All questions of Climate for SSC CGL Exam

Understanding the Impact of El Niño on Monsoon and Cyclogenesis
El Niño is a significant climatic phenomenon that disrupts weather patterns globally, particularly affecting the Indian subcontinent's monsoon and cyclone formation in the Bay of Bengal.
What is El Niño?
- El Niño refers to the periodic warming of surface waters in the central and eastern tropical Pacific Ocean.
- This warming influences atmospheric conditions, leading to varied weather patterns worldwide.
Effects on Monsoon Rainfall
- Reduced Rainfall: El Niño is associated with below-average rainfall in India during the southwest monsoon season.
- Shifted Weather Patterns: Changes in ocean temperatures affect the Indian Ocean Dipole, altering monsoon wind patterns and precipitation distribution.
Impact on Cyclogenesis in the Bay of Bengal
- Favorable Conditions Disrupted: El Niño creates conditions that are less conducive for cyclones, reducing cyclogenesis (the formation of cyclones) in the Bay of Bengal.
- Increased Wind Shear: It enhances vertical wind shear, which inhibits the organization and strengthening of cyclonic systems.
Conclusion
Overall, El Niño plays a crucial role in adversely affecting monsoon rainfall and cyclone activity in the Bay of Bengal. Understanding its impacts is essential for better prediction and management of agricultural and disaster preparedness in the region.

The Himalayas act as a climatic barrier, diverting the rain-bearing southwest monsoon winds. As a result, the wind branches into two, one flowing along the plain regions towards northwestern India, and the other towards Southeast Asia. This diversion leads to reduced rainfall in northwestern parts of India, creating the rain-shadow effect in regions like Delhi and Haryana.

Understanding Cyclones in the Bay of Bengal
The Bay of Bengal is a significant region for cyclone formation, especially during the southwest monsoon season. The primary reason for this phenomenon is the presence of easterly trade winds.
Role of Easterly Trade Winds
- Warm Ocean Waters: The Bay of Bengal experiences warm sea surface temperatures, which are conducive for cyclone formation.
- Easterly Trade Winds: These winds blow from east to west and contribute to the development of low-pressure systems over the warm waters.
- Convergence and Instability: The easterly trade winds help in the convergence of moist air, leading to instability in the atmospheric conditions necessary for cyclone development.
Impact on Weather Conditions
- Enhanced Rainfall: Cyclones formed in the Bay of Bengal during the monsoon season often lead to heavy rainfall, significantly affecting the weather patterns in the region.
- Flooding Risks: The intense rainfall associated with these cyclones can cause flooding in coastal and inland areas.
- Agricultural Impacts: The weather conditions influenced by these cyclones can affect crop yields, impacting the agricultural sector.
Other Options Explained
- Influence of El Niño: While El Niño can affect global weather patterns, its primary impact is not directly associated with cyclones in the Bay of Bengal during the southwest monsoon.
- Originating in the Arabian Sea: Cyclones can also form in the Arabian Sea, but the Bay of Bengal is more prone to cyclones during the monsoon due to local conditions.
- Formation over the Himalayas: The Himalayas do not contribute to cyclone formation; instead, they can influence weather patterns by blocking monsoon winds.
In summary, the presence of easterly trade winds plays a crucial role in the formation of cyclones in the Bay of Bengal, thus influencing weather conditions during the southwest monsoon season.

The rain-shadow effect in India, leading to arid to semi-arid conditions on the leeward side, is caused by orographic upliftment. Windward sides of orographic barriers receive more rainfall, leaving the leeward side drier.