Ozone variation over tropics: Trends revealed from Dobson measurement over Indian stations

. Variations in ozone amounts have been studied using data obtained with Dobson spectrophotometers during 1966-1988 at Srinagar, New Delhi, Pune and Kodaikanal. Yearly average values of total ozone , and its vertical distribution by the Umkehr method in layers 1 to 9 have been computed. Departures from compo- site avarage value for the period (1966-1988) have been computed for both total ozone and its vertical distribution. The variation over New Delhi and Pune have been compared with those at Arosa reported by Dutsch {1989). The observed variations in the ozone distribution at New Delhi and Pune can be explained, as being within normal interannual changes. Tropospheric ozone in layer lover New Delhi shows some effects of an anthropogenic nature, on the other hand Pune does not exhibit in any influence of pollutants in any layer, either in the troposphere or stratosphert.

Plasma-Ozone Treatment of Air Supply on Performance and Emissions of Diesel Engine

In improving performance and reducing exhaust emissions in combustion engines, the addition of ozone to the air supplied in the combustion chamber was studied. In this research, ozone can be produced using plasma technology (plasma-ozone) which is a simple and eco-friendly technology. Plasma-ozone was generated using the Dielectric Barrier Discharge (DBD) method. Air is passed in plasma-ozone reactors at different voltages with an ozone variation of 3 mg, 12 mg, 15 mg and 18 mg is obtained. Ozone concentration was detected using an Ozone meter O3 Air Quality Detector and OPA-100 was used to determine exhaust emissions. The result showed that the addition of ozone to the air supply has no significant effect on brake power but is able to increase specific fuel consumption, increase cylinder pressure, shorten combustion processes, and reduce heat release values. The addition of ozone decreases the opacity of exhaust emissions in TV-1 diesel engines become more eco-friendly.

Assessment of Meteorological Effects and Ozone Variation in Urban Area

The paper presents results of the measurements of the tropospheric ozone (O3) concentration and meteorological parameters: temperature, air pressure, relative humidity, speed and wind direction. The data were collected from January 2016 to December 2016 at station located in locality Centre (Banja Luka), Republic of Srpska, Bosnia and Herzegovina. Ozone is one of the most harmful pollutants to plants and health and highly reactive secondary pollutant. The present study covers investigation of the relationship between the concentration of ozone and meteorological parameters as well as time variations of ozone concentration (by hours, months, seasons). This topic has not been studied up to now in this region, although the recent research data indicates that there is a correlation between them and previously obtained from the world’s relevant scientific centres, as already cited above. Statistical analysis confirms string of rolls, which shows directional connection between tropospheric ozone and meteorological parameters, specially temperature (r = 0.148), air pressure (r = –0.292) and relative humidity (r = –0.292). These parameters are the most important meteorological factors influencing the variation in ozone levels during the research. The correlation ozone concentrations with speed and direction of wind is not significant, like other parameters.

A Case Study of Ozone Diurnal Variation in the Convective Boundary Layer in the Southeastern United States Using Multiple Observations and Large-Eddy Simulation

We investigated the diurnal ozone variation on 6 September 2013 in a midsize urban environment using multiple in situ and remote-sensing measurements along with the Dutch atmospheric large-eddy simulation (DALES) model coupled with a chemical module and a dry deposition module that we added for this study. Our study area was Huntsville, Alabama, USA, a typical midsize city in the Southeastern United States. The ozone variation in the convective boundary layer (CBL) resulted mainly from local emissions and photochemical production stemming from weather conditions controlled by an anticyclonic system on that day. Local chemical production contributes approximately two thirds of the ozone enhancement in the CBL and, in this case, dynamical processes including ozone transport from the free troposphere (FT) to the CBL through the entrainment processes contributed the remainder. The numerical experiments performed by the large-eddy simulation (LES) model showed acceptable agreement with the TOLNet (The tropospheric ozone lidar network)/RO3QET (Rocket-city ozone quality evaluation in the troposphere) ozone DIAL (differential absorption lidar) observations. This study indicated the need for fine-scale, three-dimensional ozone observations with high temporal and spatial resolution for air quality studies at the urban scale and smaller.