the monsoons demarcate a type of climatic variation that occurs in the southern and southeastern parts of Asia, which is why it is also called Monsoon Asia. It is an atmospheric phenomenon that favors the occurrence of intense rains in one period of the year and severe droughts in another.
Monsoon winds are characterized by varying their direction as the seasons change. Now its movement goes from the Indian Ocean to the continent, characterizing the summer monsoon or maritime, now it goes from the Asian continent to the ocean, featuring the winter monsoon or continental.
During the summer monsoon, rains are extremely intense. Photograph taken in Varanasi, India. ¹
During the summer, the humid air masses coming from the ocean favor the formation of clouds that precipitate in the form of strong storms during much of the year. For this reason, India – the main country affected by the monsoons – had the highest rainfall rates ever. During winter, the air masses start to move towards the ocean, making the climate extremely dry in the region.
Groups of Indian women in search of water, increasingly scarce during the continental monsoon period, in the dry winter
How do monsoons arise?
We know that the Earth heats up or cools down much faster than water. We also know that warm air always travels upwards and cold air always travels downwards. In addition, low pressure zones (lesser amount of air) tend to be “filled in” by the air that is in higher pressure zones, generating winds.
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During summer, the continent tends to heat up faster than the ocean. While the first stays at an average temperature of 40ºC, the second stays at 20ºC. This makes the air on the continent warmer and rises to the higher parts of the atmosphere, which causes the humid air existing over the ocean moves quickly to this region, which starts to suffer from the rains in this region. time course. And the maritime monsoon.
During winter, the humid air that was concentrated on the continent starts to move towards the ocean, which at that time has a lower atmospheric pressure. With this, the humidity of the continent is considerably reduced, providing the occurrence of an extensive and severe period of drought. In 1770, this drought was so intense that it killed thousands of people in south-eastern India. And the continental monsoon.
Scientists have recently discovered that this air displacement that characterizes monsoons is so which accelerated the movements of the Indian tectonic plate by 20% over the last 10 million of years old.
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¹Image credits: MR and Shutterstock
By Rodolfo Alves Pena
Graduated in Geography
Would you like to reference this text in a school or academic work? Look:
PENA, Rodolfo F. Alves. "Monsoons"; Brazil School. Available in: https://brasilescola.uol.com.br/geografia/moncoes.htm. Accessed on June 27, 2021.
