The water cycle, also known as the hydrological cycle, is a continuous process that describes the movement of water on, above, and below the surface of the Earth. It explains how water circulates through different phases and locations in the environment. Here’s an overview of how the model explains this phenomenon:
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Evaporation: The cycle begins with the evaporation of water from bodies of water (like oceans, lakes, and rivers) due to the heat from the sun. This process transforms liquid water into water vapor, which rises into the atmosphere.
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Transpiration: Plants also contribute to the water cycle through transpiration. As they absorb water from the soil for photosynthesis, they release water vapor into the air through small openings in their leaves called stomata.
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Condensation: As the water vapor rises, it cools and condenses into tiny water droplets, forming clouds. This transformation from gas to liquid occurs when the air temperature drops below the dew point, and the water vapor loses energy.
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Precipitation: Eventually, the condensed water droplets merge to form larger droplets. When these droplets become heavy enough, they fall back to the Earth as precipitation in the form of rain, snow, sleet, or hail.
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Collection: When precipitation reaches the ground, it gets collected in various forms. Some of it flows over the surface as runoff into rivers and lakes, while some infiltrates into the soil, replenishing groundwater supplies.
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Infiltration and Percolation: Water that seeps into the ground replenishes aquifers and contributes to the groundwater supply. This water can eventually return to surface water bodies or be taken up by plants.
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Runoff: Water that doesn't infiltrate into the ground drains back into oceans, lakes, and rivers, completing the cycle. Rainwater may also flow into storm drains and waterways, eventually reaching larger bodies of water.
The water cycle is driven by solar energy and gravity and is crucial for maintaining life on Earth. It regulates climate, supports ecosystems, and is integral to agriculture and human consumption. The cycle is continuous and can be influenced by various factors, including climate change, land use, and human activities.