]> <OTCompoundDoc> <bodyText> <div id='content'> <h3>ESS MS Seasons - Current</h3> </div> </bodyText> </OTCompoundDoc>

Introduction

In this investigation students explore the causes of the seasons using several different techniques of inquiry.  They will create physical models, use computer models, perform experiments and measurements, and interpret data on graphs.

The investigation is organized around the perspectives of four hypothetical students who each have their own explanations for the causes of the seasons.   The views of these students are expressed in a “concept cartoon” that opens the investigation.  The concept cartoon is designed to bring out several common ideas concerning the seasons.  Your students can align themselves with one of these common ideas or express their own.  After an initial discussion of the views in the concept cartoon, students formulate an initial hypothesis.

Four activities follow that pursue the validity of each of the four ideas in the concept cartoon.  A fifth activity has students put it all together.

GSE's Addressed

This investigation focuses on GSE ESS2 (7-8) - 8b, specifically on using physical and computer models and graph data to explain the seasons.  The larger and related GSEs are expressed below to demonstrate the context for the learning.

ESS2 (7-8) -8

Students demonstrate an understanding of temporal or positional relationships between or among the Earth, sun, and moon by…

8a using or creating a model of the Earth, sun and moon system to show rotation and revolution.

8b explaining night/day, seasons, year, and tides as a result of the regular and predictable motion of

the Earth, sun, and moon.

8c using a model of the Earth, sun and moon to recreate the phases of the moon.

ESS2 (7-8) -8

Students demonstrate an understanding of gravitational relationships between or among objects of the solar system by…

8d describing the relationship between mass and the gravitational force between objects.

8e describing the  relationship between distance and the gravitational force between objects.

8f explaining that the sun’s gravitational pull holds the Earth and other planets in their orbits, just as the planet’s gravitational pull keeps their moons in orbit.


http://rites.concord.org/gallery/d/121-2/Persephone2.png

People have wondered for many years why the seasons change. Before people had the science and technology to understand the relationship between the Sun and the Earth, they created stories to explain the seasons. For example, according to an ancient Greek myth, Persephone was the beautiful daughter of Zeus and Demeter. While gathering flowers in a field one day, Persephone was kidnapped to the Underworld by Hades. Demeter, the goddess of the harvest, was heartbroken and searched everywhere for her daughter but could not find her. Finally, Hades was persuaded to allow Persephone to live for half the year with him in the Underworld and half the year with her mother. During the time that Persephone lived with Hades, Demeter was unhappy and all the plants withered and died. But when Persephone returned each year to her mother, Demeter celebrated and the plants grew again. The Ancient Greeks used this myth to explain the changing seasons.

In the following discussion, several students share their ideas about why the seasons change. As you read their ideas, think about why you think it is generally warmer in Rhode Island during the summer than in the winter. The reason for the changing seasons is the focus of this investigation.

Introduction (What causes the seasons to change?)

Section notes:
Purpose: The purpose of this pre-assessment activity is to elicit students’ ideas about seasons. A common misconception that people hold is that the reasons for the seasons is the Sun’s closer proximity to Earth in summer than in winter. It is true that at times in the Earth’s slightly elliptical orbit we are closer to the Sun. However, we are actually closer in the winter than in the summer: thus, distance is not the reason why it is warmer in the summer than in the winter. The pre-assessment probe can be used to determine whether students recognize the effect of the Earth’s tilt on its axis and the resulting intensity of sunlight as the reason for seasons.
  • Concept Cartoon
  • Clickers (Optional)

Materials (1)

Read the responses from the students above about their thoughts about the reason why we have Seasons on Earth.

When you have finished, scroll down and answer the questions below.

Click on the arrow at the bottom after you have answered the questions to move to the next page.

Which student do you agree with most?

 Kevin Josh Emma Alisha E (my own idea)

In your own words, describe your thinking about why it is warmer in the summer and cooler in winter. Provide an explanation for your answer.
Place answer here!

Engage (Why is it warmer in the summer than in the winter?)

Section notes:
In on-line (or paper) journal, students are asked:

Which student do you most agree with?

Describe your thinking about why it is warmer in the summer than in the winter. Provide an explanation for your answer.


