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

Multiple choice general knowledge

Radiocarbon is produced in the atmosphere as a result of

  1. collision between fast neutrons and nitrogen nuclei present in the atmosphere

  2. action of ultraviolet light from the sun on atmospheric oxygen

  3. action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere

  4. lightning discharge in atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Radiocarbon (carbon-14) is produced in the upper atmosphere when cosmic ray neutrons collide with nitrogen-14 nuclei, causing a nuclear reaction that converts nitrogen-14 to carbon-14. This is a well-documented nuclear physics process. The other options incorrectly attribute it to UV light, solar radiation on CO2, or lightning.

Multiple choice general knowledge science & technology

Which of the following is/are true about Ozone layer?

  1. Ozone layer is a concentration of ozone molecules up in the Stratosphere (10 to 50 kms)

  2. Ozone is produced only at the ground level and flows to high altitude to form Ozone layer

  3. In Stratosphere Ultraviolet rays break down oxygen molecules into atomic oxygen(O) which then combines with Oxygen molecule(O2) to form Ozone (O3)

  4. Around 90% of the Ozone in our atmosphere is contained in Troposphere only (within 10 kms)
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

The ozone layer (90% of atmospheric ozone) is in the stratosphere (10-50 km), formed when UV radiation splits oxygen molecules into atomic oxygen which then combines with O2 to form O3. Ozone is NOT produced only at ground level, and 90% is NOT in the troposphere. This process is fundamental atmospheric chemistry.

Multiple choice general knowledge science & technology

Which one of the following is used to measure ozone level in the atmosphere?

  1. By the number of ozone atoms in an atmospheric column, called Chapman unit

  2. By expressing the columnar density of Ozone in Dobson unit (thickness of ozone in an atmospheric column under standard temperature and pressure)

  3. By measuring the ultraviolet radiation level in the ground

  4. By measuring the Oxygen level in the Stratosphere
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ozone levels are measured in Dobson Units (DU), representing the thickness of the ozone layer in a column compressed to standard temperature and pressure. 300 DU = 3mm thick layer. Chapman unit is not used for ozone measurement. Ground UV or oxygen measurements don't directly quantify ozone. This is standard atmospheric science.

Multiple choice general knowledge science & technology

One of the following does NOT cause depletion in Ozone layer. Which one is it?

  1. Human activities of using CFC, HCFC within air-conditioners or refrigerators

  2. Man-made climate change leading to unusual reduction in stratospheric temperature (while temperature nearer earth increases)

  3. Dumping of old refrigerators in the ground

  4. Volcanic eruptions leading to injection of hydrogen chloride (HCl) into the atmosphere
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

CFCs/HCFCs from refrigeration and climate change affecting stratospheric temperatures both cause ozone depletion. Dumping old refrigerators releases CFCs. Volcanic HCl DOES cause depletion but the question asks what does NOT cause depletion - this is a double negative trick question. All options except volcanic eruptions are anthropogenic, but volcanoes ARE natural ozone-depleting agents.

Multiple choice general knowledge science & technology

It is known that if Ozone layer is depleted, ultraviolet rays, especially UV-B reaches the ground. Which one of the following is NOT an impact of Ozone depletion?

  1. Human health is severely impacted with impacts such as Skin Cancer, cataracts and damage to immune systems

  2. Phytoplankton production is reduced leading to severe impact on marine ecosystems

  3. Ozone depletion directly leads to natural calamities such as storms, floods etc

  4. By severely damaging plants and other sinks of greenhouse gases, ozone depletion leads to climate change
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ozone depletion increases UV-B reaching earth, causing skin cancer, cataracts, immune damage (A), reduces phytoplankton (B), and damages plants worsening climate change (D). However, it does NOT directly cause storms/floods - those are separate climate phenomena. This tests understanding of ozone depletion's actual impacts versus speculative effects.

Multiple choice general knowledge science & technology

It is said that 'Ozone is good up high but bad nearby'. In this context which one of the following is INCORRECT?

