Typhoon

• A typhoon is a type of tropical cyclone, which is a large, rotating storm system that forms over warm ocean waters in the Western Pacific Ocean. Typhoons are characterized by strong winds, heavy rainfall, and sometimes storm surges or flooding.
• 1. Formation

  • Warm Ocean Water: Typhoons form over warm ocean waters, typically with surface temperatures of at least 26°C (79°F).

  • Low Pressure System: A typhoon begins as a low-pressure area in the atmosphere. Warm, moist air rises from the ocean, causing the air pressure to drop, which creates a feedback loop where more air rushes in and rises, fueling the storm.

  • Coriolis Effect: The rotation of the Earth causes the typhoon to spin, giving it the characteristic rotating structure.
• Structure

  • Eye: The calm, clear center of the storm, usually 20-40 km in diameter. Winds are light and skies are relatively clear within the eye.

  • Eyewall: Surrounding the eye, the eyewall is the region of the strongest winds and heaviest rainfall.

  • Rainbands: Spiral bands of rain and thunderstorms extending outward from the center of the typhoon, contributing to intense rainfall and gusty winds.
• Categories

  Typhoons are categorized based on wind speed. The Saffir-Simpson Hurricane Wind Scale is often used, with wind speeds increasing in severity from Category 1 (mild) to Category 5 (extreme).
• Wind Speeds

  • Tropical Depression: Wind speeds below 63 km/h (39 mph).

  • Tropical Storm: Wind speeds between 63-118 km/h (39-73 mph).

  • Typhoon: Wind speeds exceeding 118 km/h (73 mph).

  • Super Typhoon: Wind speeds exceeding 240 km/h (150 mph).
• Impacts

  • Strong Winds: Can cause widespread damage to buildings, infrastructure, and vegetation.

  • Heavy Rainfall: Leads to flooding, landslides, and other water-related hazards.

  • Storm Surge: Rising sea levels caused by strong winds pushing water toward the coast, often resulting in coastal flooding.
• Regions

  • Typhoons occur primarily in the Western Pacific Ocean and affect countries like the Philippines, Japan, China, and Taiwan.

  • In the Atlantic and Eastern Pacific, these storms are called hurricanes, while in the Indian Ocean, they are referred to as cyclones.