Q:

What is the benefit of the ozone layer?

A:

The ozone layer absorbs most of the biologically damaging ultraviolet radiation from the Sun, allowing only a small amount to pass. Through UV absorption, it creates a source of heat that defines the temperature characteristics of Earth's stratosphere. Left unfiltered, certain frequencies of UV radiation would more easily penetrate the protective coverings of organisms, causing severe damage to DNA molecules.

Ozone molecules consist of three oxygen atoms bonded together and make up only a trace amount of the total oxygen molecules in the air; there are approximately three ozone molecules for every 10 million air molecules. This scarcity stems from the fact that ozone molecules are highly reactive. They are present in another layer of the atmosphere closer to the surface called the troposphere, and their high reactivity causes these molecules to have a toxic effect on life-forms with which they come into contact.

The high reactivity has another consequence: the ozone layer is thinned by reactions with chlorofluorocarbons, molecules that were once widely used as aerosol propellants. As humans release these chemicals into the air, the molecules rise to the ozone layer and convert the oxygen in ozone into more stable forms, allowing more UV radiation to pass through the Earth's atmosphere.

Experts commonly classify UV radiation into two spectra: UVA and UVB. UVB radiation causes sunburns and certain types of cancers such as basal cell and squamous cell carcinoma, while UVA radiation causes melanoma skin cancer and premature aging.

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    How is the atmosphere heated?

    A:

    The atmosphere derives heat from the sun, which emits radioactive waves towards it. This heat then spreads throughout the atmosphere via radiation, convection and conduction.

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    How do you calculate the dew point?

    A:

    To calculate dew point, you need to know the current temperature and relative humidity, and then solve the equation Td = T - ((100 - RH) / 5) for Td, which stands for the dew point temperature in degrees Celsius. This equation is accurate for humidity values above 50 percent.

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    How much oxygen is in the air?

    A:

    Since the atmosphere has a mass of approximately 5.15 x 10^18 kilograms, the total mass of oxygen in the atmosphere is approximately 1.08 x 10^18 kilograms. Oxygen makes up approximately 20.9 percent of the Earth's atmosphere.

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    What atmospheric layer contains the most ozone?

    A:

    The ozone layer contains about 90 percent of Earth's ozone. It is part of Earth's stratosphere and lies between 6 and 30 miles above the planet's surface, according to the Environmental Protection Agency. The highest concentration of ozone is found between 12 and 19 miles above the surface, notes Wikipedia.

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