1. What Causes Climate and seasons? Chapter 17 Section 1

2. Objectives  What is the difference between climate and weather?  What are the factors that influence temperature and precipitation?  What causes the seasons?

3. Weather vs. climate  Weather is the day to day conditions of the atmosphere: temperature and precipation, etc.  Climate is the average weather condition in an area over a long period of time.

4. Main factors of climate  The main factors that influence temperature are:  Latitude: Where are you on the globe?  Altitude: higher elevations are exposed to more wind, water, and ice

5. Latitude and altitude l

6.  Distance from large bodies of water: water heats and cools slower than land, so it keeps nearby land from having temperature extremes –Ex. Savannah does not get as hot or as cool as Atlanta  Ocean currents: warm ocean currents warm the nearby land and cool currents cool it

7. What causes seasons?  The seasons are caused by the tilt of the Earth’s axis as Earth orbits the sun –When the Northern Hemisphere is tilted towards the sun, it is summer –When the Northern Hemisphere is tilted away from the sun, it is winter. –When it is not tilted toward or away, it is spring or fall.

8. Seasons

9. Summer/Winter  Summer Solstice: June 21: Longest day of the year –Northern Hemisphere tilted toward the sun  Winter solstice: Dec. 21: shortest day of the year –Northern hemisphere tilted away from the sun

11. Equinoxes  Vernal equinox: March 20: First day of spring: Earth tilted neither away from or towards the sun  Autumnal Equinox: September 20: First day of fall: Earth tilted neither away from or towards the sun

12. Example  http://highered.mcgraw- hill.com/sites/007299181x/student_view0/ch apter2/seasons_interactive.html

13. Think-Pair-Share  Think for a moment: –How might Earth’s climates be different if Earth were not tilted on its axis. –Describe the seasonal changes of areas located at or on the equator. How do you think their climate is affected by the Earth’s tilt?  Pair with your neighbor and discuss your thoughts about this concept.  Share with your table the thoughts you and your partner came up with. Were they the same or different than the other pairs at your table?