UPSC Environment and Ecology – Chapter 21: Ozone Depletion, Acid Rain and Atmospheric Issues (25 MCQs)

← Back

UPSC Environment and Ecology – Chapter 21: Ozone Depletion, Acid Rain and Atmospheric Issues (25 MCQs) – 24 questions, subject: Environment. Every question has the correct answer with a one-line explanation; tap "Show Answer". Free practice for TNPSC, UPSC, SSC, Bank and RRB exams – Shanmugam IAS Academy, Coimbatore.

Get daily current affairs & exam alerts – follow us YouTube WhatsApp Channel Telegram Channel Facebook Page Instagram
Share with friends & study groups
Link to this page from your website / blog (HTML code)
1.  

Most of the Earth's ozone is found in the:

Correct Answer: D [stratosphere]

Explanation:

The ozone layer lies in the stratosphere, mostly between 15 and 35 km, where it absorbs the Sun's harmful UV-B radiation.

2.  

An "ozone hole" refers to total column ozone below about:

Correct Answer: B [220 DU]

Explanation:

An ozone hole is an area where total column ozone falls below 220 Dobson units, against a global average of about 300 DU.

3.  

The Montreal Protocol was adopted in:

Correct Answer: C [1987]

Explanation:

The Montreal Protocol was adopted on 16 September 1987 and entered into force on 1 January 1989.

4.  

Halons, which are controlled under the Montreal Protocol as ozone-depleting substances, were mainly used in:

Correct Answer: B [fire extinguishers]

Explanation:

halons were used in fire extinguishers; they release bromine, which destroys stratospheric ozone.

5.  

Under the Kigali Amendment, India must freeze HFC use in:

Correct Answer: B [2028]

Explanation:

India is in Article 5 Group 2, which uses 2024–2026 as baseline years and freezes HFC consumption in 2028.

6.  

The Multilateral Fund under the Montreal Protocol was created by the:

Correct Answer: A [London Amendment, 1990]

Explanation:

The 1990 London Amendment set up the Multilateral Fund to help developing countries meet their phase-out obligations.

7.  

The Antarctic ozone hole is largest during:

Correct Answer: C [September–October]

Explanation:

southern spring.

8.  

According to the 2022 UNEP–WMO assessment, the Antarctic ozone layer is expected to recover to 1980 values by about:

Correct Answer: A [2066]

Explanation:

The 2022 UNEP–WMO assessment projects Antarctic ozone returning to 1980 values around 2066, later than the Arctic (2045) and elsewhere (2040).

9.  

Natural rain is slightly acidic with a pH of about:

Correct Answer: B [5.6]

Explanation:

Rain dissolves atmospheric carbon dioxide, forming weak carbonic acid, so unpolluted rain has a pH of about 5.6.

10.  

Assertion (A): The ozone hole forms mainly over Antarctica.

Reason (R): Extremely cold polar stratospheric clouds there speed up the release of active chlorine.

Correct Answer: A [Both A and R are true, and R is the correct explanation of A]

Explanation:

Polar stratospheric clouds form only in intense Antarctic cold; reactions on them release active chlorine that destroys ozone when spring sunlight returns.

11.  

The Malé Declaration (1998) on control and prevention of air pollution and its likely transboundary effects relates to:

Correct Answer: C [South Asia]

Explanation:

Adopted at Malé in April 1998 at SACEP's Governing Council, it addresses air pollution and its transboundary effects in South Asia.

12.  

The "marble cancer" of the Taj Mahal is associated with:

Correct Answer: A [acid rain]

Explanation:

Acids formed from sulphur and nitrogen oxides attack the calcium carbonate of marble, corroding and discolouring the Taj Mahal – 'marble cancer'.

13.  

India's Ozone Depleting Substances (Regulation and Control) Rules were notified in:

Correct Answer: D [2000]

Explanation:

India notified the Ozone Depleting Substances (Regulation and Control) Rules in 2000 under the Environment (Protection) Act.

14.  

