The troposphere What humans affect most

The troposphere is the layer where our weather occurs. It s also the layer that takes the brunt of both natural and man-made pollution because of its proximity to the earth. 

Nature pollutes the atmosphere to a certain extent — with noxious hydrogen sulfide (H2S) and particulate matter from volcanoes, and the release of 

Above the troposphere is the stratosphere, which is where jets and high-altitude balloons fly. The atmosphere is much thinner in this layer because of the decreasing pull of gravity. Few of the heavier pollutants are able to make it to the stratosphere, because gravity holds them tight and close to the surface of the earth. The protective ozone layer resides in the stratosphere this protective barrier absorbs a large amount of harmful ultraviolet (UV) radiation from the sun and keeps it from reaching the earth. 

Even though heavier pollutants don t make their way to the stratosphere, this layer isn t immune to the effects of mankind. Some lighter manmade gases do make it into the stratosphere, where they attack the protective ozone layer and destroy it. This destruction can have far-reaching effects on humans because UV radiation is a major cause of skin cancer. 

A chemical substance can be both a good guy and a bad guy. The only difference is where, and in what concentration, it s found. For example, a person can overdose on water if he or she drinks enough of it. The same goes with the ozone in the stratosphere. On one hand, it shields us from harmful UV radiation. But on the other, it can be an irritant and destroy rubber products (see Brown Air (Photochemical Smog) for details). 

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