ozone depletion

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OZONE DEPLETION

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Page 1: Ozone depletion

OZONE DEPLETION

Page 2: Ozone depletion

OZONE DEPLETION

Ozone layer present in the stratosphere of the atmosphere acts as a protective shield for earth against harmful UV radiation.

Ozone is a colorless gas, depletion of ozone leads to formation of holes in its shield and owing to this harmful UV rays would reach the earth.

Page 3: Ozone depletion

OZONE DEPLETION

Harmful Effects – These rays have varying effects on earths surface, on living beings, on ecosystem.

Though, most of the plants and animals have some kind of protective mechanisms from UV, a longer exposure to these radiations can penetrate the lower layers of body, leading to skin cancer and damage to eyes in humans.

In plants, the complete process of photosynthesis, is affected. The rays can penetrate the surface of oceans, which can destroy the

entire marine life and entire food chain is affected. Small plants and animals living in sea get killed by these radiations.

In the southern part of chile, as a result of low levels of ozone, people suffered severe burns of skin, cattle became blind, trees wilted and some animals died.

Page 4: Ozone depletion

OZONE DEPLETION

Sherwood Rowland, university of california found that CFCs are the substances that destroy the ozone layer, CFCs can remain intact for years, CFCs are a whole family of chemicals that contain chlorine and fluroine.

A single chlorine molecule can break up thousands of molecules of ozone.

Another family of compound, called Halons, which contain bromine is another major substance that can destroy ozone.

Page 5: Ozone depletion

Montreal Protocol

Depletion of ozone layer became a great concern worldwide. In 1987, 24 countries and by 1990 most of the nations signed Montreal protocol agreement, committing themselves to phase out the production and consumption of ozone depleting substances.

Developing countries were given a grace period of extra 10 years. India and China were hesitant to sign the protocol as these nations with huge population and their eagerness to modernization were creating a growing demand for appliances and consumer products.

Page 6: Ozone depletion

Montreal Protocol

As a matter of this, quotas of production and consumption was given considering historical emissions, which would automatically restrict developed countries from taking advantage.

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