| A | B |
| environment | everything that surrounds an organism |
| oceanography | scientific study of the ocean |
| limnology | scientific study of inland fresh water bodies |
| hydrosphere | the water portion of the Earth |
| organism | any living thing |
| oceans | cover 71% of the Earth |
| percent of salt water on Earth by volume | 97% |
| percent of freshwater on Earth by volume | 3% |
| percent of freshwater locked up in ice caps, glaciers, or too deep | 2.997% |
| percent of available freshwater for use | 0.003% |
| geosphere | the land of the Earth |
| Hydrologic Cycle | water cycle |
| evaporation | the movement of water into the atmosphere as it changes from a liquid to a gas |
| transpiration | the loss of water vapor by plants |
| evapotranspiration | the loss of water by evaporation and transpiration |
| condensation | changing from a gas to a liquid state |
| precipitation | moisture that falls from the atmosphere |
| infiltration | the downward entry of water into the soil |
| runoff | excess precipitation over evaporation that runs over the land into streams, lakes, wetlands, and reservoirs and is the main source of surface water |
| watershed | (also called a drainage basin) - the surface area or region from which water drains into a stream, river, lake, reservoir, or other water body |
| groundwater | water that seeps down through the soil, fills voids in the soil and rock and is stored underground |
| water table | the boundary between the unsaturated upper layer of soil and the saturated layer beneath |
| surrounded by an impervious layer below and above | aquifer |