WATER (HYDROLOGIC) CYCLE
Water is essential for life on earth. It is recycled through the water or hydrologic cycle, which involves the following processes:
- Accumulation - the process in which water pools in large bodies (like oceans, seas and lakes).
- Evaporation - the process in which liquid water becomes water vapor (a gas). Water vaporizes from the surfaces of oceans, lakes, land, and from snow that melts in fields.
- Condensation - the process in which water vapor (a gas) in the air turns into liquid water. Condensing water forms clouds in the sky. Water drops that form on the outside of a glass of icy water are condensed water
- Infiltration - the process of water filling the porous spaces of soil
- Percolation - groundwater moving in the saturated zone below the earth's surface
- Precipitation - the process by which water molecules condense to form drops heavy enough to fall to the earth's surface
- Sublimation - the changing of water from a solid to a gas
- Subsurface Runoff - rain, snow melt, or other water that flows in underground streams,
- Surface runoff - the flowing of water over the land from higher to lower ground rain, snow melt, or other water that flows in surface streams, rivers, or canals.
- Transpiration - the process in which some water within plants evaporates into the atmosphere. Water is first absorbed by the plant's roots, then later exits by evaporating through pores in the plant.