Q. Discuss in detail the photochemical smog emphasizing its formation, effects and mitigation. Explain the 1999 Gothenburg Protocol. [150 words, 10 Marks]
Why the Question?
UPSC PYQ – CSE Mains – 2016
Keywords of the Question
- Photochemical smog
- Formation, effects and mitigation
- 1999 Gothenburg Protocol
Directive Word
Discuss – Essentially this is a written debate where you are using your skill at reasoning, backed up by carefully selected evidence to make a case for and against an argument, or point out the advantages and disadvantages of a given context. Remember to arrive at a conclusion
How to approach this Question?
Introduction
- Define photochemical smog.
- Briefly mention its significance and relevance.
Body
- Formation:
- Explain the chemical reactions involved.
- Identify primary and secondary pollutants.
- Mention conditions that favor its formation.
- Effects:
- Impact on human health.
- Environmental and ecological effects.
- Mitigation:
- Strategies to reduce emissions.
- Technological and policy measures.
- 1999 Gothenburg Protocol
Conclusion
- Summarize the importance of addressing photochemical smog.
- Introduce the 1999 Gothenburg Protocol.
- Highlight its role in mitigating photochemical smog and improving air quality.
Note: Please note that the following ‘answers’ are not ‘model answers’ nor are they synopses in the strictest sense. Instead, they are content designed to meet the demands of the question while providing comprehensive coverage of the topic.
Answer Key
Introduction
Photochemical smog, also known as “summer smog,” is a type of air pollution formed through the reaction of sunlight with pollutants such as nitrogen oxides (NOx) and volatile organic compounds (VOCs). This phenomenon is particularly prevalent in urban areas with high traffic emissions and industrial activities.
Body
Formation:
- Chemical Reactions: Photochemical smog forms when sunlight triggers chemical reactions between NOx and VOCs, producing secondary pollutants like ozone (O3), peroxyacetyl nitrate (PAN), and other photochemical oxidants.
- Primary Pollutants: NOx and VOCs are emitted from vehicles, industrial processes, and power plants.
- Conditions Favoring Formation: High temperatures, stagnant air, and intense sunlight enhance the formation of photochemical smog.
Effects:
- Human Health: Exposure to photochemical smog can cause respiratory problems, eye irritation, and aggravate conditions like asthma and bronchitis.
- Environmental Impact: It can damage crops, forests, and aquatic ecosystems by reducing photosynthesis and increasing plant susceptibility to diseases.
- Material Damage: Photochemical smog can degrade materials like rubber, plastics, and paints, leading to economic losses.
Mitigation:
- Emission Reduction: Implementing stricter emission standards for vehicles and industries to reduce NOx and VOCs.
- Technological Measures: Adoption of cleaner technologies, such as catalytic converters in cars and scrubbers in industrial plants.
- Policy Measures: Promoting public transportation, carpooling, and the use of alternative fuels to reduce vehicular emissions.
- Public Awareness: Educating the public about the sources and effects of photochemical smog and encouraging environmentally friendly practices.
1999 Gothenburg Protocol:
- Objective: Reduce emissions of key pollutants, including NOx and VOCs, to mitigate photochemical smog.
- Measures: Setting national emission ceilings and promoting best practices.
- Impact: Improved air quality and protection of ecosystems through international cooperation.
Conclusion
Addressing photochemical smog is crucial for protecting public health and the environment. The 1999 Gothenburg Protocol plays a vital role in this effort by setting emission reduction targets and encouraging best practices among signatory countries. By implementing these measures, we can significantly reduce the formation of photochemical smog and ensure a healthier, more sustainable future.
Mind Map
