Ozone & Protocols — Set 3
Environment · ओज़ोन और प्रोटोकॉल · Questions 21–30 of 50
What is the primary reason why the ozone hole is much larger over the South Pole than the North Pole?
Correct Answer: D. The Antarctic is colder with a more stable vortex
The Antarctic polar vortex is stronger and more isolated, allowing temperatures to drop much lower than in the Arctic. These extreme cold temperatures facilitate the formation of polar stratospheric clouds. These clouds are the primary sites for the chemical reactions that destroy ozone.
Under the Montreal Protocol, which substances were the first to be targeted for a complete phase-out?
Correct Answer: A. CFCs
Chlorofluorocarbons (CFCs) were the primary focus of the original 1987 treaty. They were widely used in refrigeration, aerosol sprays, and as cleaning solvents. Developed countries stopped most CFC production by 1996.
The term 'ODP' is often used in protocols; what does it stand for?
Correct Answer: D. Ozone Depletion Potential
Ozone Depletion Potential is a relative measure of how much damage a chemical can cause to the ozone layer. It is calculated relative to CFC-11, which has an ODP of 1.0. This value helps policymakers prioritize which chemicals to regulate first.
Which of the following describes the 'Chapman Cycle'?
Correct Answer: A. Natural ozone formation and destruction
The Chapman Cycle describes the natural process by which ozone is continuously made and broken down in the stratosphere. It involves oxygen molecules absorbing UV light to split into atoms, which then reform as ozone. This cycle maintains a steady-state level of ozone under natural conditions.
Which color is traditionally used in satellite imagery to represent areas of high ozone depletion?
Correct Answer: C. Blue/Purple
Blue and purple colors are used in NASA's ozone maps to indicate low levels of ozone (the 'hole'). Higher levels of ozone are usually shown in reds and yellows. This visual convention makes it easy to track the size of the ozone hole annually.
Which of the following is a common household item that historically used CFCs as propellants?
Correct Answer: D. Aerosol spray cans
CFCs were used as propellants in sprays for hair, deodorants, and pesticides because they are non-flammable. These sprays released CFCs directly into the atmosphere during use. Modern spray cans now use alternative gases like propane or butane.
Which year did the Montreal Protocol enter into force?
Correct Answer: C. 1989
The Montreal Protocol was signed in 1987 and became effective on January 1, 1989. It is widely considered one of the most successful environmental treaties in history. It has undergone several amendments to include more substances and stricter timelines.
What is the primary impact of ozone depletion on marine phytoplankton?
Correct Answer: A. Photosynthesis inhibition
The correct answer is 'Photosynthesis inhibition'. Excessive UV radiation damages the DNA and photosynthetic capacity of phytoplankton. Since phytoplankton are the base of the marine food web, their decline affects the entire ocean ecosystem. This can also reduce the ocean's ability to absorb carbon dioxide.
Which element is found in 'Halons' that makes them particularly damaging to the ozone layer?
Correct Answer: D. Bromine
Halons contain bromine, which is about 40 to 100 times more effective than chlorine at destroying ozone. They were mainly used in specialized fire protection systems for computers and aircraft. Because of their potency, they are tightly controlled under international law.
The 'Ozone Secretariat' is based in which city under the UNEP?
Correct Answer: D. Nairobi
The Ozone Secretariat is the administrative office for both the Vienna Convention and the Montreal Protocol. It is located at the UN Environment Programme headquarters in Nairobi, Kenya. It manages the day-to-day operations and organizes the meetings of the parties.