| A | B |
|---|
| Celcius | temperature scale in which water boils at 100º C and freezes at 0º C |
| water vapor | water in the form of an invisible gas |
| humidity | the amount of water vapor in the air |
| evaporate | to change from a liquid to a gas |
| condense | to change from a gas to a liquid |
| precipitation | any form of water that falls to the earth from a cloud |
| runoff | water that falls onto land and drains off the surface |
| climate | the average weather conditions in an area over many years |
| infrared radiation | energy with a wavelength longer than the wavelength of light |
| greenhouse gases | carbon dioxide, water vapor, and other gases in the atmosphere that absorb infrared radiation from the earth's surface |
| greenhouse effect | the process by which gases in the atmosphere absorb heat and keep the earth warm |
| global warming | an increase in the earth's temperature |
