Question

The most abundant greenhouse gas in the earth’s atmosphere
A. Carbon dioxide \[\left( {C{O_2}} \right)\]
B. Nitrous oxide \[\left( {{N_2}O} \right)\]
C. Water vapor \[\left( {{H_2}O} \right)\]
D. Methane \[\left( {C{H_4}} \right)\]

Answer 1

Hint: Greenhouse gases contribute to the greenhouse effect. The term greenhouse effect has been derived from a similar phenomenon that occurs in the greenhouse. The most abundant gas is the aqueous phase of the gas in the atmosphere.

Complete answer: The greenhouse lets the sunlight in but it does not let the heat escape. The greenhouse warms up the space similar to a car that is parked in the sun for hours. The greenhouse effect is responsible for increasing the temperature of the earth.
a) Carbon dioxide \[\left( {C{O_2}} \right)\] - Carbon dioxide is a major greenhouse gas. This is because the relative contribution of carbon dioxide to global warming is about sixty percent when compared with anthropogenic greenhouse gases. As compared to other greenhouse gases in the atmosphere, the contribution is a mere four percent.
b) Nitrous oxide \[\left( {{N_2}O} \right)\] - Nitrous oxide is a minor greenhouse gas. This is because the relative contribution of nitrous oxide to global warming is about six percent, when compared with anthropogenic greenhouse gases. As compared to other greenhouse gases in the atmosphere, the contribution is very insignificant and lies somewhere within the range of two percent.
c) Water vapor \[\left( {{H_2}O} \right)\] - Water is the most important greenhouse gas. This is because the relative contribution of water to global warming is about ninety-six percent in the atmosphere, which is very high.
d) Methane \[\left( {C{H_4}} \right)\] - Methane is a major greenhouse gas. This is because the relative contribution of methane to global warming is about twenty percent, when compared with anthropogenic greenhouse gases. As compared to other greenhouse gases in the atmosphere, the contribution is very insignificant and lies somewhere within the range of two percent.
Thus, based on the above information we can conclude that the most abundant greenhouse gas in the earth’s atmosphere is water vapour.
Hence, the correct answer is option C.

Note: The most important effect of global warming is the ozone hole. The thinning of the ozone layer and the ozone hole is caused due to the increase in the concentration of greenhouse gases in the atmosphere. A massive hole was observed above Antarctica.