1. Weather and Climate

2.  Weather- the condition of the bottom layer of the earth’s atmosphere in one place over a short period of time - descriptions of weather include: temperature, moisture/precipitation, wind - example: cold, snowy, windy - almost in constant state of change - may influence other areas/regions

3.  Climate- weather patterns that an area typically experiences over a long period of time - factors of climate: elevation, latitude, location to landforms/water

4.  The Sun - the ultimate source of the earth’s climate and of life on earth

5.  The Greenhouse Effect - solar radiation - small amount reaches earth’s atmosphere - some reflected back to space - some remains to warm earth’s land and water *atmosphere prevents heat from escaping back into space too quickly

6.  Rotation - rotation- the spinning motion of the earth as it travels through space - axis- invisible line through the center of the earth from pole to pole (23 ½ tilt) - one rotation completed in 24hrs. - Earth spins from west to east

7.  Revolution - orbit- the earth moves around the sun in a nearly circular path - revolution- one complete orbit around the sun - one revolution completed every 365 ¼ days- length of a year - Tropic of Cancer (23 ½ N) and the Tropic of Capricorn (23 ½ S) receive the most direct sunlight

8.  Solstices - June 21 and December 21 - the days when the sun appears directly overhead at the Tropics of Capricorn and Cancer  Equinoxes - March 21 and September 23 - the lengths of day and night are nearly equal everywhere on the earth

9.  Latitude and Climate - The sun’s rays always fall most directly at or near the Equator - the rays grow less direct as they fall closer to the poles  Tropical Zones  Temperate Zones  Polar Zones

10.  Nearby Bodies of Water - large bodies of water affect the surrounding climates - winds that blow over water take on the water’s temperature - milder climates  Elevation  Nearby Landforms

11.  Climate Regions - tropical - dry - moderate - continental - polar/highlands

12.  Global warming