Environmental Studies · Geography
Atmospheric Structure and Ozone
1,401 Questions
Atmospheric structure and ozone layer topics examine the Earth's atmospheric layers, the impact of solar radiation, and ozone depletion mechanisms. These environmental science concepts are crucial for general awareness sections in multiple competitive examinations. Review these questions to solidify your understanding of the stratosphere, polar vortex effects, and greenhouse gases.
Earth's atmospheric layersOzone layer depletionSolar ultraviolet radiationPolar vortex effectsCarbon dioxide impactOzone-depleting substances
Atmospheric Structure and Ozone Questions
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Stratosphere
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Troposphere
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Mesosphere
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None of these
A
Correct answer
Explanation
The stratosphere contains approximately 90% of the atmosphere's ozone, concentrated in the ozone layer at 15-35 km altitude. This ozone absorbs harmful UV radiation, which is why temperature increases with altitude in this layer.
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Low humidity
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High humidity
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High rainfall
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None of these
A
Correct answer
Explanation
The stratosphere is extremely dry because it sits above the tropopause, which acts as a barrier preventing significant water vapor from the troposphere below (where most weather and clouds occur) from rising into the stratosphere.
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Troposphere
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Mesosphere
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Thermosphere
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None of these
C
Correct answer
Explanation
In the thermosphere, temperature increases dramatically with altitude because the extremely thin air absorbs intense solar and cosmic radiation. Despite high kinetic temperatures, the low density means it would feel extremely cold to a human due to minimal heat transfer.
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Lithosphere
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Mesosphere
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Thermosphere
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Hydrosphere
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Stratosphere
A
Correct answer
Explanation
The outer solid layer of the earth, called the lithosphere, is made of rock. The lithosphere is the solid outermost shell of a rocky planet. On the Earth, the lithosphere includes the crust and the uppermost layer of the mantle.
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Most of the sun-s rays will be reflected back
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The harmful sun-s rays will reach the earth?s surface
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The temperature of earth will increase
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The concentration of chlorofluorocarbons will increase in the atmosphere
B
Correct answer
Explanation
The ozone layer filters harmful UV radiation. Its depletion allows more UV-B and UV-C rays to reach Earth's surface, increasing skin cancer risk and ecosystem damage.
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Australia
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Asia
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Europe
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Antarctica
D
Correct answer
Explanation
The Antarctic ozone hole was discovered in the 1980s and is most severe during Antarctic spring (September-October). Cold conditions and CFC accumulation create this seasonal phenomenon.
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water balance in nature
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warm temperature of the earth
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carbon cycle in nature
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ozone layer over the atmosphere
B
Correct answer
Explanation
The greenhouse effect traps heat in Earth's atmosphere, maintaining average temperatures around 15°C instead of -18°C. Without it, Earth would be too cold for life as we know it.
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air pollution
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sun's harmful rays
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solar heat
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sudden climatic changes
B
Correct answer
Explanation
The ozone layer absorbs harmful ultraviolet (UV) radiation from the sun, protecting living organisms from DNA damage and skin cancer. It does not filter general air pollution or moderate solar heat - its primary function is blocking UV rays.
B
Correct answer
Explanation
Earth's atmosphere contains approximately 21% oxygen, which is essential for most life forms and combustion. The remaining 78% is mostly nitrogen, with trace gases making up the final 1%. This 21% figure is a fundamental fact in atmospheric science.
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Chlorofluorocarbons
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Oxides
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Sulphides
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Hydroxides
A
Correct answer
Explanation
Chlorofluorocarbons (CFCs) are synthetic compounds that break down in the stratosphere, releasing chlorine atoms that catalytically destroy ozone molecules. This led to the formation of the ozone hole. Oxides, sulphides, and hydroxides do not have this ozone-depleting effect.
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CFC's displace the ozone layer
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CFC's absorb the ozone gas
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CFC's react with the ozone gas
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CFC's cover the ozone layer
C
Correct answer
Explanation
CFCs release chlorine atoms when exposed to UV radiation in the stratosphere. These chlorine atoms react with ozone (O3), breaking it down into O2. One chlorine atom can destroy thousands of ozone molecules through a chain reaction.
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Ozone is a mono-atomic form of oxygen
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Ozone is a poisonous gas
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Ozone is present in the lower atmosphere
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Ozone reflects the sun's rays
B
Correct answer
Explanation
Ozone is indeed a poisonous/toxic gas that can cause respiratory damage. It is triatomic (O3), not mono-atomic. It is found in the stratosphere (upper atmosphere), not the lower atmosphere, and it absorbs UV radiation rather than reflecting it.
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I.R
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U.V
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Visible
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Both (A) and (B)
B
Correct answer
Explanation
The ozone layer primarily absorbs ultraviolet (UV) radiation from the sun. This absorption protects living organisms from harmful UV rays that can cause skin damage and cancer.
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Ultra-violet ray
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Dust
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Infra red rays
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White light
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Air pollution
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Earth's gravity
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Ozone layer
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Atmospheric pressure
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Solar radiation
B
Correct answer
Explanation
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity.