'Monsoon wind is known for its uncertainties’. Explain it by giving four reasons

'Monsoon wind is known for its uncertainties’. Explain it by giving four reasons.

The climate of India is strongly influenced by monsoon winds. The duration of the monsoon is between 100-120 days from early June to mid-September. Monsoon winds is known for its uncertainties because

  1. The movement of low pressure trough controls the spatial distribution of rainfall as the trough and its axis keep on moving northward or southward.

  2. The alteration of wet and dry spells varies in intensity, frequency and duration. When the axis shifts closer to the Himalayas, there are longer dry spells in the plains, and widespread rain occur in the mountains.

  3. It sometime causes heavy floods in one part, it may be responsible for drought in other.

  4. It is often irregular in its arrival and retreat.