There are two chief types of variable winds — cyclones and anti-cyclones.
- Cyclones are variable winds. In low latitudes, an intense depression with low-pressure conditions develops, known as tropical cyclones. These last only for few days.
- Because of the Coriolis Effect, the cyclones blow in an anti-clockwise direction in the Northern Hemisphere and clockwise in the Southern Hemisphere.
- Cyclones are associated with turbulent weather, cloudy weather, strong winds, and intense rainfall.
- A Tornado is a tropical cyclone that occurs over land. It is a funnel-shaped cloud extending downwards from the base of the thunderstorms. They may travel at a high speed of 500–800 km per hour. They are generally experienced over tropical waters in North America.
- Hurricanes and typhoons are some other tropical cyclones.
- Temperate cyclones are active over mid-latitudinal regions between 35° and 65° latitude in both hemispheres.
- Anti-cyclones represent calm weather. Winds blow gently in the clockwise direction in the Northern Hemisphere and in the anti-clockwise direction in the Southern Hemisphere.
Differences between cyclones and anti-cyclones
|It is a low-pressure system with surroundings of high pressure.||It is a high-pressure system with surroundings of low pressure|
|It blows anti-clockwise in the Northern Hemisphere.||It blows clockwise in the Northern|
|It blows clockwise in the Southern Hemisphere||It blows anti-clockwise in the Southern Hemisphere.|
|It is associated with cloudy skies, heavy rainfall with stormy winds.||It is associated with clear skies, mild winds, and dry conditions.|
|It can cause great damage to life and property if precautions are not taken.||The weather is settled and pleasant.|
- Jet streams are winds that blow horizontally from west to east at a high speed near the tropopause and the stratosphere. These are high-speed winds that influence the weather and climatic conditions of the region over which they blow.
- There are two types of jet streams that blow at a tropical belt of 300 north latitudes—the westerly jet stream and the easterly jet stream.
- A branch of the Westerly jet stream brings moderate to heavy rainfall followed by cold waves in the Indian subcontinent.
- The Easterly jet stream also helps the monsoon winds to blow into the greater part of India and bring monsoon showers.
Also, Read Pressure belts and types of winds