[If available, this would be an opportunity to use clickers to the students to see how class responded]. Give students the opportunity to discuss their answers in small groups. They are to discuss which answer they chose and provide their reasoning. [If available, you can use clickers to “re-poll” to see if students changed their answers after discussing with their peers]. Most likely, there will be some differing answers. The teacher will use this opportunity to introduce the focus question for the topic:

Why do you think it is warmer on the 4th of July and colder on New Years Day in Rhode Island?

OR

Why do you think we experience seasons on Earth?


Note: Concept Cartoons (Keogh and Naylor, 1999) were created to intrigue, provoke discussion and stimulate scientific thinking among students. Often the cartoons do not have a single right answer, but they all contain a visual representation of scientific ideas in a dialog form. They offer alternative viewpoints about a situation and usually the most scientifically acceptable viewpoint is one of the alternatives. See http://www.conceptcartoons.com/index_flash.html for more information.

Using what you have learned during the discussion, write a hypothesis that we can test to explain why we experience seasons on Earth.
Place answer here!

Wrapup (1)

Kevin thinks it is warmer in the summer because the Earth is tilted on its axis.

 

In this first investigation you will explore the effect of the tilt of the Earth.

Introduction (Exploring Tilt of the Earth)

Section notes:
Teacher should remind students that the Earth rotates so that the “person” does not see darkness all the time.
Activity should be done in small groups.
  • sticky note with labels A, B, C, and D
  • styrofoam ball, with equator and 45˚N and 45˚S labels
  • string
  • flashlight
  • dowel rod with small diameter or pencil
  • pushpin
  • protractor

Materials (1)

Procedure:

1.  You will be given a Styrofoam ball with a stick through the center as a model of Earth.  The sphere should have one line to represent the equator and two other lines to represent 45˚S and 45˚N (45˚N represent the approximate latitude of Rhode Island).  Locate these lines on your model Earth.

2.  On a large table, one of 4 students should sit on each side with a sticky note in front of them labeled with points A through D.  A sticky note should be put in the center to represent the location of the sun.  Point A should be at the same location on each table (for example, on the window side of the classroom).

3. The person at point A should hold the sphere.  To start, hold it so that the axis is perpendicular to the table.

4. Pass the sphere from Position A to Position B to Position C to Position D keeping the axis perpendicular to the table. 

5.  Move the sphere back to position A.  Now tilt the dowel toward the sun (about 25˚).

6.  Keeping the axis pointed the same direction at all times, move the ball from position A to B to C to D. 

7.  Answer the questions on the next page.  As you think about the questions, you may need to repeat some of the procedure.

Explore (Exploring the tilt of the Earth)

Section notes:
The main part of this Activity examines the tilt of the Earth from the perspective of someone on Earth. An extension activity has been added to explore the tilt of the Earth from the perspective of the sun.

Page notes (Exploring the tilt of the Earth):
To make the spheres, 4" diameter spheres work well. Skewers, chopsticks, or dowel rods with a small diameter can be used for the axis.

You can estimate the position of 45˚N and 45˚S. Just find the location about halfway between the "equator" and the "pole". The lines can be hard to draw. A string works well to mark the positions. You could have your students make these if you like and have the time in class.

Many people have suggested finding a point in the classroom to use as a reference to keep the tilt constant. For instance, you could use a point on the blackboard or a location you have labeled as the North Star.

To keep the tilt constant, you could use modeling clay, a styrofoam ball cut in half, or a wood block with a 25˚ hole drilled into as a stand.

When the sphere axis is perpendicular to the table (no tilt), is there any difference in the amount of sun a person "sees" at 45˚N, as the Earth revolves around the sun at points A,B,C, and D ?  Explain your reasoning.
Place answer here!

When the sphere axis is tilted, is there any difference in the amount of sun a person at 45˚N "sees" as the Earth revolves around the sun at points A, B, C, and D?  Explain your reasoning.
Place answer here!

When the sphere is tilted at Point A, compare and/or contrast the amount of sun a person at 45˚ N and 45˚ S "sees".  Explain your reasoning.
Place answer here!

Explain (Questions about your model)

Remember, Kevin thought it was warmer in summer because the Earth is tilted on it's axis.  Does the evidence you have so far support Kevin's idea?
Place answer here!

Wrapup (Using the evidence)

In the previous activity, you modeled a planet (the Earth) revolving around the sun.  You considered this from the perspective of a person standing on Earth.  We call this Frame of Reference.  You were examining the difference from points A, B, C, and D from the Frame of Reference of a person on the Earth.

Now let us think about this from the Frame of Reference of the Sun. 

