Topic– Geographical features and their location- changes in critical geographical features (including water bodies and ice-caps) and in flora and fauna and the effects of such changes.
1) Explain the mechanism of cloud formation? Discuss the impact of air pollution on rainfall patterns in India?(250 words)
Why this question
The question highlights the increase in the spate of erratic rainfall in India, and links it to the changes caused by air pollution. In GS1, UPSC at times asks questions linked to current happenings, and this would help you prepare about cloud formation as well as the impact of air pollution.
Key demand of the question
The question, in its first part, expects us to explain the factors impacting cloud formation, the mechanism of cloud formation. Next, we need to bring out how increasing air pollution has had an impact on rainfall patterns and the reasons for the same.
Discuss – Your discussion should focus on explaining how increasing air pollution has had an impact on rainfall patterns and the reasons for the same.
Structure of the answer
Introduction – Discuss the factors responsible for cloud formation – moisture, condensation nuclei. Explain how clouds are formed – condensation or deposition of water above the Earth’s surface creates clouds. In general, clouds develop in any air mass that becomes saturated (relative humidity becomes 100%). Saturation can occur by way of atmospheric mechanisms that cause the temperature of an air mass to be cooled to its dew point or frost point. The following mechanisms or processes can achieve this outcome causing clouds to develop:
- Explain the mechanism of cloud formation – clouds develop in any air mass that becomes saturated (relative humidity becomes 100%). Saturation can occur by way of atmospheric mechanisms that cause the temperature of an air mass to be cooled to its dew point or frost point, etc.
- Explain the change in pattern of rainfall – the erratic behaviour of monsoon rainfall, including the phenomenon of concentrated heavy rainfall on a small number of days, could, at least in part, be attributed to the rising air pollution. Explain that excess aerosols, suspended solid particles like dust, smoke and industrial effluents, in the atmosphere is changing cloud patterns, its shape, size and other properties like temperature, which in turn is resulting in variability in rainfall over the Indian sub-continent during the monsoon season.