What Are the Major Effects of Cyclones on Communities?
What Are Cyclones?
As per meteorology, a cyclone is considered as a large scale air mass that is rotating around a strong center of low atmospheric pressure. In simple words, a cyclone is a general term used to categorize a weather system in which winds seem to rotate inwardly to an area where the atmospheric pressure is low.
In large weather systems, the pattern of circulation is in an anticlockwise direction in the northern hemisphere whereas in the southern hemisphere it circulates in a clockwise direction. There are three types of cyclones: tropical cyclones, extratropical cyclones, and tornadoes. Let us briefly discuss each of these cyclones.
Types of Cyclones
Tropical Cyclones
A tropical cyclone is considered as a rotating low-pressure weather system with some organized thunderstorms but no fronts. They are generally formed over ocean waters that are warm.
Tropical cyclones that have maximum sustained surface winds of less than 39 mph are known as tropical depressions. In contrast, tropical cyclones that have maximum sustained surface winds of 39 mph or higher are known as tropical storms. When the maximum sustained surface wind of a storm reaches 74 mph, then they are called hurricanes or typhoons.
Extratropical Cyclones
Extratropical cyclones are weather systems with a low-pressure which are formed outside the tropics as a response to the chronic instability of the westerly winds. This phenomenon takes place because this chronic instability depends on large horizontal temperature contrasts and concentrated regions of temperature change which are also known as fronts characterizing extratropical cyclones.
Tornado
A tornado can be considered as a rapidly rotating column of air that is moving downward, being generated by a thunderstorm, to the ground. The tornadoes can be violent and can cause tremendous destruction with wind speeds reaching as high as 300 mph.
Tornadoes form in those regions of the atmosphere which have an abundance of warm and moist air near the surface with drier air at the top, and a possible change in wind speed and direction, with a height above the ground.
Destructions and Consequences of Cyclone
We all are aware of the fact that cyclones can cause large-scale devastation. The death toll is high in regions that are hit by the calamity. Cyclones become the reason for the destruction of houses, buildings, transportation, electricity, and the death of livestock. The living beings inhabiting the region which is hit by the calamity are the most affected ones.
The destruction caused by the cyclone depends on the intensity, location, and size of the cyclone. Cyclones affect different regions in a different way. Cyclones affect the forest region by uprooting the trees and affecting the canopies. The banks and embankments get eroded due to cyclones in coastal regions. In desert areas, the dunes lose their original shape and get reshaped due to the cyclones. Landslides occur in the mountainous region due to cyclones.
The hazards caused by a cyclone when it hits a region is divided into the following three parts.
Primary Hazards
Strong winds, heavy rains, and storms come under primary hazards. There is an abnormal rise in sea level near the coasts due to which low-lying areas that are present near the coastal regions get submerged causing the drowning of humans, destruction of livestock and their inhabitations, destroying vegetation and soil fertility. Strong winds can cause damage to houses, trees and communication systems, etc. Primary hazards cause huge loss of human life as well as property and live stocks.
Secondary Hazards
Floods, fire, and freshwater flooding come under secondary hazards. Floods in the river are caused due to heavy rain which in turn causes submergence of the nearby inhabited regions. The floods also cause erosion of some fertile farming lands and destruction of many buildings as well as personal property. In forest regions, strong winds can cause forest fires which spread at an alarming rate due to the intensity of the wind. This can cause heavy damage to the forest and also to the wildlife. Many animals die due to these fires. This can also affect nearby regions with human habitats.
Tertiary Hazards
Tertiary hazards include diseases that are caused due to stagnant water, water poisoning, and a rise in the prices of goods and resources. Humans are the ones who are affected by the tertiary hazards. During these times people die due to a shortage of food. If not managed properly tertiary hazards can be terrifying than the primary and secondary hazards.
Through these hazards, students can get a clear idea of cyclones’ destructions and consequences.
FAQs on Cyclones: Destruction and Consequences in Physics
1. What are the main destructive elements of a cyclone?
A cyclone causes destruction primarily through three elements: strong winds, storm surge, and heavy rainfall. High-velocity winds can uproot trees, damage houses, and destroy communication towers. The storm surge is a rise in sea level that floods coastal areas, while torrential rains often lead to widespread inland flooding.
2. Why is the 'eyewall' of a cyclone the most destructive part, while the 'eye' is calm?
The 'eye' of a cyclone is a region of calm weather with light winds at the centre because cool, dry air is sinking. In stark contrast, the eyewall is a ring of towering thunderstorms surrounding the eye where the wind speeds are highest and rainfall is heaviest. This is due to the rapid upward movement of warm, moist air, making it the most dangerous and destructive part of the cyclone.
3. How does a storm surge caused by a cyclone lead to massive flooding?
A storm surge is an abnormal rise of sea water generated by a cyclone, over and above the normal astronomical tides. It occurs because the cyclone's extremely low atmospheric pressure in the centre pulls the water level up, creating a dome of water. The strong surface winds then push this dome towards the coast, causing it to pile up and inundate low-lying coastal areas with incredible speed and force, leading to severe flooding.
4. What are the long-term consequences for a region after being hit by a cyclone?
Beyond the immediate destruction, the long-term consequences of a cyclone can be devastating. These include:
- Infrastructure Damage: Destruction of roads, bridges, power grids, and communication lines can take months or years to repair.
- Economic Impact: Loss of agriculture, fisheries, and tourism can cripple the local economy.
- Health Crises: Contamination of water sources often leads to outbreaks of water-borne diseases like cholera and typhoid.
- Ecological Damage: Salination of soil from storm surges can make farmland unusable for a long time, and coastal ecosystems like mangroves can be severely damaged.
5. What are some effective safety measures to mitigate the consequences of a cyclone?
Effective safety measures are crucial for reducing the destructive impact of a cyclone. Key precautions include:
- Heeding official warnings issued by the India Meteorological Department (IMD) and moving to designated cyclone shelters if advised.
- Preparing an emergency kit with essentials like water, non-perishable food, first-aid supplies, and a torch.
- Securing your home by boarding up windows, clearing loose items from outdoors, and checking the roof.
- During the cyclone, staying indoors away from windows and avoiding all travel.
- After the cyclone, being cautious of fallen power lines, weakened structures, and contaminated water.
6. How does naming a cyclone help in managing its consequences?
Naming a cyclone is a critical part of disaster management. Giving a cyclone a unique and memorable name helps in clear communication and raises awareness. It makes it easier for the media, disaster management agencies, and the general public to identify and track a specific storm, especially when multiple weather systems are active. This clarity helps prevent confusion and ensures that warnings and safety information are disseminated effectively, thereby reducing the potential for destruction and loss of life.
7. What is the difference between the impact of a cyclone on a coastal area versus an inland area?
The impact of a cyclone differs significantly between coastal and inland areas. Coastal areas bear the brunt of the destruction, facing the combined threat of ferocious winds, torrential rain, and the deadly storm surge, which causes the most significant flooding and property damage right at the point of landfall. As the cyclone moves inland, it weakens because it is cut off from its energy source—the warm ocean water. While the wind speeds decrease, the system can still dump enormous amounts of rain, leading to severe riverine flooding in inland regions, often many kilometres away from the coast.
