Basic Mechanical Engineering (3110006)

BE | Semester-1   Summer-2019 | 04-06-2023

Q2) (a) 

Discuss the factors responsible for global warming and ozone depletion

Factors responsible for global warming:
  • Most Greenhouse gases are generated by mankind, Vehicles burning Fossil fuels and Deforestation.
  • Global warming is caused by excessive quantities of greenhouse gases emitted into Earth’s near-surface atmosphere.
  • Greenhouse gases are both man-mad and occur naturally, and include a number of gases, including: carbon dioxide, methane, nitrous oxide, chlorofluorocarbons and water vapor.
Factors responsible for ozone depletion:
  • The ozone layer depletion is a major concern and is associated with a number of factors.
     
    The main causes responsible for the depletion of the ozone layer are listed below:
     
  • Chlorofluorocarbons
    • Chlorofluorocarbons or CFCs are the main cause of ozone layer depletion. These are released by solvents, spray aerosols, refrigerators, air-conditioners, etc.
    • The molecules of chlorofluorocarbons in the stratosphere are broken down by the ultraviolet radiations and release chlorine atoms. These atoms react with ozone and destroy it.
  • Unregulated Rocket Launches
    • Researches say that the unregulated launching of rockets result in much more depletion of ozone layer than the CFCs do. If not controlled, this might result in a huge loss of the ozone layer by the year 2050.
  • Nitrogenous Compounds
    • The nitrogenous compounds such as NO2 , NO , N2O are highly responsible for the depletion of the ozone layer.
  • Natural Causes
    • The ozone layer has been found to be depleted by certain natural processes such as Sun-spots and stratospheric winds. But it does not cause more than 1-2% of the ozone layer depletion.
    • The volcanic eruptions are also responsible for the depletion of the ozone layer.

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