Exploring Global Weather Patterns Vocabulary

Global Weather Patterns

• Air mass: a body of air that has about the same temperature and humidity throughout

• mP: Maritime Polar - cold, moist air mass

• mT: Maritime Tropical - warm, moist air mass

• cP: Continental Polar - cold, dry air mass

• Arctic Front: boundary between Arctic air and warmer air

• ​Polar Front: boundary between polar air and warmer air

• Air pressure: measure of the weight of the atmosphere on a given area of the Earth's surface

• Warm Air: associated with high pressure

• Cold Air: associated with low pressure

• Anemometer: instrument used to measure wind speed

Global Weather Patterns

• Atmosphere: An envelope of mixed gases held to the Earth by gravity; the most dense gases are near the surface.

• Convection Current: Temperature differences cause fluids to expand and move, creating a cyclical current.

• Coriolis Effect: Earth's rotation affects the path of air and water.

• Jet Stream- high speed wind pattern in the upper atmosphere.

Global Weather Patterns: Winds

• Polar cell: A circulation cell in the atmosphere that forms near the poles, characterized by sinking air and high pressure.

• Psychrometers: Instruments used to measure humidity (moisture) in the air.

• Weather front: An area where two air masses with different temperatures and pressures meet.

• Symbols for surface fronts and other significant lines: Shown on the surface analysis chart.

• ​Warm front (red): A front where warm air replaces cold air, often associated with steady precipitation.

• Cold front (blue): A front where cold air replaces warm air, often associated with severe weather.

• Stationary front (red/blue): A front where the boundary between warm and cold air masses remains nearly stationary, resulting in prolonged periods of precipitation.

• Occluded front (purple): A front where a cold front overtakes a warm front, often associated with complex weather patterns.