Wind, Storm and Cyclones

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What is Wind?

The flow of gases or movement of bulk of air on the surface of Earth is Wind. Various attributes of the wind include the types of forces that cause them, the regions in which they occur, and their effect, wind speed and spatial scale. Wind also occurs in outer space called the solar wind. It involves the movement of charged particles and gases from the sun through space. Wind speed, the density of gas that’s causing the wind, wind energy are all different aspects of it. It has its own strength and direction of flowing.

Wind Currents

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Increase in wind speed accompanies the reduction in air pressure, which is basically a pressure exerted by the air around us. This is also followed by the movement of air from the high-pressure region to the low-pressure region. So, wind currents are air currents of considerable force moving mostly in the horizontal direction from an area of high pressure to are of low pressure. Air becomes light on heating, because it expands, and in order to occupy more space due to expansion it rises up. Warm air is lighter than cool air which can be illustrated from the fact that smoke always rises up.

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Storms are generated when a centre of low pressure develops with the system of high pressure surrounding it. It is marked by high wind moving at great wind speed. The regions that lie close to the equator receive more heat from the sun. Due to this, the warm air rises up. This suggests that the warm air from the equator moves in to take its place. On the other hand, the air on poles is colder than the air at the equator. Thus, as the warmer air rises up, the cooler air from the poles race in. Consequently, wind currents move from poles to warmer latitudes due to the uneven heating of the earth’s surface.

There are many types of storms like Dust storm, in which the visibility gets badly impacted as the wind picks up large quantities of sand, soil. Hailstorm which occurs due to precipitation of chunks of ice. Ice storm, that is one of the most dangerous forms of winter storms. It occurs when surface temperatures are below freezing, but a thick layer of above-freezing air remains aloft, rain can fall into the freezing layer and freeze upon impact into a glaze of ice. The snowstorm is characterized by heavy snowfall.  Thunderstorms, Cyclones, and so on.


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A thunderstorm is characterized by the presence of lightning along with thunder. Generally, it develops in hot and humid regions like India. High temperature creates strong and upward currents. These currents carry moisture, that is, water vapour along with them to higher altitudes. This is followed by the process of condensation and rain again. These pressure variations are accompanied by thunder, lightning and strong winds.

Conversion of Thunderstorm to Cyclone

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When moisture changes to the liquid form of water, that is, water drops, it leads to release of heat to the atmosphere. Thus, the heat released in this way warms the surrounding air and gives rise to a pressure drop. All of these consequences lead the air to rush in towards the centre of the storm. This cycle creates large low-pressure systems with strong high-speed winds swirling around it. This is how the cyclone forms.


  • A cyclone is a huge mass of rotating air that has a speed of nearly 1015 km high in the air.

  • The centre of the cyclone is calm and is known as the eye of the storm.

  • The eye of the storm mostly has a diameter ranging from 10 to 30 km.

  • Around the eye of the storm, lies a region of clouds of about 150 km. The speed of wind inside it is about 150-250 km/hr.

  • The speed of the wind decreases as it moves away from the eye of the storm.

  • Cyclones are also called Hurricanes or Typhoons.

FAQ (Frequently Asked Questions)

1. What is a Tornado?

A tornado is a type of violent and destructive storm occurring within the cyclone. It has the shape of a rotating funnel and it acts like one by sucking in debris, dust, and everything else in the bottom and throws them out at the top.

It may have a speed of about 300 km/hr and a diameter ranging from a meter to a kilometre long.

2. How are Rains Caused?

When winds from the ocean and seas flow towards the land, they carry moisture along. This moisture in the clouds gets saturated after a point. Within the cloud, the water droplets condense onto one another. This type of condensation causes water droplets to grow. When the water droplets get too heavy that they cannot remain suspended anymore, they fall down in the form of rain.

3. What are the Safety Measures if a Cyclone Ensues?

  • Avoid taking refuge under isolated trees.

  • If in a forest, seek shelter under a small tree and do not lie on the ground

  • Do not try taking cover under an umbrella

  • Avoid sitting near metal sheds or open garages

  • If in water, rush out and go inside a building or at a safe place.