The Power of Wind

The Power of Wind

The First Sailor More than five thousand years ago, a person took cloth and attached it to the mast of a boat. The wind caught the sail. It pushed the ship forward, sending it across the water. For the first time, people had harnessed the power of wind. It was just the beginning. Today, we use wind to power just about everything, from computers to cars.

What Is Wind? The wind can be our friend. It cools us off on hot summer days and allows us to fly kites high in the sky. The wind can also cause great damage, downing power lines, trees, and even buildings. This moving air is mainly caused by differences in air pressure, which in turn are due to differences in temperature. Warm air rises and spreads out. This is known as low pressure. Cold air, on the other hand, sinks and compresses. This is known as high pressure. Air moves from areas of high pressure to areas of low pressure across the planet. This creates wind.

The air in a balloon, for example, is under higher pressure than the air outside it. When you let air out of a balloon, the air rushes out into the area of lower pressure. That's wind! Areas of high and low pressure are always moving and changing as Earth spins and moves around the Sun. Usually, the greater the difference in pressure between two areas, the faster the wind blows.

Sailboats Sailboats were the first important use of wind power. Early sailboats were simple ships with a single sail. Wind power only helped people travel in one direction-the direction the wind was blowing. In time, people learned to use sailboats to travel against the wind. They built ships with many sails that could travel long distances. People used sailboats for fishing, trading, exploration, and war. Sails powered the battleships of ancient Greece. They helped the Vikings travel to Europe, Africa, and North America.

In the 1500s, explorers used massive ships with sails to travel the globe. People coming to the Americas also used these types of ships. In time, engines replaced sails as the main way to power ships. Today, people still sail for fun.