9781422272480

Many large cities around the world have smog. The polluted air can reduce visibility and cause breathing issues.

atmosphere that our radio and GPS signals travel through. The Ozone Ozone is a reactive gas that is made up of three types of oxygen atoms. It occurs within both the stratosphere (the upper atmosphere) and the troposphere (the lower atmosphere). It is both natural and man-made. It is formed naturally inside of the stratosphere when UV radiation from the sun interacts with molecular oxygen, which reduces the levels of radiation that reach the surface of the earth. Ground-level ozone is present in the air that we breathe. It is formed when two different kinds of air pollutants combine and interact. These reactions between pollutants tend to be higher in locations where temperatures are higher. This is one of

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Atmosphere