question_answer 1)

  Green plants use carbon dioxide for photosynthesis and return oxygen to the atmosphere, even then carbon dioxide is considered to be responsible for greenhouse effect. Explain why?

Answer:

  Carbon dioxide is a natural constituent of atmosphere and is vital for all forms of plant life. It forms about 0.033% by volume of atmosphere. It helps to maintain the temperature of the earth required for the living organisms. A balance of \[C{{O}_{2}}\]is maintained in air because \[C{{O}_{2}}\] is produced from respiration, burning of fossil fuels and decomposition of lime stone but at the same time it is consumed in photosynthesis by plants. However, human activities have disturbed this balance and\[C{{O}_{2}}\] level in atmosphere is in increasing order. This has happened due to deforestation, burning of more of fossil fuels and industrialization. It has been estimated that \[C{{O}_{2}}\]concentration has risen about 25% in the past century. During the past nearly 120 years, the average temperature of the planet has increased by somewhere between 0.4 and\[0.8{}^\circ C\]. Current estimates are that doubling the \[C{{O}_{2}}\]concentration will result in a temperature increase of between 1.0 and\[3.5{}^\circ C\]. The greenhouse effect contribution of \[C{{O}_{2}}\] is 50% and of other trace gases is also about 50%.