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Weather Patterns123
Question | Answer |
---|---|
a huge body of air that has similar temperature humidity,and air pressure at any given height. | Air Mass |
4 major types of air masses influence the weather in North America | maritime tropical,continental tropical,maritime polar,and continental polar |
tropical or warm air masses form | in the tropics,and has low air pressure |
polar or cold air masses from | north of 50 degrees north latidude and south of 50 degrees south latidude with high air pressure |
maritime air masses form | over oceans |
continental air masses form | over land |
warm humid air masses form over the Gulf of Mexico and Atlantic Oceans | maritime tropical |
cool, humid air masses form over the icy cold North Pacific and North Atlantic oceans | maritime polar |
hot, dry air masses form mostly in summer over dry areas of the Southwest and northern Mexico | continental tropic |
form over central and northern Canada and Alaska, bring bitterly cold weather with very low humidity | continental polar |
air masses are commonly moved by the prevailing westerlies and jet streams. | in the united states |
major wind belt over the continental United States pushing air masses from west to east. | prevailing westerlies |
bands of high-speed winds about 10 kilometers above Earth's surface, blow from west to east carrying air masses | jet streams |
When two different air masses collide, the warmer, less dense will go on top with the cooler, denser going on bottom. These air masses do not mix well. The boundary where the air masses meet becomes a front. | fronts |
four types of fronts: cold fronts, warm fronts, stationary fronts, and occluded fronts. | colliding air masses can form |
When a rapidly moving cold air mass runs into a slowly moving warm air mass, the denser cold air slides under the lighter warm air. The warm air is pushed upward along the edge of the colder air and forms a cold front. | cold front |
a fast moving warm air mass overtakes a slower moving cold air mass. If the warm air is humid, light rain or snow could fall. If the warm air is dry, scattered clouds form. | warm front |
Sometimes cold and warm air masses meet, but neither one will move and face each other in a "standoff". This is called a stationary front because it will not move and may bring days of clouds and precipitation. | stationary front |
a warm air mass is caught between to cold air masses. The two cooler air masses meet in the middle and push the less dense warm air mass upward. This will result in cooler temperature. | occluded fronts |
a swirling center of low pressure | cyclones |
high pressure centers of dry air; winds spiral outward from the high-pressure center of an anticyclone. High pressure systems are marked with an H. The descending air in an anticyclone generally causes dry, clear weather. | anticyclones |
NOW STARTING SECTION 2 | REMEMBER TO FIND KEY-WORDS (YOU DONT ALWAYS HAVE TO MEMORIZE THE WHOLE DEFINITION) |
violent disturbance in the atmosphere; conditions that bring one kind of storm, often cause other types of storms (thunderstorms cans bring tornadoes). | storm |
a small storm often accompanied by heavy precipitation and frequent thunder and lightning, forms in large cumulonimbus clouds also known as thunderheads. | thunderstorms |
lightning is a sudden spark, or electrical discharge that rapidly heats the air causing it to expand suddenly and explosively. The explosion is the thunder, since light can travel faster than sound; you see the lightning first and then hear the thunder | lightning & thunder |
occur when so much water pours into a river or stream that its banks overflow, covering the surrounding land. | floods |
avoids places where lightning may strike, objects that conduct electricity, and bodies of water. | thunderstorm safety |
one of the most destructive types of storms, rapidly whirling, funnel-shaped cloud that reaches down from a storm cloud to touch the Earth's surface, can be brief and last for 15 minutes or less and leave a path only a few 100 meters across | tornado |
Tornadoes that occur over a lake or ocean are called | water-spout |
notes... | Tornadoes most commonly form in thick cumulonimbus clouds. |