Water Cycle
5th grade, 6th grade, 7th grade, 8th grade, Middle School.
Water Cycle : The water cycle is the process by which water evaporates, forms clouds, and falls back to the surface as precipitation, before flowing back to the oceans, rivers, lakes, and underground reservoirs. It is powered by the sun and is a critical process for the distribution of freshwater and supporting life on earth.
Evaporation is the process by which water changes from a liquid to a gaseous state through the action of heat or solar radiation. Water molecules absorb energy and break free from the surface, rising into the atmosphere and eventually condensing into clouds. It occurs from all bodies of water and is a crucial part of the water cycle.
Condensation is the process by which water vapor cools and returns to its liquid state, forming clouds or dew. Water molecules lose energy and stick together to form droplets that can collect on surfaces or remain suspended in the air as clouds. This is crucial to the water cycle and is the mechanism by which water is returned to the surface as precipitation. Without condensation, the water cycle would not be able to continue.
Precipitation refers to any form of moisture that falls from the atmosphere and reaches the Earth's surface, such as rain, snow, sleet, or hail. It occurs when water vapor in the air condenses and becomes heavy enough to fall back to the surface. Precipitation is a critical component of the water cycle and helps to replenish freshwater supplies and sustain ecosystems and human activities.
Surface runoff is the movement of water across the surface of the Earth as a result of precipitation. It flows over the surface until it reaches a river, lake, or ocean, and can pick up pollutants, sediments, and nutrients along the way. Surface runoff is important for transporting water and replenishing freshwater supplies, but excessive runoff can have negative environmental impacts and cause damage to ecosystems and infrastructure.
