Question

Why do the south-east trade winds become the south-west monsoon?

Answer 1

• During summer season as land gets heated up, the air rises and low pressure area is created on the land and on the other hand high pressure area is created in Indian Ocean. Air moves from high pressure areas to lower pressure areas.
  
• The low pressure land system attracts south-east trade winds but after crossing equator due to Coriolis force (Ferrel’s law is followed by Coriolis force according to which any moving mass in the rotating system like earth experiences a force that deflects it towards right in northern hemisphere and to the left in southern hemisphere) wind turn right towards the low-pressure areas over the Indian subcontinent. These winds start blowing in a southwesterly direction, and enter the Indian peninsula as the south-west monsoon.