Env Science#3 Waster Use

Hydrologic Cycle- The natural process by which water is purified and made fresh through evaporation and precipitation

Rain Shadow- A dry area on the downwind side of a mountain

Residence TIme-  The length of time a component, such an individual water molecule, spends in a specific compartment or location before it moves on through a particular process or cycle.

Groundwater- Water held in gravel deposits or porous rock below the earths surface

Infiltration- The process of water percolation into the soil and the pores and hollows of permeable rocks

Zone of Aeration- Upper soil layers that hold both air and water

Zone of Saturation- Lower soil layers where all spaces are filled with water

Water Table- The top layer of the zone of saturation; undulates according to the surface topography and subsurface structure

Aquifers- Porous, water-bearing layers of sand, gravel, and rock below the earths surface; reservoirs for groundwater

Artesian Well- A pressurized aquifer from which water gushes without being pumped, due to the aquifers intersecting the surface or being penetrated by a pipe or conduit

Recharge Zones- An area where water inflitrates an aquifer

Discharge- The amount of water that passes a fixed point in a given amount of time

Renewable Water Supplies- Annual freshwater surface runoff plus annual infiltration into underground freshwater aquifers that are accessible for human use

Water Scarcity- When annual available freshwater supplies are less than 1000m^3 (264000) per person

Water Stress- A situation when residents of a country dont have enough accessible, high quality water to meet their everyday needs

Withdrawal- A description of the total amount of water taken from a lake, river, or aquifer

Consumption- The fraction of withdrawn water that is lost in transmission or that is evaporated, absorbed, chemically, transformed, or otherwise made unavailable for other purposes as a result of human use

Saltwater Intrusion- Movement of saltwater into freshwater aquifers in coastal areas where groundwater is withdrawn faster than it is replenished.

Subsidence- A settling of the ground surface caused by the collapse of porous formations that result from a withdrawal of large amounts of groundwater, oil, or other underground materials.