Prelims Perspective: What needs to be learned?

• Bomb Cyclone
• Tropical Cyclone 

Mains Perspective: Notes need to be prepared

• Climatology (GS I- Geography)
• Classification of Disaster (GS III – Disaster Management)

What needs to be known?

• Bomb Cyclone
  • What is it?: 
    • A bomb cyclone is a large, intense midlatitude storm that has low pressure at its center, weather fronts and an array of associated weather, from blizzards to severe thunderstorms to heavy precipitation.
    • This process is called explosive cyclogenesis or bombogenesis.
  • Conditions for Formation
    • Strong temperature contrast (cold polar air meets warm tropical air)
    • Upper-level jet stream support (divergence aloft)
    • Warm ocean currents (e.g., Gulf Stream, Kuroshio) providing latent heat
    • Pre-existing low-pressure system
  • Areas of Formations
    • North Atlantic Ocean (eastern coast of USA, Europe)
    • North Pacific Ocean (Japan, Alaska)
    • Southern Ocean (around Antarctica)
• Tropical Cyclone
  • What is it?: A cyclone is a large-scale air system rotating around a low-pressure centre, accompanied by high winds and rainfall.
  • Conditions for Formation
    • Sea surface temperature > 26°C
    • High humidity in the troposphere
    • Low vertical wind shear
    • Pre-existing low-pressure area
  • Direction
    • Anticlockwise in the Northern Hemisphere.
    • Clockwise in the Southern Hemisphere.
  • Areas of Formations
    • Hurricanes (Atlantic and Northeast Pacific),
    • Typhoons (Northwest Pacific),
    • Tropical Cyclones (Indian Ocean & South Pacific).

Source: The Indian Express