Question

Montreal protocol is related to
A) Ozone depletion
B) Global warming
C) Climatic changes
D) Biodiversity hotspot

Answer 1

Hint:The Montreal protocol entered into force on 26 August 1989, and has undergo nine revisions in 1990 in London, 1991 in Nairobi, 1992 in Copenhagen, 1933 in Bangkok, 1995 IN Vienna, 1987 in Montreal, 1998 in Australia, 1999 in Beijing and 2016 in Kigali.

Complete answer:
The meeting was called for international cooperation in research and also empowered the United Nations Environment Programme (UNEP) to lay the groundwork for Montreal protocol.
Ozone depletion is responsible for a steady lowering of about 4% in the total amount of ozone in Earth’s atmosphere and decrease in stratospheric ozone around Earth’s polar regions. The main cause of Ozone depletion is chemicals especially manufactured halocarbon, solvents, refrigerants, propellants and chlorofluorocarbons also called ozone depleting substances (ODS). This ozone depletion generated worldwide concern over increased cancer risks and other negative effects. Ozone layer prevents harmful wavelengths of UV light from passing through the Earth’s atmosphere. These wavelengths are very harmful and can cause skin cancer, sunburn, blindness, cataract.
All of these concerns led to adoption of Montreal protocol in 1987 and it bans the production of CFCs, halons and other chemicals. After recognizing the hazardous effects of ozone depletion, Montreal protocol was signed at Montreal (Canada) in 1987 to control the emission of various ozone depleting substances.

The correct answer is Ozone depletion.

Note:The strengthening of Montreal protocol led to reductions in the CFCs emission. Global warming is the rapid increase in Earth’s average surface temperature due to greenhouse gases released by people burning fossil fuels.