Bonnie Hill, age 10, of St. Cathrines, Ont.

What causes cyclones?

We can blame the cyclones on the sun. For the sun causes the huge cyclones that can cover a whole continent, the howling hurricanes and the furious little tornados. All these storms are cyclones.

The sun heats up the surface of the world in irregular patches. The air is heated by the earth and ocean below it. The air over the warm spots forms pockets of warm air surrounded by cooler air. This kind of situation is what starts a cyclone.

The warm air expands and rises, leaving a pocket of thinner air in the midst of surrounding cooler air. The cooler, heavier air pours in to fill up the weaker spot. Winds blow towards the center, and the cyclone is underway.

The spinning earth gives a twist to the winds and sets them going round in a spiral. The swirling cyclone moves off tin the prevailing winds. A big cyclone may travel right around the world, changing as it goes. Smaller cyclones tend to be more fierce, but they blow themselves out in a few days or even a few hours.