ozone layer

 ozone layer:

Ozone the stratospheric ozone layer is normal part in the earth atmosphere that absorbs High-frequency ultraviolet rays and protects us form their damaging effects. In contrast ground level ozone is an air pollutants, which has harmful respiratory and cardiovascular effect. Ground level is largely the result of UV photosynthesis of NOx and VOCs.( Product of vehicular and industrial combination).

the ozone layer or ozone shield is a region of the upper atmosphere between roughly above earth surface containing relatively High concentration of ozone molecule (O3). The ozone layer form a thin shield in the upper atmosphere protecting life on earth from UV rays. Ozone is a naturally occurring gas that is found in two layer of the atmosphere.In the layer surrounding the earth surface the troposphere ground level and bad ozone is an air atmosphere to urban smog. The troposphere extends up to the stratosphere which good ozone protect life on earth by absorbing the sun rays. Stratospheric ozone is most concentrated between 6 or 30 mile aboves the earth surface.

Ozone is form of molecular oxygen existing predominantly in the upper atmosphere. It is continuously formed by oxygen absorbing the sun short wave UVC and the broken down by a number of chemical such as chlorine form chlorofluorocarbons.

ozone layer effects 

Ozone layer depletion increase the amount of UVB that reaches the earth  surface. Laboratory and epidemiological studies demonstrate that UVB cases non- melanoma skin cancer and Play a major role in malignant melanoma development of cataract a clouding of the eye lens.

Changes to our ozone layer over the past 40 year have affected levels of UV radiation and therefore the risk of peoples developing skin cancer, an international study has found. Some 2,000 Australians die of skin cancer every year with Australia having one of the highest rate of the disease in the world.

The study examined changes to the ozone layer and the impact on UV radiation and change in climate. One of the lead author Professor Robyn Lucas from The Australian National University, said the study highlight the harm associated with increased exposure to high levels of UV radiation. "It puts peoples at greater risk of developing skin cancer and other diseases," Professor Lucas said.

"Increased rate of skin cancer over the past 100 years show how susceptible some human population would be to uncontrolled ozone depletion." 

 example we know exposure to UV radiation account for up to 95 percents of the risk of developing certain types of melanoma in light-skinned populations.

While melanoma accounts for less than five per cent of cancer it has a particularly high mortality rate, with around 60,000 deaths world wide each year. The study show these numbers would have been much worse, if the Montreal Protocol had not been implemented by the UN in 2008.

The Montreal Protocol treaty led to the phasing out of the use of man-made substance that deplete the ozone layer, primarily chlorofluorocarbons (CFCs) that were used in refrigeration and as the propellant in aerosols.