Procedure:

You should move the sphere around the sun starting at point A and then moving to points B, C, and D. 

Within your group, design your own procedure to best decide the what the Sun "sees" as the Earth revolves around it.

Write in your procedure below.  Think about whether you want to compare and/or contrast whether the tilt affects what the sun sees.  Always remember to keep the tilt in the same direction as you move from points A to B, C, and D.

 

Write in your procedure here.  List the steps as (1), (2), (3) and so on.

When the sphere axis is tilted, compare and/or contrast what the Sun "sees" at points A and B?  Explain your answer.  It may be useful to use the 45˚N, 45˚S, and equator markings as a reference.

When the sphere axis is tilted, compare and/or contrast what the Sun "sees" at points A and C?  Explain your answer.  It may be useful to use the 45˚N, 45˚S, and equator markings as a reference.

When the sphere axis is tilted, compare and/or contrast what the Sun "sees" at points B and D?  Explain your answer.  It may be useful to use the 45˚N, 45˚S, and equator markings as a reference.

Extension activity (copy of Explore Extension - Frame of Reference)

Alisha thinks its warmer in summer because the hours of daylight are longer in the summer.

 

In this activity, you will investigate how the hours of day length vary with latitude and season.

 

Discussion question:  Using your own observations, explain how the hours of day length changes in Rhode Island throughout the year.  When are days longest and when are days shortest?  Try using terms such as June Solstice (June 21), December Solstice (December 21), March Equinox (March 21), and September Equinox (September 21).

Introduction (Exploring Length of Daylight)

Computer

Materials (1)

 

Look at the graph above.  Find the line that represents 40˚N latitude.  

During which season are days longest at 40˚N?  During which season are days shortest at 40˚N?  How do the hours of daylight change throughout the year at 40˚N?
Place answer here!

Find the line that represents 80˚N.  How many hours of day length are at 80˚N in June?  How many hours of day length are at 80˚N in December?

Note:  80˚N is within the Arctic Circle.
Place answer here!

If you were to travel north from the equator to 80˚N latitude on the June Solstice, would the hours of day length increase, decrease, or stay the same?
Place answer here!

If you were to travel north from the equator to 80˚N latitude on the December Solstice, would the hours of day length increase, decrease, or stay the same?
Place answer here!

If you were to travel north from the equator to 80˚N latitude on the March Equinox or September Equinox, would the hours of day length increase, decrease, or stay the same?
Place answer here!

Using the graph, find and write down the hours of day length at 80˚N for the June Solstice, the September Equinox, the December Solstice, and the March Equinox.
Place answer here!

seasons daylight

 

 

This is a diagram looking at the Earth and Sun from a birds-eye view as the Earth revolves around the sun over the course of a year.

 

Diagram from: Pidwirny, M. (2006). "Earth-Sun Geometry". Fundamentals of Physical Geography, 2nd Edition. 7/10/09. http://www.physicalgeography.net/fundamentals/6a.html

The red line on the diagram above represents the Arctic Circle.  On the June Solstice, there are 24 hours of daylight within the Arctic Circle.  Using the diagram, explain why this is the case.
Place answer here!

On the December Solstice, there are 24 hours of darkness within Arctic Circle.  Using the diagram, explain why this is the case.
Place answer here!

On the March and September Equinoxes, there are 12 hours of day length.  Using the diagram, explain why this is the case.
Place answer here!

Explore (1)

Page notes (1):
Note that this graph is available in 3 sections in the Teacher guide Section of the Investigation.

Also note that you may want to ask students to predict the shape of the graph for 40˚S and 80˚S latitudes.

On a printed copy of the hours of day length graph, draw in a line that represents hours of day length for 42˚N latitude.  Discuss how and why the hours of day length change in Rhode Island throughout the year.

 

Remember Alisha thought that the increased hours of day light in summer compared to winter is the reason why it is warmer in summer than in winter.

 

 

 

 

Does the evidence you have so far support Alisha's idea?

Wrapup (1)

Please reflect on this activity and how it worked for your students. Record your observations, ideas, and notes for improvements here:

Josh's idea is that it is warmer in summer because the sun is more intense in the summer.

 

In this activity, you will investigate the way in which the tilt of the Earth affects the amount of solar energy an area receives throughout the year.

 

Introduction question:  Is the Earth tilted on its axis?  If so, what is the angle of tilt with respect to perpendicular (North-South)?

