviation NOx on O3 in large geographic regions. As these studies have applied forward modeling techniques, it has not been possible to attribute O3 formation to individual flights. Here we apply the adjoint of the glo...

Spring wheat (Triticum aestivum L., cv. ‘Minaret’) was grown in open-top chambers and exposed to two CO2 concentrations (ambient and 680 ppmv) and two O3 concentrations (ambient and ambient +50 or +90 ppbv) either from anthesis onwards or for the entire growing season. The aim of the experiment was to test whether elevated CO2 could provide ‘protection’ to the crop against the damaging effects ...

After sunset, a stable boundary layer (SBL) develops close to the ground, while the upper region of the daytime mixed layer becomes the residual layer (RL). Mixing between the SBL and RL is often quite limited and the RL is thought to be a reservoir for daytime mixed-layer pollutants under such conditions. However, ozone (O3) profiles observed in Maryland, U.S. suggest that the RL is not always...

Overwhelming evidence has shown that, from the Industrial Revolution to the present, human activities influence ground-level ozone (O3) concentrations. Past studies demonstrate links between O3 exposure and health. However, knowledge gaps remain in our understanding concerning the impacts of climate change mitigation policies on O3 concentrations and health. Using a hybrid downscaling approach,...

It has been reported that ambient ozone (O3), either alone or in concurrence with acid rain precursors, accounts for up to 90% of US crop losses resulting from exposure to all major air pollutants. Crop damage due to O3 exposure is of particular concern as ambient O3 concentrations remain high in many major food-producing regions. Assessing O3 damage to crops is challenging due to the difficult...

The productivity, product quality and competitive ability of important agricultural and horticultural plants in many regions of the world may be adversely affected by current and anticipated concentrations of ground-level ozone (O3). Exposure to elevated O3 typically results in suppressed photosynthesis, accelerated senescence, decreased growth and lower yields. Various approaches used to evalu...

More effective techniques are required to mineralize the increasing number of recalcitrant organic contaminants at low concentrations in the water environment using advanced oxidation process. Though relatively new, photocatalytic ozonation (O3/UV/TiO2) is considered superior to ozonation (O3) and photocatalysis (UV/TiO2), due to synergistic effects and use of immobilized TiO2 photocatalysts is...

Acute exposure to ozone (O3) enhances pulmonary chemoreflex response to capsaicin, and an increased sensitivity of bronchopulmonary C-fiber afferent endings may be involved. The present study was aimed at determining the effect of O3 on the responses of pulmonary C fibers to chemical and mechanical stimuli. A total of 31 C fibers were studied in anesthetized, open-chest, and vagotomized rats. D...