The word Ozone is derived from Greek Ozein meaning "to smell". The atmosphere may be divided into two parts based on regions of concentrations of Ozone region below and the ion region above. Ozone is formed dissociation of molecular oxygen and the combining of atomic oxygen with molecular oxygen. The optimum conditions are found at an elevation of 30 km (20 miles) where we find the maximum concentrations of the Ozone layer. This ozone layer in the stratosphere acts as an umbrella that shields life from harmful ultraviolet radiation from the Sun by absorbing most of the short wavelengths of this radiation. The portion of the uv radiation that gets through the ozone layer burns and tans our skin and may cause skin cancer. Holes have recently been found in this layer. For more details of the causes, click below.
Ozonosphere extends up to a height of 70 km (45 miles)
Ozone is unstable in the presence of sunlight, and it dissociates again into atomic and molecular oxygen. There is little ozone present naturally near the Earth's surface. It can be formed by electrical sparking discharges, and by Photochemical reactions to air pollutants giving rise to photochemical smog. For more on photochemical smog, click below:
The ionosphere lies above the ozone layer, above 70 km (45 miles). Electrically charged ions and electrons are trapped in the Earth's upper regions. Variations in the ion density give rise to three regions or layers -- D, E, and F. The D layer strongly absorbs radio waves below a certain frequency. Radio waves with frequencies above this value pass through D layer, but are reflected by E and F layers. Thus the ionosphere provides global radio communications by the reflection of the radio waves. For more information, click below.
Solar disturbances, which produce a shower of incoming energetic particles , are also associated with beautiful displays of lights. The Northern lights are called Aurora borealis (Latin aurora "dawn", and boreas "northern wind"). South lights are called aurora australis (Latin auster "southern wind"). Ions and electrons trapped in the Earth's magnetic field are deflected towards the magnetic poles, causing the lights.
For more information and spectacular photographs, click below:
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