Types of Winds
Following are the types of wind-
The winds that blow continuously throughout the year in the earth are called eternal, fixed or permanent winds. The direction of these winds is fixed and unchanging. It includes westerly, trade and polar winds.
Perpetual (permanent) winds blowing from the subtropical high pressure zones to the subpolar low pressure areas in both the hemispheres are called westerly winds because of their westward movement. The direction of these winds is from North-West to South-East in the Southern Hemisphere and from South-West to North-East in the Northern Hemisphere. Due to the absence of land blocks between 40° to 65° latitudes in the Southern Hemisphere, there is an uninterrupted circulation of these winds. Thus, due to the absence of obstruction in the southern hemisphere, westerly winds blow with great velocity and sound. Sailors have called these terrible winds ‘roaring chalisa’ between 40° to 50° south latitudes, the fierce Pachasa near 50° south latitude and the screaming Satha near 60° south latitude. These winds bring rain on the western continental coasts. Special rainfall is caused by these winds in the north-west countries.
(2) Polar winds
Polar winds blow from cold pole regions to subpolar low pressure areas between 60°/70° latitudes in both hemispheres. They flow in the north-east direction in the northern hemisphere and south-east in the southern hemisphere. Due to the very cold and snowy nature of these winds, the areas coming in contact with them have severe winters. When polar winds come in contact with westerly winds, cyclones and anticyclones are born. Due to these winds, snow accumulates in the central plains of Siberia and America.
(3) Commercial winds
Calm winds are found at 5° north and 5° south of the equator . After this the winds which are in the north and south latitudes from 5 ° to 30 °, are called convective or trade winds. The direction of these winds is north-east in the northern hemisphere and south-east in the southern hemisphere. These winds blow throughout the year. Monsoon winds bring changes in their sequence in summer. These winds bring good rainfall in the eastern parts of the continents.
2. Temporary winds
Due to the local special conditions of temperature and air pressure, winds also start blowing. Their direction varies according to season, season and time. That is why they are also called temporary, occasional or periodic winds.
(1) Local winds
Local winds are generated due to air pressure and temperature conditions. Their flow is limited to a particular place. They are known by different names in different places.
(2) Monsoon wind
These winds blow according to the seasons. These are both terrestrial and aquatic winds. According to the fixed season, these winds blow from sea to land for 6 months and from land to sea for 6 months. Their area is the region of the trade winds. They break the form of merchant winds. Rainfall in India is caused by monsoon winds. Monsoon winds change their direction according to the season and blow for a certain season and in a definite direction. Monsoon lines always run between the lines of peace on the eastern coasts of the continents. Their flow outside Asia is up to 60° north latitude. Asia is most affected by monsoon winds in the world. For 6 months these winds blow from the North-East and for 6 months from the South-East. They are born due to unequal conditions of water and land. In summer, these winds blow from the sea to the land, so These are called summer monsoons. They cause a lot of rainfall in the South-East Asia regions. In winter, these winds blow from land to sea, due to which they are called winter monsoon. These winds bring rain in the eastern archipelago, off the coast of Tamil Nadu, Sri Lanka and northern Australia in India.