  1. Ozone in stratosphere protects us from damaging ultraviolet rays & hence good for us

  2. Ozone in ground level worsens bronchitis or asthma & hence bad for us

  3. Ozone in high-altitude creates a favourable air movement leading to easy air travel

  4. Emissions of NOX from industries or motor vehicles creates ozone in the ground level through chemical reactions
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

'Ozone is good up high but bad nearby' correctly states that stratospheric ozone protects from UV (A), while ground-level ozone from NOx emissions worsens respiratory diseases (B, D). Option C is INCORRECT because high-altitude ozone does NOT create favorable air movement for travel - it absorbs UV, affecting atmospheric circulation but not specifically 'air travel'. This tests which statement doesn't fit the science.

Multiple choice general knowledge science & technology

Mirage is due to

  1. unequal heating of different parts of the atmosphere

  2. magnetic disturbances in the atmosphere

  3. depletion of ozone layer in the atmosphere

  4. equal heating of different parts of the atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mirage is an optical illusion caused by atmospheric refraction - light bends when passing through air layers of different temperatures due to unequal heating. This makes distant objects appear displaced, creating the illusion of water reflections.

Multiple choice general knowledge science & technology

What is the name of the layer of earth’s atmosphere that absorbs the majority of the potentially damaging ultraviolet light from the sun?

  1. Ultravoilet Layer

  2. Infrared Layer

  3. GreenHouse Layer

  4. Ozone Layer
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The ozone layer in the stratosphere contains high concentrations of ozone (O3) molecules that absorb harmful UV-B and UV-C radiation from the sun, protecting life on Earth. The infrared, greenhouse, and ultraviolet layers are not actual atmospheric layers.

Multiple choice general knowledge science & technology

Ozone hole refers to

  1. hole in ozone layer

  2. decrease in the ozone layer in troposphere

  3. decrease in thickness of ozone layer in stratosphere

  4. increase in the thickness of ozone layer in troposphere
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ozone hole refers to the thinning of the ozone layer in the stratosphere, particularly over Antarctica. It is not an actual hole but a decrease in thickness of the ozone layer in the stratosphere. Option C is correct.

Multiple choice general knowledge science & technology

Radiocarbon is produced in the atmosphere as a result of

  1. collision between fast neutrons and nitrogen nuclei present in the atmosphere

  2. action of ultraviolet light from the sun on atmospheric oxygen

  3. action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere

  4. lightning discharge in atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Carbon-14 (radiocarbon) forms when cosmic ray neutrons collide with nitrogen-14 atoms in the upper atmosphere, transmuting them into radioactive carbon-14. This continuous production maintains the steady-state concentration of radiocarbon used in radiometric dating.

Multiple choice general knowledge science & technology

Mirage is due to

  1. unequal heating of different parts of the atmosphere

  2. magnetic disturbances in the atmosphere

  3. depletion of ozone layer in the atmosphere

  4. equal heating of different parts of the atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mirages occur when ground heat creates a temperature gradient in the air, with hot, less dense air near the surface and cooler air above. Light rays refract (bend) as they pass through these layers of different densities, creating distorted or displaced images of distant objects.

Multiple choice

Communication satellites are located in which of the following atmospheric layers?

  1. Exosphere

  2. Stratosphere

  3. Ionoshere

  4. Troposphere

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Satellites are in the exosphere layer of the atmosphere. This is the layer where our atmosphere merges with space. The ionosphere is defined as the layer of the Earth's atmosphere that is ionized. The ionosphere represents less than 0.1% of the total mass of the Earth's atmosphere. Even though it is such a small part, it is extremely important.

Multiple choice

Which word in the passage is a synonym of 'deadly'?

Directions: Read the following passage to answer the given question.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.

The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

  1. Shielded

  2. Lethal

  3. Vital

  4. Active
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 Deadly means something/someone extremely dangerous. 

Multiple choice

The greatest threat to the ozone layer is from

Directions: Read the following passage to answer the given question.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.

The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

  1. chlorofluorocarbons

  2. UV–B rays

  3. O3 molecules

  4. foamed plastic products
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 See last two sentences of paragraph three.