Final answer:
The water cycle is a critical, sun-driven process where water moves continuously through various forms and reservoirs on Earth, essential for sustaining life and ecosystems.
Step-by-step explanation:
The water cycle, also known as the hydrological cycle, is essential to all life on Earth. Powered by the sun's energy, this continuous process involves the movement of water through various reservoirs including oceans, the atmosphere, glaciers, groundwater, and the biosphere. Water takes on different forms throughout the cycle, existing as a liquid, solid (ice), or gas (water vapor).
Solar energy causes the evaporation of water from the Earth's surface and the sublimation of ice, contributing water vapor to the atmosphere. Condensation of this vapor forms clouds, which lead to precipitation (rain or snow), returning water to the land and oceans. Earth's gravity drives the flow of water, through surface runoff, streams, and rivers, back to the oceans, completing the cycle.
Whether it is seeping underground to become groundwater, flowing as surface runoff, or being taken up by plants and returned to the atmosphere through transpiration, the water cycle is a complex but seamless engine that sustains ecosystems. It is a critical component of Earth's system, maintaining the water supply for all organisms and environments.