As the sun heats the ground it simultaneously warms the adjacent air causing it to become less dense. The cooler air then rushes in to fill the empty space causing the warm air to rise. As the rising air reaches the sky it cools down and the water vapor condenses and formulates cumulus clouds.
As the air to rises, hang gliders mimic soaring birds and use air currents to elevate themselves into the sky. The wind flows through mountain ranges like water over rocks in a river.
