What processes produce the selected extreme natural event? How often does it occur?
Cyclones start when strong clusters of winds drift over warm ocean waters.
The warm air from the storm and ocean surface combine and begin rising. This creates low pressure at the surface. Winds start blowing in the opposie direction causing the storm to start spinning.
ocean it picks up more warm, moist air. Wind speeds start to increase as more air is sucked into the low pressure centre.
How often do Tropical Cyclones occur?
In the northern hemisphere, tropical cyclones occur mainly between June and November in the North Atlantic, the North Pacific and the North Indian Ocean. In the southern hemisphere, they occur mainly between November and April in the South Indian Ocean, the South Pacific Ocean and in the seas around northern Australia.
The region shaded red is where tropical cyclones occur.