The term monsoon comes from the Arabic mausim meaning 'season'. It is a seasonal change of wind direction which is associated with temperature changes between land and ocean in subtropical regions. It is characterized by large amounts of precipitation and countries are dependent upon its arrival. If there is no monsoon, a drought follows leading to a large economic impact on agriculture.

Examples:
  • India's climate is characterized by a two monsoons, the south-west monsoon and the north-east monsoon. The south-west monsoon brings rain to the west coast in the summer months and the north-east monsoon brings rains to the east coast between the months of October and December.
  • South-eastern Asia's (Indo-China, southern China, the South China Sea, and the Philippines) monsoon occurs from June to August.
  • The west African coast occurs year round but moves north beginning in February and reaches the northern part of the Sahel in May. The rains move south again in September.
  • Northern Australia's monsoon season occurs from November to April and is characterized by three major monsoon events with precipitation lasting well over seven days.