Question

The news media typically blames carbon dioxide for being responsible for global warming. While CO2 indeed plays a dominant role, why are we also concerned about methane?

a. Methane is the second largest contributor to global warming

b. Methane is 26 times more potent as a greenhouse gas than CO2

c. Methane concentrations have been increasing in the atmosphere in recent years

d. Methane is produced both, naturally and anthropogenically

e. All of the above

Answer 1

The Correct answer will be option 'e' i.e. all of the above. Global warming may be defined as the increase in the average temperature of the earth. Within the last 100 years, it has been increase by a little less than 1°C. The major gases which are responsible for global warming are CO​​​2 , METHANE , nitrous oxide, CFCs, sulfur hexafluoride etc. Largest contributor to the global warming is CO​​​​​2 as the byproduct of emission of fossil fuels. After CO2, METHANE is the main culprit. Global warming potential of greenhouse gases is the relative measure of how much heat a greenhouse gas traps in atmosphere. Heat absorbing capacity of each gas is measured as compared to CO2 and it is calculated over a specific time interval like 20, 50 and 100 years. The 100 year global warming potential of methane is about 25 i.e. if the same mass of CO2 and METHANE is introduced in atmosphere, METHANE will trap 25 times more heat than CO2 over the next 100 years. Source of methane is rice crop, agriculture allied with dairy farming, natural wetland etc. So both naturally as well as man made methane is being produced. In recent years with increase in population the METHANE concentration is also increased in the atmosphere.