Asian countries are likely to experience rainy seasons, mostly within the southern and eastern part of the continent. At some point, these rain-bearing winds become more severe and persistent, and affect a wider area than the usual rains and other forms precipitation. This phenomenon came to be known as monsoon.
The word “monsoon” originated from the Arabic “mawsim” which means “season” or “weather.” It is used to describe a particular weather pattern characterized by constant blowing of moist ocean wind towards the continent, causing sustained, heavy rains on a large scale. It can be felt in many different countries around the world like those located in Asia, Australia, Africa, and west coast of U.S.
The phenomenon is a result of uneven heat distribution, wind direction, and Coriolis effect. It occurs mostly in parts of the continent adjacent to the ocean. Large masses of land heats up faster than the adjacent ocean waters, and thus will have warmer air compared to that of the ocean.
As warm air from the continent rise, it leaves behind areas of low atmospheric pressure. Consequently, cool ocean air moves inland towards these low pressure areas, bringing rainclouds and heavy precipitation.
Due to its particular movement from sea to land, this type of monsoon is sometimes referred to as “sea breeze.” Monsoons, however, are much broader in scope and more powerful than the typical sea breeze. The reverse can also happen in some other countries where land air is cooler than the ocean’s – the so-called winter monsoon or “land breeze.”
Monsoon Devastating Effects
Countries that have been severely affected by the recent monsoon experienced heavier than usual precipitations and typhoons. Thailand is among the worst hit countries, with over 200 dead and billions of dollars worth in damages.
Some believe this extreme type of monsoon is a byproduct of climate change. Others link this phenomenon to several other factors such as global warming and thinning of the ozone layer. Further studies are being made to determine whether these disturbances have significant effects to the recent and future occurrences of this phenomenon.
Monsoon can also blow the other way around when the air is cooler on land than on sea. Thailand experiences both kinds alternately. South-West Monsoon that blows inland usually occurs during the months of June to September. As winter time approaches, wind reverses direction and blows towards the sea due to continent’s cooler air temperature. This happens during the months of November to January. Between these two monsoons is an interlude of extremely hot temperatures during the summer months of March to May.