In this topic, you will learn how the water cycle affects you every day.

Water on the surface of Earth is heated by the Sun. Heat energy from the Sun causes the particles of water at the surface to move rapidly. As they absorb heat energy, these moving water particles go through the process of evaporation. Evaporation means that the particles change from a liquid to a gas. The gas, known as water vapor, is invisible and rises into the atmosphere.

Particles of water move slowly high in the atmosphere because it is very cold. These water particles lose heat energy, slow down, and condense. Condensation means a change from a gas to a liquid.

Tiny droplets of condensed water in the atmosphere form clouds. Clouds are tiny drops of condensed water in the atmosphere. When droplets of water in clouds come together, they get bigger and heavier. Gravity causes the heavy droplets to fall.

Water in the atmosphere that falls to Earth as rain, snow, hail, or sleet is called precipitation. The form in which precipitation falls depends on temperature. Most of the precipitation falls into the oceans, lakes, and rivers. When rainfall is heavy, water will flow over land into rivers. Some water also soaks into the ground to become soil water or groundwater.

Cold temperatures cause water to release heat energy, or lose heat. When this happens, the moving particles in water slow down and may freeze or the particles change from a liquid to a solid. Ice and snow are solid water. When solid water particles absorb energy, ice and snow melt or change from a solid to a liquid.

Water does not stay put. It moves continuously from place to place. The movement of Earth's water through evaporation, condensation, and precipitation is called the water cycle.

Precipitation falls from the atmosphere in many different forms. Rain falls as a liquid. Snow, sleet, and hail are solids. Snow falls in the form of crystals, and sleet and hail are frozen raindrops.

The water cycle affects everyone on Earth. Knowing about the water cycle and precipitation helps people know about clouds and weather. The water cycle is nature's way of recycling its resources.