1. THE OZONE HOLE

2. The ozone hole is the general thinning of the ozone layer in the stratosphere, which occurs mainly in the spring, over the polar regions. The decrease, that has begun to study from 1979, can be up to 70% in the Antarctic and 40% in the area of the Arctic. WHAT IS THE OZONE HOLE?

3. The reduction occurs mainly by catalytic destruction of halogenated compounds that reach the stratosphere.The ozone layer (O3) is used as a filter for ultraviolet radiation, in fact it absorbs for all their component UV-C. Then the dose of UV-B radiation that reaches the earth's surface depends inversely on the ozone concentration in the upper atmosphere. WHAT ARE THE CAUSES?

4. WHAT ARE THE CONSEQUENCES? The UV-B radiation possess a sterilizing effect for many forms of life: are harmful for the eyes; for the skin, because can trigger the formation of melanomas and other cancer; it cause a partial inhibition of photosynthesis in plants, with consequent risk of lowering ability to eat from the whole ecosystem, including reduction of crops, and destroy important fractions of phytoplankton that it is the base of the marine food chain.

5. To limit the damage we can eliminate from the market the chlorofluorocarbons which are the main suppliers of the destructive element, and replace them with some similar element and less dangerous. WHAT WE CAN DO?

6. ILARIA NATALE2° dA.S. 2013/2014