Hydrologic Cycle Source: EPA Six components of the Hydrologic Cycle:

• Evapotranspiration - is water evaporating from the ground and transpiration by plants. evapotranspiration is also the way that water vapor re-enters the atmosphere.
• Condensation - is the process of water changing from a vapor to a liquid. Water vapor in the air rises mostly by convection. This means that warm, humid air will rise, while cooler air will flow downward. As the warmer air rises, the water vapor will lose energy, causing its temperature to drop. The water vapor then has a change of state into liquid or ice.
• Precipitation - is water being released from clouds as rain, sleet, snow or hail. Precipitation begins after water vapor, which has condensed in the atmosphere, becomes too heavy to remain in atmospheric air currents and falls.
• Infiltration - when a portion of the precipitation that reaches the Earth's surface seeps into the ground.
• Percolation - is the downward movement of water through soil and rock. Percolation occurs beneath the root zone.
• Runoff - is precipitation that reaches the surface of the Earth but does not infiltrate the soil. Runoff can also come from melted snow and ice.

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