1. THE OZONE LAYER

2. In atmosphere there are natural concentrations of greenhouse gases
In atmosphere there are natural concentrations of greenhouse gases. Short wavelength rays and the visible light of the sun can cross these gases, warming the atmosphere, the oceans, the surface of the planet and the living organisms.
The ozone layer acts like a protective shield that filters ultraviolet-B radiation, UV radiation having other wavelengths than those that lead to ozone formation.

3. What’s the ozone?
Ozone is a particular molecule of oxygen containing three atoms of oxygen (O3). It is formed in a few million years by the action of sunlight on oxygen.
The ozone looks like a layer situated at altitudes between 19 to 30 km. If all the ozone was concentrated in a pure form, the land would be surrounded by a layer of only 3 mm.

4. Ultraviolet rays hit oxygen molecule
How the ozone is being formed?
Ultraviolet rays hit oxygen molecule
… the oxygen molecule breaks in two atoms
Free hydrogen atoms collide with oxygen molecules ...
... and forms ozone molecules

5. Protects all life on Earth by totally retaining UV
Why it is so important?
Protects all life on Earth by totally retaining UV
Adjusts the temperature of the stratosphere.

6. The causes of ozone depletion
Scientific evidence indicates that stratospheric ozone is being destroyed by a group of manufactured chemicals, the chlorofluorocarbons (also called CFCs) and other industrial chemicals. These products are still used in air conditioners, cosmetic products, liquids in pressurized steel bottles (sprays) and as refrigerant of the refrigerators.
Freons were removed from industrial processes and have been replaced by other substances.

7. The effects of ozone depletion
diminished crop caused by the size reduction of plant leaves;
marine life and plankton destruction;
reduced efficacy of the immune system;
severe burns of sun exposed areas

8. Ozone depletion was reported in 1985 by scientists working in Antarctica, when they observed the formation of a hole in the ozone layer.
In 1995, it was observed that in the Arctic and Northern European area holes in the ozone layer were formed.

9. The evolution of the hole in the ozone layer
The ozone layer began to deteriorate by growing the amount of harmful gases produced at land surface. Once in atmosphere they caused substantial disruption in the ozone layer.

10. Due to ozone we still enjoy every sunrise, every rainbow, springs, summers, autumns, winters, life in general ...

11. Seen from the Space, the Earth looks so healthy, but…..
We must not forget that our health and the future of the planet depend on us, on our degree of direct or indirect involvement, on our behaviors regarding environmental issues.

12. On December 19, 1994, the United Nations General Assembly proclaimed September 16 the International Day for the Preservation of the Ozone Layer.