Air masses get their characteristics based on where they form

The abbreviations used to classify air masses use the following letters: c, m, T, P, and A. For each letter, describe its property: Word Means c m T P A continental dry maritime moist Tropical warm Polar cold Arctic very cold

What would their characteristics be? mT cP warm and moist cold and dry

What type of air mass would form over each area? Please label. cA mP mP cP cT mT mT mT

World Air Mass Source Regions

Animation #1 http://www.classzone.com/books/earth_science/terc/content/visualizations/es2001/es2001page01.cfm?chapter_no=20

cP air mass dry, cool air High Pressure Area mT air mass warm, moist air Low Pressure Center

cP air mass dry, cool air High Pressure Area mT air mass warm, moist air Low Pressure Center

cP air mass dry, cool air High Pressure Area mT air mass warm, moist air Low Pressure Center

cP air mass dry, cool air High Pressure Area mT air mass warm, moist air Low Pressure Center

cP air mass dry, cool air High Pressure Area mT air mass warm, moist air Low Pressure Center

Air Masses Facts: Air mass is a region of air with similar properties in the atmosphere Air mass typically move from the west to the east in the Northern Hemisphere under the influence of the prevailing westerlies. Example: Hot, dry air from the continental tropical air mass will bring hot, dry weather to Texas when it moves in from Arizona. Masses of air that stay in place for some length of time take on the characteristics of temperature and humidity from the surface of the earth over which the air stands. Masses of air that originate over the ocean tend to be moist There are four major types of air masses that affect the weather in the United States: Maritime Tropical Maritime Polar Continental Tropical Continental Polar

Characteristics Name Characteristics Maritime Tropical Forms near the equator. Warm, moist air Summer- very hot, humid weather Winter - rain or snow Maritime Polar Forms over the Pacific Ocean in both the winter and the summer. Summer – cooler temperatures to the eastern states and fog to California and other western states. Winter- Heavy snow and very cold temperatures Continental Tropical Forms over land in Mexico. Brings dry, hot air to the southwestern states. Continental Polar Forms over land in northern Canada. Winter- very cold temperatures in the United States

High and Low Pressure Systems High Pressure Areas (H) – air tends to sink, winds blow outward from the center, turning clockwise. High pressure area usually brings clear skies, dry weather, and gentle winds. Low Pressure Areas (L) – the air tends to rise, and winds spiral in toward the center in a counterclockwise direction. The low pressure areas usually brings cloudy, wet weather, often with strong, gusty winds.

High and Low Pressure Systems Areas of high pressure can be caused when cool air is sinking and pressing on the ground. When warm air rises, however, it causes a region of low pressure. Regions of sinking air are called highs, high pressure regions, or anticyclones. Clear skies and fair, dry weather usually occur in these regions. Regions of rising air are called lows, low pressure regions, depressions, or cyclones. Clouds, rain, and strong winds often occur in these regions.