What is the water cycle?

The water cycle refers to the continuous movement of water within the Earth and atmosphere. This cycle includes processes such as evaporation, where water transforms from liquid to vapor and ascends into the atmosphere, and precipitation, where water returns to the Earth's surface in various forms, including rain, snow, sleet, or hail. This natural cycle is vital for replenishing water sources, supporting ecosystems, and regulating climate.

Understanding the water cycle is crucial for environmental health specialists as it directly impacts water availability, quality, and management in both natural and built environments. In contrast, the other options focus on specific activities related to water, such as treatment, storage, or diversion, rather than describing the overarching process that sustains all these activities and maintains the balance of ecosystems.