From a distance Space, Planet Earth looks like a beautiful blue sphere. The special colour and beauty ‘Nature’ arises from the vast greeneries of forest, vegetation and life found on Earth. The apparent abundance of this life-giving source depends on the thickness of the life protecting ‘Ozone Layer’ surrounding the ‘Planet Earth’ and safe guards life on this planet.
The umbrella of ozone layer absorbs the harmful ultraviolet radiation emitting from the Sun and facilitate life giving source of Solar energy to the planet Earth. But over the past half-century, humans have placed the Ozone Layer in jeopardy.
Un-knowingly humans have released into atmosphere, chemicals that are destroying part of the ozone layer and thus upsetting the delicate balance established by the nature. Thickness of ozone layer is not a fixed quantity. It fluctuates in time and space. That’s why we need basic ‘data’. According to Muhammad Anees Siddiqui, a meteorologist at the Pakistan Meteorological Department, Quetta, ‘It is believed that Ozone layer depletion problem can be alleviated if public have awareness and good knowledge about their natural environment.’
About 90% of Ozone is found in layer surrounding the Earth’s atmosphere between approximately 10 and 50 kilometers i.e. about 6 to 30 miles above the Earth’s surface.
The ozone layer is essential to life on earth, as it absorbs harmful ultraviolet-B radiation from the sun. In recent years the thickness of this layer has been decreasing, leading in extreme cases to holes in the layer. Natural phenomena, such as sun-spots and stratospheric winds, also decrease stratospheric ozone levels, but typically not by more than 1-2%.
The main potential consequences of this ozone depletion are: increase in UV-B radiation at ground level: Continuous exposure to UV radiation affects humans, animals and plants, and can lead to skin problems (ageing, cancer), depression of the immune system, and corneal cataracts (an eye disease that often leads to blindness). Increased UV radiation may also lead to a massive die-off of photoplancton (a CO 2 ‘sink’) and therefore to increased global warming. Disturbance of the thermal structure of the atmosphere, probably resulting in changes in atmospheric circulation; Reduction of the ozone greenhouse effect: ozone is considered to be a greenhouse gas. A depleted ozone layer may partially dampen the greenhouse effect. Therefore efforts to tackle ozone depletion may result in increased global warming. Changes in the tropospheric ozone and in the oxidising capacity of the troposphere.
The ‘Ozone hole’ is a region of atmosphere over Antarctica from which “total ozone” has extremely decreased. Every year, the hole appears in August (austral spring) and develops during September / early October; after that, it declines gradually, and finally vanishes during the end of November and December (austral summer).
The Ozone hole is born, through absorption of solar radiation toward summer, the polar night vortex gradually warms up from its inside and therefore weakens, finally dissipating completely; exchange of air begins between inside of the vortex and outside, then the Ozone hole disappears. The Ozone poor air, on this occasion, diffuses away from Antarctica and reduces Ozone layer of the Southern Hemisphere surrounding the Antarctic.
It has been predicted that the hole in the ozone layer in the coming years will probably be slightly smaller than the all-time largest of 2003, signaling that depletion is still occurring but possibly at a slower rate, a U.N. agency said.
“The size of this year’s ozone hole is approaching an all-time high, but it will probably not break any records,” said Geir Braathen, an ozone specialist at the World Meteorological Organization, told The Associated Press.
Yet it is our duty as the responsible youth of today, to spread awareness in this regard. We should conduct serious seminars and workshops to spread awareness. People should be aware that what kind of substances are causing the ozone hole and they should avoid those chemical products to conserve the ozone layer.
