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प्रश्न
Is ozone depletion related to global warming?
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उत्तर
Ozone depletion and global warming are separate problems, though some agents contribute to both. Chlorofluorocarbons (CFCs) are the principle cause of ozone depletion, but they also happen to be potent heat-trapping gases. Still, CFCs are responsible for less than 10 per cent of total atmospheric warming, far less than the 63 percent contribution of carbon dioxide. Thus, attention paid to CFCs has been on their ozone depletion role. This will change as CFCs are phased out and replaced by hydro chlorofluorocarbons (HCFCs) and hydro fluorocarbons (HFCs such as R-134a). These chemicals have little or no effect on the ozone layer but are strong heat-trapping gases. As their concentration in the atmosphere is already rising, the likely net effect in the future is that reductions in the CFC-related contribution to global warming will be offset by the presence of HCFCs and HFCs
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संबंधित प्रश्न
What would happen if the ozone layer in the atmosphere completely disappears?
Which pollutant released into the air during refrigeration and airconditioning is the greatest contributor to the depletion of ozone layer?
(a) BHC
(b) DDT
(c) CFC
(d) UNEP
The depletion of ozone layer in the upper atmosphere is mainly due to the emission of :
(a) unburnt hydrocarbons
(b) chlorofluorocarbons
(c) greenhouse gases
(d) ultraviolet radiations
The excessive exposure of humans to ultraviolet rays results in:
- damage to immune system
- damage to lungs
- skin cancer
- peptic ulcers
The gas A is used by most of the animals to obtain energy from food by the process of respiration. When A is acted upon by radiation X, it gets converted into another gas B which is an allotrope of A but poisonous when inhaled. B forms a kind of layer C in the upper atmosphere which absorbs radiations X coming from a source Y and prevent them from reaching the earth. Some chemicals Z released from the various devices on the earth are destroying the layer C slowly. In fact, a hole has already been formed in layer C over the area D of the earth.
(a) What are gases (i) A, and (ii) B? Write their molecular formulae.
(b) Name the layer C.
(c) What are (i) X, (ii) Y, and (iii) Z?
(d) Name the area D.
(e) Name any two human ailments which may be caused by X.
State the chemicals responsible for ozone layer destruction.
How is ozone formed in the upper atmosphere? State its importance. What is responsible for its depletion? Write one harmful effect of ozone depletion.
Give reason for the following:
The formation of ozone involves a chemical reaction called photolysis.
Gas A, found in the upper layers of the atmosphere, is a deadly poison but is essential for all living beings. The amount of this gas started declining sharply in the 1980s.
- Identify Gas A. How is it formed at higher levels of the atmosphere?
- Why is it essential for all living beings? State the cause for the depletion of this gas.
World Ozone day is celebrated on ______.
