Question

Montreal protocol, which calls for appropriate action to protect the ozone layer from human
activities was passed in the year
A) 1986
B) 1987
C) 1988
D) 1985

Answer 1

Hint:- The Montreal Protocol on Substances that Deplete the Ozone Layer or the Montreal Protocol is an international agreement to protect the ozone layer. It was proposed by the United Nations Environment Programme (UNEP) . As a result of the continuous efforts of this treaty, the ozone hole over Antarctica is recovering. This protocol aims to regulate the consumption and production of ozone-depleting substances such as chlorofluorocarbons (CFCs) and other groups of such halogenated carbons.

Complete solution:
The sun emits harmful ultraviolet rays towards the earth but the ozone which surrounds the earth provides a protective shield against these rays. Due to the presence of ozone-depleting substances in the atmosphere, the ozone layer has been badly damaged and there is the formation of "ozone holes". Ozone is an inorganic molecule containing three oxygen molecules. It is less stable than molecular oxygen and is a pale blue gas having a pungent smell. Several harmful diseases such as skin cancer and cataract are caused by the UV-B light emitted from the sun. It can also cause immune system suppression. Therefore, protection of the ozone layer is important.
The ozone-depleting substances such as CFC react with the ozone molecule and break its bonds. There is the formation of an oxygen molecule and an oxygen radical that combines with the CFC. As a result, the ozone layer breaks down and an oxygen molecule is released.
The Montreal Protocol includes control measures that are to be followed by the countries in agreement with it. The developed countries and developing countries both have different measures to control ozone depletion . This treaty has various reforms over the years with the advent of new scientific, technological, and economic development.
The Montreal Protocol was passed in the year 1987. Therefore the correct answer is B.

Note:- The Montreal Protocol is the only treaty that is ratified by all the countries. With this protocol in effect, the ozone layer is slowly recovering and is expected to be recovered by 2050, if all control measures are strictly followed. The ozone-depleting substances contain bromine compounds, in addition to fluorine compounds. These substances are found in refrigerators, air conditioners, aerosols, and other products.