| A | B |
|---|
| 70 | % of the Earth’s surface is covered with water |
| 97 | % of the water on Earth that is salt water |
| 3 | % of the water on Earth that is freshwater |
| .5 | % of the water on Earth that is usable |
| polar ice cap | the majority of freshwater is trapped here |
| hydrologic cycle | the continuous movement of water that renews our freshwater supply |
| Evaporation | water changes from a liquid to gas |
| transpiration | evaporation done by plants |
| Condensation | water changes from a gas back to a liquid |
| precipitation | water falls to the Earth |
| reservoir | a man-made lake built by damming a stream or river |
| Erosion | weathered rock and soil particles are moved from one place to another |
| deposition | sediments are laid down in new locations |
| pore space | spaces between soil particles |
| permeable | Material through which water can easily move |
| impermeable | Material through which water cannot pass |
| zone of saturation | all pores are filled with water |
| zone of aeration | all pores are filled with air |
| water table | The boundary between the zone of saturation and the zone of aeration |
| aquifer | an underground pool where water collects |
| Hard water | water that contains dissolved minerals |
| Soft water | water that does not contain minerals |
| 65 | % of your body that is water |
| Point-source pollution | pollution that comes from a single source |
| Nonpoint-source pollution | pollution that comes from many sources |
