Cyclones or hurricanes have immense destructive power. They cause suffering and destruction, wherever they meet the inhabited coastlines. But how are cyclones formed? And what makes cyclones so dangerous? Let’s find out.
Cyclone arises along the polar frontal zone and takes advantage of the strong western high currents and the large temperature contrasts between polar and subtropical air masses. Cyclones have hot and cold fronts and ensure the mixing of these two air masses. The winds within a cyclone turn counterclockwise in the northern hemisphere and vice versa in the southern hemisphere. Cyclones are a decisive factor for the central European weather. They are responsible for the changeable weather and ensure sufficient rainfall all year round. In the winter half of the year, cyclones are significantly stronger than in the summer half due to the larger temperature contrasts at the frontal zone. In individual cases, they can even cause damage from storms and heavy rainfall as storm or cyclone lows. Let’s find out how are cyclones formed.
The eye of the storm
When it evaporates, air flows in from all sides. Because the earth is spinning, the air masses begin to spin like a spiral. This creates a huge vortex. The middle part of this vortex is also called the EYE. It is very quiet in this area, but a huge storm circle around it and that is how cyclones are formed. Only when the cyclone comes across mainland or cooler water, it runs out of steam or heat.
Incidentally, such cyclones also occur over other oceans. They are called by different names in different regions. If they form over the Atlantic Ocean, they are called a HURRICANE or CYCLONE, and if they originate over the Pacific in Asia, they are called TYPHOONS.
Different directions
The direction of the vortex depends on the location of a cyclone. In the northern hemisphere, the cyclone turns counterclockwise, whereas, in the southern hemisphere, it turns clockwise.
How Are Cyclones Formed
The sun burns vertically on the area around the equator and heats the upper water layer of the ocean to at least 27 degrees Celsius. As a consequence, the water evaporates, moist, warm air expands and rises like a chimney. This movement creates a low-pressure area, into which air now flows in from all directions.
Where air flows, winds are created. What is special about this is that these winds do not go straight into the heart of the low. They are distracted by the rotation of the earth. It is called a Coriolis force, and it causes the air currents to circle around the low. The moist air masses whirl upwards like on a corkscrew path, cool down there, and form bands of thick storm clouds, from which it rains relentlessly with lightning and storms.
A dangerous chain reaction
As the storm clouds grow, however, heat is released again. It lets the air parcels that have already risen rise even higher, and air flows in again from below. This chain reaction of ascent, cloud formation, raining down, the further ascent starts again and provides the cyclone with new strength every time provided that the incoming air is warm and humid.
Because of this constant self-reinforcement, cyclones can grow to an area of 1000 kilometers in diameter. In satellite photos, they then look like huge whirlpools that rotate around a cloud-free hole, the so-called eye of the storm.
Also Read- How Are Black Holes Formed
How cyclones are formed and the strength of the cyclones, depends on many factors like temperature, pressure, humidity, the rotation of earth and its location. These cyclones near the coast are particularly dangerous because they can trigger tidal waves up to ten meters high, which can cause a lot of damage to life and make people homeless as well, especially in densely populated countries like India. One of the heaviest cyclones hit the coast of East India in October 1999 with wind speeds of over 260 kilometers per hour. It cost more than 10,000 lives and sank more than 50 ships in the port of the Indian city of Paradip.