Topic 6 Seasons in 3D Report

Name: ______________________________________ Date: ________________________ Student Exploration: Seasons in 3D Vocabulary: axis, equinox, latitude, Northern Hemisphere, revolve, rotate, solar energy, solar intensity, Southern Hemisphere, summer solstice, winter solstice Prior Knowledge Question (Do these BEFORE using the Gizmo.) Both New Zealand and Argentina are in the Southern Hemisphere (south of the equator). What time of year would you plan a ski vacation in New Zealand ? _____________________ What time of year would you visit the beaches of Argentina? _________________________ Gizmo Warm-up Describe Earth’s movements: _________________________________________________ _________________________________________________________________________ Click Reset ( ) , and then click Play again. Look at the side view of Earth at the bottom of the SIMULATION pane. What do you notice about Earth’s axis as Earth revolves around the Sun? ________ When is the N orth ern H emisphere tilted toward the Sun? ___ ______ __ ___ ________ When is the Southern Hemisphere tilted toward the Sun? ____ _________________ Get the Gizmo ready: Activity A: Click Reset Height of the Sun . Question: How do seasons compare in the Northern and Southern Hemispheres? Compare : Is the Northern Hemisphere tilted toward or away from the Sun? ________________ How much light is fallin g on the Northern Hemisphere compared to the Southern Hemisphere? ________________________________________________________ Change the date to December 21. On this date, which hemisphere is receiving more sunlight? ___________________________________________________________ Observe : Complete Analyze : On which date was the noon Sun higher in the sky? ________________________ Explain : How does the orientation of Earth’s axis relate to the position of the Sun in the sky? Predict : On the DESCRIPTION pane, set the Latitude to -45° (45° S). For this latitude, on which date do you expect the noon Sun to be highest? Circle your choice. Observe : Complete Analyze : On which date was the noon Sun higher in the sky? ________________________ Explain : Why were your results for the Southern Hemisphere opposite of what you found for the Northern Hemisphere? Infer : Based on the height of the Sun in the sky, at what time of year is it summer in the Southern Hemisphere? When is it winter in the Southern Hemisphere? Explain. Get the Gizmo ready: Click Activity B: Reset and make sure the Solar intensity Simulation s peed slider is all the way to the left. Question: Why is it warmer in summer than in winter? Describe : Look up the latitude of your city or town. Set the Latitude to this value. What town do you live in, and what is its latitude? ___________________________ What is the temperature of a typical summer day in your town? _________________ What is the temperature of a typical winter day in your town? ___________________ Observe : Complete At what time of day is solar intensity greatest? ______________________________ What is the solar intensity at night? _______________________________________ Why do you think the solar intensity follows this pattern? ______________________ Gather data : Record the solar intensity at noon on March 21. Then record the times of sunrise (solar intensity begins to rise) and sunset (solar intensity returns to zero). Based on these times, calculate the hours of daylight. Repeat for each solstice and equinox . Date Noon solar intensity (W/m2h) Sunrise Sunset Hours of Daylight March 21 June 21 September 23 December 21 Analyze : Use the table to compare the hours of daylight on the equinoxes (March 21 and September 23) and solstices (June 21 and December 21). What is the longest day of the year? _______________ Shortest? ______________ What do you think the word equinox means? _______________________________ (Activity B continued on next page) Activity B (continued from previous page) Explain : Why is the noo n solar intensity greater on the summer solstice than on the winter solstice ? __________________________________________________________________ Observe : Click Reset and set the Simulation speed to its highest value. On the GRAPH tab, s elect the Year graph . Cl ick Play . After a year has passed, sketch the resulting graphs at right . Summarize : Seasonal changes are related to the length of a day and the height of the Sun in the sky. Describe how these two factors change throughout a year, and how this relates to the seasonal changes you observe in your home town. On your own : Change the Latitude to the opposite of its current value, and create a year graph for this latitude. Sketch this graph on a separate sheet of paper, describe the patterns that you see in this graph, and explain why the graph looks the way it does. Turn in this graph with this sheet.