1. Where it all starts.

2.  Mars – too thin, so it doesn´t absorb enough heat  Venus – so dense, the heat doesn´t escape!  Earth – the perfect combination!!!  Some of the sun´s energy is absorbed by the atmostphere  Some is absorbed by the planet´s land and water  Some is reflected back into space  If we keep polluting our atmosphere could become thick and dense like Venus´s atmosphere!!!

3.  Radiation  Electromagnetic waves (the sun´s heat arrives)  Conduction  Direct contact (air touching warm land)  Convection  Movement in gases & liquids  Heat always rises because it is lighter/less dense  What does this motion create?  The motion of wind and ocean currents!!!!

4.  Temperature differences are caused by the Earth´s curved surface  The equator gets a lot more heat than the North and South poles (obvio)  The motion is also affected by the Earth´s rotation

5.  Trade winds - Near the equator all the wind blows west and toward the equator.  Prevailing westerlies  On either side of the trade winds, the prevailing westerlies blow opposite.  Always blow to the east (from the west)  Always blow away from the equator  Polar easterlies - Polar winds always blowing west (from the east) and towards the equator (away from the pole)  See page 352 in text book

6.  Jet streams follow the prevailing westerlies at their north and south border  Jet streams average between 97-185 km/hr  Just like sailors have used surface winds to sail their boats, pilots use jet streams  If they are going east, they save gasoline by going in the jet stream.  If they are going west they avoid the jet streams.

7.  Land heats and cools faster than water!!!!  During the day air above the land is heated by conduction  The heated air…  Rises!!!!  So at the beach in the day, there is a current from the cool sea air going up.  At night the air above land is cooler  So at the beach at night, there is a current going down towards the water.

8.  During the winter, the land is much colder than the ocean, so like the beach at night, the air moves away from the land.  During the summer, the land is much warmer so the wind blows in from the sea. This wind is usually full of moisture and brings a lot of rain.