UPSC Mains 2022 GS3 Q7 — Environmental Pollution
Discuss in detail the photochemical smog emphasizing its formation, effects and mitigation. Explain the 1999 Gothenburg protocol. (Answer in 150 words)
Question Decoded — examiner's intent
- Directive verbs
- DiscussemphasizingExplain
- Scope keywords
- photochemical smogformationeffectsmitigation1999 Gothenburg protocol
- Implicit sub-parts
- Chemical precursors and catalysts involved in the creation of 'Los Angeles smog'.
- Primary vs. Secondary pollutants in the context of solar radiation.
- The specific evolution of the Gothenburg protocol (from 1999 to 2012 amendments) regarding VOCs and NOx.
- Health and ecological impacts specific to ozone and PAN.
- Common pitfalls
- Confusing photochemical smog with classical/London smog (sulfur-based/winter).
- Failing to mention the role of sunlight (UV radiation) as the essential trigger.
- Describing general air pollution mitigation instead of specific VOC and NOx control measures.
- Defining the Gothenburg Protocol only as a generic 'pollution treaty' without mentioning its focus on Acidification, Eutrophication, and Ground-level Ozone.
- Dimensions required
- Atmospheric ChemistryPublic HealthEnvironmental PolicyInternational Environmental Law
- Marks allocation hint
Dedicate 30 words to the chemical reaction mechanism (NOx + VOC + Sunlight), 40 words to impacts and mitigation, and a substantial 50-60 words to the Gothenburg Protocol as it is a specific direct requirement. Reserve the remaining words for a concise definition and a concluding link to global air quality standards.
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