| A | B |
|---|
| atmosphere | layer of gases around the planet |
| weather | the condition of Earth's atmosphere at a particular time and place |
| ozone | form of oxygen that has three oxygen atoms in each molecule |
| water vapor | water in the form of a gas |
| air pollution | change to the atmopshere that has harmful effects |
| emissions | solid particles and gases released into the air |
| photochemical smog | thick, brownish haze formed when certain gases in the air react with sunlight |
| temperature inversion | layer of warm air prevents the rising air from escaping |
| acid rain | precipitatino that is more acidic than normal |
| ozone layer | layer of the upper atmosphere |
| chlorofluorocarbons | group of gases containing chlorine and fluorine once used in refrigerators and air conditioners |
| greenhouse effect | trapping of heat near Earth's surface |
| global warming | prediction that increasing carbon dioxide will cause the average temperatures on Earth to rise |
| pressure | force pushing on an area or surface |
| density | amount of mass in a given volume |
| air pressure | result of the weight of a column of air pushing down on an area |
| barometer | instrument used to measure changes in air pressure |
| mercury barometer | glass tube open at the bottom end and partially filld with mercury |
| aneroid barometer | airtight metal chamber |
| altitude | distance above sea level |
| aurora borealis | brilliant light displays occuring in the ionosphere |
