| A | B |
|---|
| climate | average weather patterns over a period of many years |
| delta | A large, triangular deposit of sediment at the mouth of a river |
| ecosystem | A community of plants and animals that live together in the same environment and depend on each other for survival |
| estuary | An area where freshwater and saltwater mix at the mouth of a river |
| glacier | A huge, slow-moving mass of ice and snow |
| natural resource | Any material found in the environment that is useful to humans |
| non-renewable resource | Minerals and fossil fuels, including coal, petroleum, and natural gas, that can be used once and cannot be replaced |
| recyclable resource | A natural resource that can be reused after cycling through a renewing process |
| renewable resource | A natural resource that continues to supply or replace itself |
| tectonic plates | Large sections of the Earth’s crust that move against one another, generating volcanoes and earthquakes |
| terrain | The physical features of a region |
| topography | A description of the surface features of a region, both natural and man-made |
| tributary | A smaller river that flow into a larger river |
| weather | A description of the atmosphere’s temperature, humidity, wind, and pressure on a daily basis |
| wetland | Areas of land, such as tidal areas or swamps, where much of the soil is covered with water |
