The new CHEM2D-Ozone Photochemistry Parameterization (CHEM2D-OPP) for high-altitude numerical weather prediction (NWP) systems and climate models specifies the net ozone photochemical tendency and its sensitivity to changes in ozone mixing ratio, temperature and overhead ozone column based on calculations from the CHEM2D interactive middle atmospheric photochemical transport model. We evaluate ...

[1] Continuous surface-layer ozone flux measurements over the polar, year-round snowpack at Summit, Greenland, resulted in deposition velocities (vd) that were smaller than most previous assumptions and model inputs. Substantial seasonal differences were seen in the ozone vd behavior. Spring, daytime ozone vd values showed low variability and were consistently 0.01 cm s . During summer, ozone f...

Surface ozone pollution has been a persistent environmental problem in the US and Europe as well as the developing countries. A key prerequisite to find effective alternatives to meeting an ozone air quality standard is to understand the importance of local anthropogenic emissions, the significance of biogenic emissions, and the contribution of long-range transport. In this study, an air qualit...

The factors involved in evaluations of effects of volatile organic compound (VOC) and oxides of nitrogen emissions from motor vehicles on ground-level ozone are reviewed. The chemical basis for ozone formation, the computer models and chemical mechanisms used for predicting ozone impacts, and methods for quantifying differences among VOCs in their ozone impacts, are discussed. It is recommended...

Laboratory design of an ozone concentration regulator which is build on the theory of continuity equation for gas flow in parallel pipes in conjunction with the ozone elimination potentials of an ozone destructor is presented. At an initial oxygen flow rate of 33.33 cms, ozone concentration was generated and varied between 429.30 parts per million (ppm) to 3826.60 ppm. Similarly at an initial o...

BACKGROUND Mechanisms of cardiovascular injuries from exposure to gas and particulate air pollutants are unknown. OBJECTIVE We sought to determine whether episodic exposure of rats to ozone or diesel exhaust particles (DEP) causes differential cardiovascular impairments that are exacerbated by ozone plus DEP. METHODS AND RESULTS Male Wistar Kyoto rats (10-12 weeks of age) were exposed to ai...

Inexpensive devices to measure solar UV irradiance are available to monitor atmospheric ozone, for example, total ozone portable spectroradiometers (TOPS instruments). A procedure to convert these measurements into ozone estimates is examined. For well-characterized filters with 7-nm FWHM bandpasses, the method provides ozone values (from 304- and 310-nm channels) with less than 0.4% error attr...

[1] The spatial and temporal variation in ozone production over major source regions in East Asia during the NASATransport and Chemical Evolution over the Pacific (TRACE-P) measurement campaign in spring 2001 is assessed using a global chemical transport model. There is a strong latitudinal gradient in ozone production in springtime, driven by regional photochemistry, which rapidly diminishes a...

Atmospheric Chemistry and Physics Discussions This discussion paper is/has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP if available. Abstract The decrease of the concentration of ozone depleting substances (ODS) in the stratosphere over the past decade raises the question to what extent observed changes in strat...

Ozone is an air pollutant that causes pulmonary symptoms. In mice, ozone exposure causes pulmonary injury and increases bronchoalveolar lavage macrophages and neutrophils. We have shown that IL-17A is important in the recruitment of neutrophils after subacute ozone exposure (0.3 ppm for 24-72 h). We hypothesized that γδ T cells are the main producers of IL-17A after subacute ozone. To explore t...