Cyclones are caused by atmospheric disturbances around a low-pressure area distinguished by swift and often destructive air circulation. Cyclones are usually accompanied by violent storms and bad weather. The air circulates inward in an anticlockwise direction in the Northern hemisphere and clockwise in the Southern hemisphere.
- Cyclones are classified as: (i) extra tropical cyclones (also called temperate cyclones); and (ii) tropical cyclones.
- The word Cyclone is derived from the Greek word Cyclos meaning the coils of a snake. It was coined by Henry Peddington because the tropical storms in the Bay of Bengal and the Arabian Sea appear like coiled serpents of the sea.
Hazards associated with Cyclones
There are three hazards associated with a cyclone, which cause destruction
- Human loss: Cyclones, which are responsible for much loss of life, damage to property and deterioration of day-to-day life.
- Economic impact: Impacts of cyclones cause direct economic losses such as loss in asset value, and reduction in investments which is a socioeconomic impact of a disaster.
- Food scarcity: Food scarcity is the main impact of cyclones as they lose their agricultural supplies.
- Livelihood: Cyclones mostly affect coastal districts. Several people in coastal villages who depended only on fishing had lost access to food and clean drinking water as fishing was prohibited.
- Structural damage: Damage to infrastructures such as roads, bridges, and revetment results in loss to both the public and the Government.
- Floods: Cyclones may result in heavy rainfall and floods which is the next devastation to the environment. Floods caused by the cyclone can cause waterlogging in unwanted places which causes many diseases.
- Agricultural damage: Devastation of crops may result in reduced income for farmers, increased prices for food,
unemployment, and increased crimes which in turn human populations are at higher level of risk.
- Sea level: Abnormal rise in sea level caused by cyclones is known as storm surge.
- Inequality: The impact of a natural disaster may also cause inequalities. The people whose income is below the poverty threshold or people with low-income , who suffer from income.
fluctuations, and also have limited access to financial services, in the aftermath of a disaster, may be more prone to
Most destructive cyclone in the past
- 1942 Bengal Cyclone: hit near the India/Bangladesh border, resulting in around 40,000 fatalities.
- 1971 Orissa Cyclone: killed around 10,000people in Cuttack, Orissa, India.
- 1977 Andhra Pradesh Cyclone: killed 10,000people in Andhra Pradesh, India.
Mitigation measures for Tropical cyclone
Hazard mitigation for cyclone as follows :
- Hazard mapping
- Land use planning
- Engineered structures
- Retrofitting Non-engineered Structures
- Cyclone Shelters
- Flood management
- Improving vegetation cover
- Saline embankments
- Raised embankment or levees
FAQs (Frequently Asked Questions) about Tropical Cyclones and Their Related Hazards
Q 1. What is a tropical cyclone?
Ans. A tropical cyclone is a rotating low-pressure weather system that forms over warm ocean waters near the equator. It is characterizes by strong winds, heavy rainfall, and thunderstorms. Tropical cyclones are known as hurricanes (Atlantic and eastern Pacific), typhoons (western Pacific), or cyclones (Indian Ocean and southern Pacific) depending on their location.
Q2. How do tropical cyclones form?
Ans. Tropical cyclones form over warm ocean waters (typically with a sea surface temperature of at least 26.5°C or 80°F) when atmospheric conditions are favorable. Warm, moist air rises from the ocean surface, creating an area of low pressure. As the warm air rises, it cools and condenses, releasing latent heat and further fueling the storm’s development. If the storm gains sufficient rotation and sustained winds, it becomes a tropical cyclone.
Q3. What are the hazards associated with tropical cyclones?
Ans. Tropical cyclones pose several hazards, including:
- High Winds: Destructive winds can cause extensive damage to buildings, trees, and infrastructure.
- Storm Surges: Tropical cyclones can push seawater toward the coast, leading to significant coastal flooding.
- Heavy Rainfall and Flooding: Intense rainfall can cause flash flooding and landslides, even far from the storm’s center.
- Tornadoes: Tropical cyclones may spawn tornadoes, adding to the overall threat.
- Ocean Waves: Large waves generated by cyclones can lead to coastal erosion and additional flooding.
Q4. How are tropical cyclones classified and named?
Ans. Tropical cyclones are classified based on their maximum sustained wind speeds using various scales (e.g., Saffir-Simpson scale for hurricanes). As for naming, different regions have different naming systems. Meteorological organizations around the world assign names to tropical cyclones to aid in communication and public awareness. The names are usually predetermines from a list specific to each region.
Q5. What safety measures should be taken during a tropical cyclone?
Ans. To stay safe during a tropical cyclone, it’s essential to follow these guidelines:
- Stay Informed: Keep track of weather updates and warnings issued by local authorities and meteorological agencies.
- Evacuation: If you live in a vulnerable area, follow evacuation orders promptly.
- Secure Property: Secure loose objects, windows, and doors to minimize damage from high winds.
- Avoid Flooded Areas: Stay away from flooded streets and avoid crossing flooded rivers or streams on foot or by vehicle.
- Emergency Kit: Prepare an emergency kit with essentials such as water, food, first aid supplies, and flashlights in case of power outages.
Tropical Cyclones And Their Related Hazards,Tropical Cyclones And Their Related Hazards