Weather and Climate

Weather is what the sky is doing right now — sunny, rainy, windy, or snowy. Climate is the usual weather a place gets over many years. Here is an easy way to remember the difference: weather is what you decide to wear today, while climate is the kind of clothes you keep in your wardrobe all year round.

Almost all weather is powered by the Sun. The Sun heats the air and the seas, but it does not heat them evenly. Warm air is lighter, so it rises; cooler air is heavier, so it sinks to take its place. This constant movement of air is what we feel as wind. Without the Sun, there would be no wind, no clouds, and no weather at all.

Clouds form when warm, damp air rises and cools. As it cools, the invisible water vapour in it turns back into tiny droplets, and millions of these droplets together make a cloud. When the droplets join up and grow too heavy to float, they fall to the ground. If the air is warm they fall as rain; if it is freezing cold they fall as snow or hail.

People who study and predict the weather are called meteorologists. They gather information from weather stations, balloons, satellites, and radar, then use powerful computers to make a forecast. A good forecast helps farmers plan their crops, pilots fly safely, and all of us decide whether to pack an umbrella.

Some weather can be wild! Thunderstorms crackle with lightning, and spinning storms called hurricanes whirl with powerful winds and heavy rain. A common mix-up is thinking thunder and lightning are two separate events — in fact thunder is simply the sound that the lightning makes as it suddenly heats the air around it.