1. Air Masses and Ocean Currents

2. Air Masses – large volumes of air with similar temperature and humidity -move due to changing pressure conditions Wind –the movement of air between these air masses

3. Four Types of Air Masses NameCharacteristics Continental polarCool and dry Maritime polarCool and moist Continental tropicalWarm and dry Maritime tropicalWarm and moist

4. When Air Masses Meet Front – The leading edge of an air mass or where two different air masses meet -they cause sudden changes in weather such as a rise or fall in temperature and often precipitation -In the Maritimes, most precipitation is caused when cold dry air from the north meets warm, moist air from the south

5. Ocean Currents Ocean currents – the movement of water in the world’s oceans Major currents influence climate Gulf Stream – an ocean current from the south which warms the South eastern Atlantic Provinces Labrador Current – a current that carries frigid water from the North to much of the Atlantic region

6. Fog Fog – occurs commonly here - When warm gulf stream water meets cold labrador current water, the warm current cools. This causes moist air to condense into fog.