| A | B |
|---|
| weather patterns | changes in weather are caused by movements of air masses |
| air masses | large bodies of air (1000s km2) that are uniform in properties: temperature, humidity |
| "tropical" | warm |
| "polar" | cold |
| maritime | these winds form over ocean - moist |
| continental | these winds form over land - dry |
| cold front | cold air pushes under warm air; violent storms followed by fair, cool weather |
| front | boundary where 2 DIFFERENT air masses meet |
| warm front | warm air overtakes cold air; rain/showers; hot and humid weather follows |
| occluded front | fast moving cold front overtakes a warm front or cool air overtakes a cold front; either way warm air moves up; produces less extreme weather |
| stationary front | neither air mass is moving; rain can last for days |
| storms | violent disturbance in the atmosphere; small or large area |
| rainstorms and snowstorms | this type of storm occurs when warm front meets cold front; nimbostratus clouds; |
| thunderstorms | this type of storm occurs when cold front meets warm front |
| cyclone | this type of storm occurs when an area of low pressure that contains rising warm air; cool air replaces warm and starts to spin (NA counterclockwise) |
| hurricane | type of cyclone has a calm eye; winds up to 250 mph; warm and moist |
| tornado | this type of cyclone is usually found over land; it is a low pressure vacuum |
| Anticyclone | this type of cyclone has the opposite spin and pressure than "normal hemispheric" cyclones |
