Home > Encyclopedia of Science > Wind

• The Coriolis effect and wind direction
• Words to Know
• Friction and wind movement
• Local winds
• Wind chill
• Wind shear

Wind refers to any flow of air above Earth's surface in a roughly horizontal direction. A wind is always named according to the direction from which it blows. For example, a wind blowing from west to east is a west wind.

The ultimate cause of Earth's winds is solar energy. When sunlight strikes Earth's surface, it heats that surface differently. Newly turned soil, for example, absorbs more heat than does snow. Uneven heating of Earth's surface, in turn, causes differences in air pressure at various locations. Heated air rises, creating an area of low pressure beneath. Cooler...