| A | B |
|---|
| hydrocarbons in which some or all of the hydrogen atoms are replaced by chlorine and fluorine; used in coolants for refrigerators and air conditioners and in cleaning solvents; they were thought to be miracle chemicals because they were nonpoisonous, nonflammable, and did not corrode metals | chlorofluorocarbons |
| the average weather conditions in an area over a long period of time | climate |
| the short term periodic change in the location of warm and cold water masses in the Pacific Ocean; the warming period that lasts 6-18 months | El Nino |
| a gradual increase in the average global temperature that is due to a higher concentration of gases such as carbon dioxide in the atmosphere | global warming |
| a gas composed of molecules that absorb and radiate infrared radiation from the sun; water vapor, carbon dioxide, CFCs, methane, and nitrous oxide | greenhouse gas |
| a treaty from 1997 that requires developed nations to decrease emissions of carbon dioxide and other greenhouse gases by an average of 5% below their 1990 levels by 2012; the U.S. did not ratify this is 2001 | Kyoto Protocol |
| the short term periodic change in the location of cold water masses in the Pacific Ocean; the cooling period of 6-18 months | La Nina |
| the distance north or south of the equator; expressed in degrees | latitude |
| a thinning of the stratospheric ozone that occurs over the poles during the spring | ozone hole |
| the layer of atmosphere at an altitude of 15 to 40 km in which ozone absorbs ultraviolet solar radiation; the area of the stratosphere where ozone is highly concentrated | ozone layer |
| a cloud that forms at altitudes of 21,000 m during the arctic and antarctic winter or early spring; when air temperatures drop below -80 degrees celcius | polar stratospheric clouds |
| the short-term state of the atmosphere, including temperature, humidity, precipitation, wind and visibility | weather |
