What is Bomb Cyclone?
- Storms can form when a mass of low-pressure air meets a high-pressure mass. The air flows from high pressure to low, creating winds.
- What defines a bomb cyclone is how rapidly the pressure drops in the low-pressure mass — by at least 24 millibars in 24 hours. This quickly increases the pressure difference, or gradient, between the two air masses, making the winds stronger. This process of rapid intensification has a name: bombogenesis.
- As the winds blow, the rotation of the Earth creates a cyclonic effect. The direction is counterclockwise in the Northern Hemisphere (when viewed from above).
- As the area where the two air masses meet, called the Arctic front, moves northward and eastward, conditions for bombogenesis should continue moving as well.
- But as the Arctic air spreads over most of the country it will eventually warm, reducing the pressure difference. The storm will dissipate.
Why in News?
- Bomb cyclone enveloped much of the US recently.