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Many of our most severe problems of environmental pollution involve the Earth's atmosphere. The adverse effects of atmospheric pollution are particularly evident in the low troposphere, especially in urban/suburban areas where many sources contribute to th ...
The temporal and spatial retrieve of ozone (O3) concentration and water vapor (H2O) mixing ratio in the troposphere is of essential interest. Contrary to the stratospheric case, the tropospheric ozone can have a harmful impact, with its toxic effect, on hu ...
Numerical simulations compared with field measurements are used to explain the effect of sea breezes on photochemical smog episodes in Athens during the Mediterranean Campaign of Photochemical Tracers on 12-14 September 1994. The numerical simulations, per ...
The influence of temperature, pH, alkalinity, and type and concentration of the dissolved organic matter (DOM) on the rate of ozone (O-3) decomposition, O-3-exposure, . OH-exposure and the ratio R-ct of the concentrations of . OH and O-3 has been studied. ...
The long-time evolution of monopolar and dipolar vortices influenced by the large-scale gradient of the ambient potential vorticity (the beta-effect) is studied by direct numerical solutions of the equivalent barotropic quasi-geostrophic equation. Translat ...
Measurements of local air pollution and road traffic were taken during a period of one month before and after the opening of a road tunnel to the public in nearby Sachseln, a small city located in a rural region (Obwald) at the center of Switzerland. Two 5 ...
The influence of carbonate on the ozone/hydrogen peroxide process has been investigated. Carbonate radicals, which are formed from the reaction of bicarbonate/carbonate with OH radicals, act as a chain carrier for ozone decomposition due to their reaction ...
A new lidar for the measurement of tropospheric ozone is proposed, based on the differential analysis of the Raman backscattered signals on nitrogen and oxygen, which is far less sensitive to the aerosols than the classical DIAL system. Using a third Raman ...
A new way of measuring ozone and water vapor in the Planetary Boundary Layer (PBL) is proposed. The method is based on the simultaneous measurement of the Raman backscattering in the UV by O2, N2 and H2O, using a single pump beam at 266 nm. The ozone conce ...
The ozonation of model systems and several natural waters was examined in bench-scale batch experiments. In addition to measuring the concentration of ozone (O-3), the rate of depletion of an in situ hydroxyl radical probe compound was monitored, thus prov ...