It is a period of transition from hot rainy season to dry winter conditions.
Explanation
The Retreating Monsoon, occurring during the months of October and November, represents the withdrawal of the Southwest Monsoon winds from the Indian subcontinent. This period marks a reversal in the wind patterns and atmospheric pressure conditions over the region.
Analysis of Options:
- It is marked by the strengthening of the low-pressure trough over the northern plains. is Incorrect: During the retreating monsoon, the low-pressure trough over the northern plains weakens and is gradually replaced by a high-pressure system. The low-pressure center shifts from the landmass towards the Bay of Bengal.
- It is a period of transition from hot rainy season to dry winter conditions. is Correct: The retreating monsoon is distinctively a period of transition from the hot rainy season to dry winter conditions. It is characterized by clear skies and an initial rise in temperature (often referred to as 'October Heat') before the onset of cooler winter temperatures.
- It brings widespread floods to the Ganga valley. is Incorrect: The retreating monsoon does not bring floods to the Ganga valley. Instead, the shift of the low-pressure zone to the Bay of Bengal generates cyclonic depressions that frequently cause heavy rainfall and potential flooding along the eastern coast of India (Coromandel Coast), particularly in Tamil Nadu and Andhra Pradesh.
- It is characterized by the inflow of western disturbances. is Incorrect: The inflow of Western Disturbances is a characteristic feature of the cold weather season (Winter), which typically impacts North and Northwest India from December onwards. It is not a primary feature of the retreating monsoon phase.
Key Takeaway:
The Retreating Monsoon is a transition phase characterized by the replacement of the low-pressure trough over the plains with high pressure, clear skies, and the shift of rainfall activity to the southeastern coast of India.