Environment ozone depletion

The more common requirement to control routine disposal and dispersion of solid, liquid or gaseous pollutants is based upon different criteria, e.g. their persistence in the environment (as with the effects attributed to ozone-depleting gases, or the problem of heavy metal contamination... 

Tonnage of air emissions, water emissions and liquid and solid effluent and tonnage of hazardous materials released into the environment. These two measures are related to one another. However, the first measure relates the total effluent, including nonpolluting materials. The second measure looks only at the tonnage of hazardous materials contained in the total effluent. Both measures can be important indicators. For example, for solid waste it is important to know the total volume of material for disposal and different upstream treatment techniques may affect the total volume. However, for ozone depleting chemicals, only the quantity of these gases is important and other components such as water vapor may be irrelevant. 

The CFC-ozone depletion issue has demonstrated that mankind has the potential to seriously modify the atmosphere on a global scale. We need to learn much more about the environment to prevent its inadvertent deterioration by human activities. 

Effect of UV on Productivity of the Southern Ocean. Has ozone depletion over Antarctica affected the productivity of the Southern Ocean There is no easy answer. First, one has to take into account the fact that the drastic decrease of ozone over Antarctica has been reported as recently as 1976, a relatively short time in the evolution of the organisms to develop mechanisms to cope with elevated UV. One of the most vexing problems in studying the effects of UV radiation on productivity, is a dearth of historical data on the level of UV. Without these baselines, normal fluctuations could easily be interpreted as decline in productivity. Second, there is a host of biotic and abiotic factors that play significant roles in governing the productivity of the Southern Ocean (40). Ultraviolet radiation is but one more complicating factor to be considered in an already stressful environment. 

Nitrous oxide has received increasing attention the last decade, due to the growing awareness of its impact on the environment, as it has been identified as an ozone depletion agent and as a Greenhouse gas [1]. Identified major sources include adipic acid production, nitric acid and fertilizer plants, fossil fuel and biomass combustion and de-NOx treatment techniques, like three-way catalysis and selective catalytic reduction [2,3]. 

The life cycle impact assessment (LCIA) is used to assess the results of the LCA and evaluate the impact on the environment in the various impact categories. These impact categories include, for example, human health, GWP, energy, water use, eutrophication, ozone depletion, aquatic toxicity, and land use (ISO, 2006b). LCA may focus on one or more impact categories. The results may be normalized, weighted, and aggregated in optional steps of the LCIA for comparison to political objectives, for example. In addition, sensitivity analyses are often conducted over the entire LCA to evaluate the variation in the results due to selected factors. 

Laturnus F, Svensson T, Wiencke C, Oberg G (2004) Ultraviolet radiation affects emission of ozone-depleting substances by marine macroalgae results from a laboratory incubation study. Environ Sci Technol 38 6605-6609... 

This is probably the key heterogeneous reaction for Antarctic stratospheric ozone depletion, and serves as a useful focus for the discussion of the theoretical challenges that must be addressed in dealing with fairly complex chemistry in a complex environment, challenges enlivened — as will be seen below — by the evident chemical involvement of the ice surface environment. 

Nimitz, J. S., and S. R. Skaggs, Estimating Tropospheric Lifetimes and Ozone-Depletion Potentials of One- and Two-Carbon Hydrofluorocarbons and Hydrochlorofluorocarbons, Environ. ScL Technol., 26, 739-744 (1992). 

Wuebbles, D. J., A. K. Jain, K. O. Patten, and P. S. Connell, Evaluation of Ozone Depletion Potentials for Chlorobro-momethane (CH2CIBr) and 1-Bromopropane (CH2BrCH2CH,), Atmos. Environ., 32, f07— 113 (1998). 

The health risks associated with ozone depletion will principally be those due to increased ultraviolet-B (UV-B) radiation in the environment, that is, increased damage to the eyes, the immune system, and the skin. Some new risks may also be introduced with the increased use of alternatives to the ozone-depleting substances (ODSs). However, the data are insufficient to develop similar estimates for effects such as immunosuppression and the toxicity of alternatives. 

Using data on the mass efficiency and energy requirements of the processes, an estimate of the potenhal impact on the environment was undertaken. Key areas of public concern are greenhouse gas emissions, generation of acid rain, and any impact/effect on ozone depletion. In all of the areas evaluated, in particular the key areas of public interest, route 4 has significant environmental benefits, with reductions in emissions of between 60 and 80%. 

Nimitz, J.S. and S.R. Skaggs. 1992. Estimating tropospheric lifetimes and ozone-depletion potentials of one- and two-carbon hydrofluorocarbons. Environ. Sci. Technol. 26 739-744. 

Chemistry and the Environment is designed to intentionally motivate and engage students by connecting basic chemical principles and civic engagement through public issues such as air quality, ozone depletion,... 

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