Bomb Cyclone

• 27 Dec 2022

Why in News?

Recently, a Bomb cyclone hit the United States and Canada, which triggered road accidents that results in the death of more than 30 people.

What is a Bomb Cyclone?

• About:
  • 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.
  • Bomb cyclones put forecasters on high alert because they can produce significant harmful impacts.
• Reasons for the Formation:
  • Storms form when a mass of low-pressure air (warm air mass) meets a high-pressure mass (cold air mass). The air flows from high pressure to low, creating winds.
  • It occurs when a midlatitude cyclone rapidly intensifies, dropping at least 24 millibars over 24 hours.
    • A millibar measures atmospheric pressure.
  • This quickly increases the pressure difference, or gradient, between the two air masses, therefore making the winds stronger.
    • The formation of this rapidly strengthening weather system is a process called bombogenesis.

How does a Bomb Cyclone Differ from a Hurricane?

• Hurricanes tend to form in tropical areas and are powered by warm seas. For this reason, they’re most common in summer or early fall, when seawater is warmest.
• Bomb cyclones generally occur during colder months because cyclones occur due to cold and warm air meeting.
  • During the summer, there’s generally not much cold air across the atmosphere; this means a bomb cyclone is much less likely to occur.
• Hurricanes form in tropical waters, while bomb cyclones form over the northwestern Atlantic, northwestern Pacific and sometimes the Mediterranean Sea.

UPSC Civil Services Examination Previous Year Questions (PYQs)

Consider the following statements: (2020)

1. Jet streams occur in the Northern Hemisphere only.
2. Only some cyclones develop an eye.
3. The temperature inside the eye of a cyclone is nearly 10ºC lesser than that of the surroundings.

Which of the statements given above is/are correct?

(a) 1 only
(b) 2 and 3 only
(c) 2 only 
(d) 1 and 3 only

Ans: (c)

Source: IE