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Monsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea. Usually, the term monsoon is used to refer to the rainy phase of a seasonally-changing pattern, although technically there is also a dry phase. The major monsoon systems of the world consist of the West African and Asia-Australian monsoons. The term was first used in English in British India (now India, Bangladesh and Pakistan) and neighboring countries to refer to the big seasonal winds blowing from the Bay of Bengal and Arabian Sea in the southwest bringing heavy rainfall to the area. The south-west monsoon winds are called 'Nairutya Maarut' in India.

Definition

Monsoon, derived from the Arabic word "Mausim" meaning "season", although generally defined as a system of winds characterized by a seasonal reversal of its direction

• The American Meteorological Society defines it as a name for seasonal winds, first applied to the winds blowing over the Arabian Sea from northeast for six months and southwest for six months. Later it has been extended to similar winds in other parts of the world. • Intergovernmental Panel on Climate Change (IPCC) describes Monsoon as a tropical and subtropical seasonal reversal in both the surface winds and associated precipitation, caused by differential heating between a continental-scale land mass and the adjacent ocean. • Indian Meteorological Department defines it as the seasonal reversals of the wind direction along the shores of the Indian Ocean, especially in the Arabian Sea, that blow from the southwest during one half of the year and from the northeast during the other half. • Colin Stokes Ramage in Monsoon Meteorology, International Geophysics Series, Vol. 15, defines Monsoon as a seasonal reversing wind accompanied by corresponding changes in precipitation

Indian Monsoon

          India's climate is affected by two seasonal winds - the Southwest Monsoon and Northeast monsoon. The north-east monsoon, commonly known as Winter monsoon blows from land to sea, whereas south-west monsoon, known as Summer monsoon blows from sea to land after crossing the Indian Ocean, the Arabian Sea, and the Bay of Bengal. The south-west monsoon brings most of the rainfall during a year in the country. Monsoon or rainy season, lasting from June to September, is dominated by the humid South-West Monsoon that slowly sweeps across the country in early June. Monsoon rains begin to recede from North India in the beginning of October. Post-monsoon season, lasting from October to December, brings in more precipitation to South India. Southwest Monsoon (summer monsoon)

          During the summer, the continent of Asia heats up more than the surrounding ocean due to the differences in the way land and water heat. The warm surface creates a large area of low pressure over north-central Asia and a smaller one over India. The southwest summer monsoon is attracted to India by a low pressure area that's caused by the extreme heat of the Thar Desert and adjoining areas of the northern and central Indian subcontinent. Moisture-laden winds from the Indian Ocean rush in to the subcontinent to fill up the void, but because they can't pass through the Himalaya region, they're forced to rise. The gain in altitude of the clouds results in a drop in temperature, bringing rain. When the southwest monsoon reaches India, it splits into two parts. 1. Arabian Sea Branch

2. Bay of Bengal Branch
          The Arabian Sea Branch of the Southwest Monsoon first hits the Western Ghats of the coastal state of Kerala, thus making the area the first state in India to receive rain from the Southwest Monsoon. This branch of the monsoon moves northwards along the Western Ghats with precipitation on coastal areas, west of the...
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