| A | B |
|---|
| air mass | a body of air with about the same temperature and moisture. Air masses may form over land or water and take on the properties fo the surfaces they form over |
| air pressure | the pressure exerted in all directions by air pressing on an object |
| atmosphere | a blanket of air that surrounds and protects Earth |
| condensation | the change of a gas to a liquid of solid |
| dense | having parts closely packed together |
| evaporation | the change of a liquid to a gas |
| front | the boundary between two air masses of different temperature |
| global warming | a rise in Earth's average temperature |
| precipitation | any form of water that falls to Earth |
| transpiration | the process by which plants transfer water vapor to the atmosphere |
| water cycle | the continuous movement of water in the environment through evaporation, condensation, and precipitation |
| climate | the typical weather conditions of a particular place over a long period of time |
| weather | the day to day conditions in the atmosphere, such as temperature, wind speed and direction, precipitation, humidity, and air pressure. |
| cloud | a mass of water droplets and/or ice particles floating in the air |
| anemometer | weather instrument that measures wind speed |
| barometer | instrument for measuring air pressure |
| meteorologist | a scientist who studies the weather |
| polar climate | cold climates that occur in regions that don't receive sunlight as directly as the tropical zone |
| tropical climate | warm or hot year-round climates occurring in places closest to the equator |
| temperate climate | occurs in places that are between the equator and the poles where the weather is warmer than the poles, but cooler than the tropics |
| troposphere | the layer of Earth's atmosphere that is closest to Earth and contains the air and water that living things need to survive. |
| stratosphere | The layer of Earth's atmosphere right above the troposphere containing the ozone layer which obsorbs ultraviolet rays from the sun |
| mesosphere | The layer between 50 and 80 km above Earth's surface |
| thermosphere | Contains the two outermost layers of Earth's atmosphere - the ionosphere and the exosphere. |
| rain shadow | a dry area on the downward side of a mountain |
