The well known Polar-front theory was described by the Bergen school early 20th century. The theory explains the formation, development and life cyles of cyclones. In short several stages of cyclone development can seperately be identified.
- Development of a Front (known as frontogenesis).
- A Wave develops on the front.
- A cyclonic circulation (area of low pressure) becomes established.
- The cold front overtakes the warm front, initial stage of an occlusion.
- The development of the occluded front continues and the cyclone reaches its mature stage.
- The lifetime of a cyclone is about 3 to 5 days from the initial wave to the dissipating stage.
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The lifecycle of a cyclone |
In the above Figure 1 this lifecycle is graphically represented with the development of the Wave (A). Second the cyclonic circulation and the establishment of a low pressure area (B). In the third image (C) the cold front overtakes the warm front and an occlusion-front is formed. Lastly, the development of the occlusion continues and the cyclone has reached its mature stage (D).
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