1. Warm-up Rank the following from largest to smallest effect on the strength of the seasons: Rank the following from largest to smallest effect on the strength of the seasons: Tilt, distance, latitude Tilt, distance, latitude

2. Notes: Solar Angle Latitude and Seasons Essential Question: How does insolation angle affect climate?

3. Latitude …is angle or distance away from the equator. Equator = 0° North, South poles = 90° Everett = 48 ° 90° 0° 90°

4. Latitude Energy concentrates on a small area  more energy / area = warmer Energy spreads out over a large area Less solar energy per area = colder 100 % energy 40 % energy High latitudes: Low latitudes:

5. Seasons: Angle of the Sun More energy in summer warmer Less energy in winter in wintercolder 1 km 2

6. Tilt of the Earth 23.5 ° Tilt is the cause of Earth’s seasons Causes the sun’s highest angle in the sky to change with the seasons Distance to the sun effects are much, much smaller!

7. Seasons (tilt, solar angle) More direct, concentrated sunlight … and more hours per day  warmer Less solar heat per area = colder Fewer hours of solar energy each day Summer Winter: Summer:

8. Make a chain… Tilt or latitude With your group, come up with a chain that explains a season or latitude difference using the sequence shown in the flow chart at left. With your group, come up with a chain that explains a season or latitude difference using the sequence shown in the flow chart at left. Include a sketch. Include a sketch. Sunlight change More/less energy Specific climate difference

9. Falkland Islands (52° S), June vs. Dec. Tilt or latitude Sunlight change More/less energy Specific climate difference DecJune Tilt Low solar angle means less concentrated light in June Less energy Colder/winter in June Moreenergy Less Lessenergy

10. Make a chain… include a sketch. Tilt or latitude Sunlight Change More/less energy Specific climate difference Group tasks: 1.Everett vs. Hawaii 2.L.A. vs. Anchorage 3.Quito (on equator) 4.Spokane: Dec vs. June 5.48° N vs 20° S 6.30° N vs. 30° S 7.Sydney: Dec vs. June 8.80° S: Dec vs June

11. Equator: Low latitude  high sun angle  more solar energy per area  hot weak seasons (sun always gets high overhead + little change in daylight hours) Near Poles: High latitude  low sun angle  less solar energy per area  cold Stronger seasons (large changes in solar angle and number of daylight hours.)