1. Weather and Climate Why doesn’t it ever snow in El Cajon?

2. Weather and Climate  Weather  Atmosphere :  The condition of the bottom layer of the earth’s atmosphere in one place over a short period of time.  A multilayered band of gases, water vapor, and dust above the earth. – Involves temperature, moisture or precipitation, and wind. – Is always in a constant state of change.

3. Weather and Climate  Climate:  The term for the weather patterns that an area typically experiences over a long period of time. – Dependent on: 1. Elevation 2. Latitude 3. Location in relation to nearby landforms and bodies of water.

5. Weather and Climate  The Sun  The ultimate source of the Earth’s climates is the sun.  93 million miles away.  Gives off energy and light.

6.  The Greenhouse Effect Effect – The sun gives off radiation, and some of it is reflected back into space by the atmosphere, but enough remains to warm the Earth’s land and water. –The Earth’s atmosphere serves like a green house.  The atmosphere also prevents heat from escaping back into space.  Without the greenhouse effect, the Earth would be too cold for most living things.  Not all places on the earth get the same amount of heat and light from the sun; it is dependent on the relative position of the sun and the Earth. / / Weather and Climate http://www.funnyordie.com/videos/48c27b503a/none-like-it-hot-from-poundsmack

7. Weather and Climate  Rotation  Orbit  Revolution – The Earth is constantly spinning on it’s axis through space Earth’s axis  23 degrees  The Earth completes one rotation every 24 hours.  Spins from west to east, so the sun appears to rise in the east and set in the west. – The path the Earth takes as it revolves around the Sun – One complete orbit around the sun = 365 1/4 days = 1 year  http://www.classzone.com/books/earth_science/terc/content/visualizations/es0404/es0404page01.cfm?chapter_no=visualiz ation http://www.classzone.com/books/earth_science/terc/content/visualizations/es0404/es0404page01.cfm?chapter_no=visualiz ation http://www.classzone.com/books/earth_science/terc/content/visualizations/es0404/es0404page01.cfm?chapter_no=visualiz ation

8. Rotation and Revolution Cont.  Is the Earth Straight up and down?  How does it look? (Draw a picture in your notes)  What are the names of the two places that the Earth receives the most direct sunlight?  What happens when the North Pole is pointed at the Sun? Which Hemisphere is enjoying the Summer weather? –If the South Pole is pointed at the sun, the reverse.  What are the Summer and Winter Solstices? At what date do they occur?  What are the Spring and Fall Equinoxes? At what date do they occur?  The lengths of day and night are nearly equal everywhere on earth. No it sits at a 23 degree tilt Tropic of Cancer and the Tropic of Capricorn The Northern Hemisphere has longer and warmer days. The Northern Hemisphere When the Sun appears directly over both cancers. June 21 and December 21 The Sun, at noon are directly over the equator. March 21 and September 23.

9. Weather and Climate Latitude: Lines of Latitude are used to divide the world into zones.  Tropical Zones = – Hot year-round  Temperate Zones = – Cooler than the tropics and have a wide range of temperatures.  Polar Zones = – Always cool, and bitterly cold.  Low-latitude zones reaching 23 degrees N & S of the Equator  Middle Latitudes that extend from 23 degrees N to 66 degrees N and from 23 degrees S to 66 degrees S  High Latitudes from 66 degrees N and S to the poles. http://www.classzone.com/books/earth_science/terc/content/visualizations/es2103/es2103page01.cfm?chapter_no=21

11. Climate Zones

12.  Sun’s Heat  Convection:  Air =  Water =  Heat is distributed by a process called convection.  The transfer of heat from one place to another. – Convection takes place in both air and water.  Winds – Warm air and water move from the equator toward the poles.  Currents – Cool air and water move from the poles toward the equator. Weather and Climate

15. Wind –Winds move from areas of high pressure to areas of low pressure. –Wind redistributes the sun’s heat over the earth’s surface. –If the world were still, the winds would blow straight. –Since the earth is rotating, the movement of winds deflects, or bends = Coriolis Effect. –In the Northern Hemisphere, winds curve to the right. –In the Southern Hemisphere, winds curve to the left. http://www.ambientweather.com/cuunstwimap.html

16. Precipitation- Any form of water that falls to the earth  Convectional -when warm air rises and cools –-ex: Thunderstorms and tornadoes

17. Orographic  when warm air is forced upwards because of a mountain

18. Frontal  When pockets of cold air go under warm air- –Type Found in San Diego