Greenhouse effect definition

VOCs, which are present mainly in the gas phase, play important roles in a range of environmental issues. These important roles involve their global greenhouse effect, their toxic or carcinogenic human health effects, their accumulation and persistence in the environment, and their role in secondary aerosol formation. The definition of VOC is often very diffuse. In physicochemical terms, the term VOC refers to those organic compounds that are present in the atmosphere... 

The effects of transport on economy, people and on the environment are manifold. They include the consequences of transport accidents and fatalities, nuisance and health effects caused by steady noise exposure, air emissions and the exhaust and resuspension of particles, climate impacts by the emission of greenhouse gases, soil and water contamination, and the deterioration of natural habitats. Moreover, the financial burden of infrastructure provision and the additional travel and production costs caused by congestion should be mentioned but these items are mainly borne by transport users themselves and thus are only partly imposed on society as a whole. Not all of these effects are equally relevant for all means of transport. While accidents constitute the major problem of car travel, the railways definitely face a noise problem and air transport contributes most to the emission of climate gases. 

The definite amount of greenhouse gases in the atmosphere has yet to be calculated. It depends on population, the per capita consumption of fossil fuel, deforestation, forestation activities and countermeasures that balance the extra carbon dioxide in the air. This could include planting more trees. Another factor is the use of alternative energy and conservation. Trades in fuel carbon will also have an effect. Transfers may occur from coal-rich to coal-poor nations. 

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