Ozone & Protocols — Set 4
Environment · ओज़ोन और प्रोटोकॉल · Questions 31–40 of 50
World Ozone Day is celebrated annually on which date to mark the signing of the Montreal Protocol?
Correct Answer: D. September 16
September 16 was designated as the International Day for the Preservation of the Ozone Layer by the UN General Assembly. It commemorates the day the Montreal Protocol was opened for signature in 1987. It aims to spread awareness about the progress and challenges in ozone protection.
Which of the following is the most significant man-made source of ozone-depleting substances?
Correct Answer: B. Refrigeration and Air Conditioning
Refrigeration systems used CFCs and HCFCs as coolants for decades. These chemicals often leak into the atmosphere during equipment disposal or maintenance. The transition to non-ozone-depleting refrigerants is a core goal of environmental protocols.
The 'Ozone Layer' is located within which part of the Earth's atmosphere?
Correct Answer: B. Stratosphere
The stratosphere is the layer above the troposphere, extending from about 10 to 50 kilometers. It is characterized by an increase in temperature with altitude due to ozone absorbing solar energy. This layer protects the Earth from the sun's high-energy ultraviolet radiation.
What does the 'Montreal Protocol' regulate?
Correct Answer: B. Ozone Depleting Substances (ODS)
The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of various ODS. It lists nearly 100 chemicals that must be gradually reduced and eliminated. It is considered a model for successful international environmental policy.
Which of these is a greenhouse gas that also contributes to ozone depletion, though it is not a CFC?
Correct Answer: A. Nitrous Oxide
Nitrous Oxide is now the leading ozone-depleting substance being emitted by human activities. It is largely produced through agricultural practices and industrial processes. Unlike CFCs, it is not yet strictly regulated by the Montreal Protocol.
The discovery of the 'Ozone Hole' in 1985 was first reported by scientists from which country?
Correct Answer: B. United Kingdom
The correct answer is 'United Kingdom'. British Antarctic Survey scientists Joseph Farman, Brian Gardiner, and Jonathan Shanklin published their findings in 1985. They noticed a significant drop in ozone levels over their station in Antarctica. This shocking discovery led to the rapid adoption of the Montreal Protocol.
Which chemical family was introduced as a transitional replacement for CFCs because they are less damaging?
Correct Answer: A. HCFCs
Hydrochlorofluorocarbons (HCFCs) contain hydrogen, which makes them less stable and more likely to break down before reaching the stratosphere. While they still deplete ozone, their impact is much lower than CFCs. They are also currently being phased out in favor of zero-ODP alternatives.
What is the primary biological consequence of increased UV radiation due to ozone thinning in humans?
Correct Answer: C. Skin cancer and cataracts
UV radiation can damage the DNA in skin cells, leading to various types of skin cancer. It also causes protein damage in the eyes, which results in cataracts over time. Protecting the ozone layer is therefore a critical public health priority.
Which of the following is NOT an ozone-depleting substance?
Correct Answer: C. Carbon Dioxide
Carbon dioxide is a major greenhouse gas but it does not directly react with or destroy ozone molecules. Substances like Carbon Tetrachloride and HCFCs contain chlorine or bromine that can destroy ozone. Managing these specific chemicals is the focus of the Montreal Protocol.
The Kigali Amendment to the Montreal Protocol was adopted in which year?
Correct Answer: B. 2016
The Kigali Amendment was adopted in October 2016 in the capital of Rwanda. It targets the phase-down of HFCs to help prevent up to 0.5 degrees Celsius of global warming by the end of the century. This addition expanded the protocol's role in climate change mitigation.