The hydrologic cycle, also known as the water cycle, describes the continuous movement of water on, above, and below the Earth’s surface through various processes. It includes evaporation, where water from oceans, lakes, and soil turns into water vapor due to solar energy; transpiration, where plants release water vapor into the atmosphere; condensation, where water vapor cools and forms clouds; precipitation, which returns water to the surface as rain, snow, or other forms; infiltration, where water seeps into the soil; and runoff, the movement of water over land into rivers, lakes, and ultimately the oceans. This cycle is essential for distributing fresh water, sustaining ecosystems, and regulating climate. Although the total amount of water on Earth remains fairly constant, its state and location are constantly changing, driven primarily by solar energy.
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