The India Cooling Action Plan (2019) aims to reduce refrigerant demand by:

Correct Answer: C [25–30 per cent]

Explanation:

ICAP (2019) targets a 25–30 per cent cut in refrigerant demand by 2037-38, besides lower cooling demand and energy needs.

15.  

The first regional treaty on acid rain was the:

Correct Answer: B [Convention on Long-Range Transboundary Air Pollution]

Explanation:

1979.

16.  

Arrange in chronological order:

1. Montreal Protocol adopted
2. London smog
3. Kigali Amendment adopted
4. India Cooling Action Plan released

Select the correct order:

Correct Answer: C [2-1-3-4]

Explanation:

1952, 1987, 2016, 2019.

17.  

Which of the following is used as a fumigant and is controlled under the Montreal Protocol?

Correct Answer: D [Methyl bromide]

Explanation:

Methyl bromide, a soil and quarantine fumigant, releases bromine that destroys ozone, so it is controlled under the Montreal Protocol.

18.  

Classical (London-type) smog is made mainly of:

Correct Answer: D [smoke and sulphur dioxide]

Explanation:

London-type smog forms in cold, damp weather from coal smoke and sulphur dioxide, as in the London smog of 1952.

19.  

Consider the following about HFCs:

1. They do not deplete the ozone layer.
2. They are powerful greenhouse gases.
3. They are being phased out under the Vienna Convention.

Which of the statements given above are correct?

Correct Answer: B [1 and 2 only]

Explanation:

HFCs contain no chlorine or bromine, so they spare ozone, but they are potent greenhouse gases phased down under the Kigali Amendment.

20.  
UPSC Prelims 2024

Consider the following statements:

Statement- I: Thickness of the troposphere at the equator is much greater as compared to poles.

Statement-II: At the equator heat is transported to great heights by strong convection currents.

Which one of the following is correct in respect of the above statements?

Correct Answer: A [Both Statement-I and Statement-II are correct and Statement-II explains Statement-I]

Explanation:

Strong equatorial convection lifts heat to great heights, so the troposphere reaches about 18 km at the equator against about 8 km at the poles.

21.  
UPSC Prelims 2023

Consider the following:

1. Aerosols
2. Foam agents
3. Fire retardants
4. Lubricants

In the making of how many of the above are hydrofluorocarbons used?

Correct Answer: C [Only three]

Explanation:

HFCs are used in aerosols, foam-blowing agents and fire retardants, but not in lubricants.

22.  
UPSC Prelims 2022

Consider the following :

1. Carbon monoxide
2. Nitrogen oxide
3. Ozone
4. Sulphur dioxide

Excess of which of the above in the environment is/are cause(s) of acid rain ?

Correct Answer: B [2 and 4 only]

Explanation:

Nitrogen oxides and sulphur dioxide react with water and oxygen to form nitric and sulphuric acids, which cause acid rain.

23.  
UPSC Prelims 2015

Which one of the following is associated with the issue of control and phasing out of the use of ozone-depleting substances?

Correct Answer: B [Montreal Protocol]

Explanation:

The Montreal Protocol (1987) sets a time-bound phase-out of CFCs, halons and other ozone-depleting substances.

24.  
UPSC Prelims 2013

Acid rain is caused by the pollution of environment by

Correct Answer: D [nitrous oxide and sulphur dioxide]

Explanation:

Only option (d) contains the acid-rain gases – an oxide of nitrogen and sulphur dioxide, which form nitric and sulphuric acids.

➤ Full notes, maps, tables, a reason for every option and Mains PYQs – U18 · Environment and Ecology (UPSC book, ₹249): www.shanmugamiasacademy.in/study-materials/upsc-environment-ecology

📘 U18 · Environment, Ecology, Biodiversity and Climate Change – UPSC Civil Services (Prelims & Mains)
Here you get the answer with a one-line explanation. 24 chapters · 701 MCQs incl. UPSC Prelims PYQs with a reason for every option · 120 Mains questions + Mains PYQs · maps, tables, revision cards
Get the book – ₹249 ₹499 →
Score: 0 Answered: 0 / 0