Introduction (Exploring variations in the intensity of sunlight)

Materials:

  • Flashlight
  • graph paper
  • pencil
  • protractor

1.  Place a piece of graph paper on the table.

2.  Hold a flashlight perpendicular to the table about 10-15 cm from the paper.

3.  Have another student trace the outline of the flashlight on the graph paper.

4.  Count the number of squares within the tracing.  If there is a partial box, count it as 1/2 of a box.

How many boxes are in the tracing?
Place answer here!

5.  Slide the graph paper so that the light from the flashlight is in a new position.  Keep the flashlight the same distance from the table (10-15 cm) as in #2 above.  Using a protractor, tilt the flashlight to an angle of 70˚ from the table.  

6.  Have another student trace the outline of the flashlight on the graph paper.

7.  Count up the number of squares within the tracing.  If there is a partial box, count it as 1/2 of a box. 

How many boxes are in the tracing at 70˚?
Place answer here!

Would you predict that the number of boxes would increase or decrease if you were to tilt the angle of the flashlight from 70˚ to 45˚ and then to 20˚?

8.  Repeat the process described above for 45˚ and 20˚.  Count up the boxes for each tracing.

How many boxes are in the tracing at 45˚?

How many boxes are in the tracing at 20˚?

How do the number of boxes relate to the intensity of the patch of light? Keep in mind the actual light in the flashlight did not change, only size of the tracing on your paper.

 More boxes means it is more intense. More boxes means it is less intense.

When is the light most intense?

 The light is most intense when the flashlight is perpendicular to the table. The light is most intense when the flashlight is at a 45˚ angle to the table. There is no difference.

When is the light least intense?

 The light is least intense when the flashlight is perpendicular to the table. The light is least intense when the flashlight is at a 45˚ angle to the table. There is no difference.

How does the angle affect the intensity of the light?  Support your answer using the number of boxes you counted above.
Place answer here!

Explore 1: Flashlight (1)

Page notes (1):
If students are using a notebook, the data from this activity could be put into a table (rows = angles, columns = # boxes).

The data from this activity can be plotted (# boxes vs angle). A prediction graph could also be made before completing the activity.

Teachers may want to note that the #boxes vs the angle is a negative relationship.

Materials:

Light source (office lamp) with 60W bulb

Clipboard

Masking tape

Ruler

Black construction paper

Temperature probe

Protractor

Extension cord

 

Procedure:

A light source will be aimed at a piece of black paper at angles of 90˚ and 45˚.  

90˚ angle:

  1. Put a piece of black paper on a clipboard.
  2. Tape a temperature probe to the paper horizontally.  Do not place tape across the end of the temperature probe and be sure that the probe is touching the paper.
  3. Set up the clipboard so that it is sideways and perpendicular to the table.  It should be at a 90˚ angle to the light.
  4. Place the light source approximately 30 cm from the clipboard so that it is lined up directly with the temperature probe.
  5. Start the reading on the temperature versus time graph and then after a few seconds turn on the light source.
  6. Allow the system to run for 10 minutes (600 s).
  7. Stop the reading on the temperature versus time graph.
  8. Write down the initial temperature, the final temperature, the total time, and make a sketch of the temperature versus time graph in your notebook.
  9. Subtract the final temperature from the initial temperature to get the change in temperature.

probe picture 90 degrees

45˚ angle:

  1. Put a piece of black paper on a clipboard.
  2. Tape a temperature probe to the paper horizontally.  Do not place tape across the end of the temperature probe and be sure that the probe is touching the paper.
  3. Set up the clipboard so that it is sideways at a 45˚ angle to the light. Make sure your light source is perpendicular to the table (not facing down toward the probe). 
  4. The temperature probe should be approximately 30 cm from the light source.  Since the clipboard is now at an angle, the bottom of the clipboard will be less than 30 cm away while the top of the clipboard will be more than 30 cm away from the light source.
  5. Start the reading on the temperature versus time graph and then after a few seconds turn on the light source.
  6. Allow the system to run for 10 minutes (600 s).
  7. Stop the reading on the temperature versus time graph.
  8. Write down the initial temperature, the final temperature, the total time, and make a sketch of the temperature versus time graph in your notebook.
  9. Subtract the final temperature from the initial temperature to get the change in temperature.

probe picture 45 degrees

What is the change in temperature when the paper is at a 90˚ angle relative to the light?  If your class this in groups, you may want to use the class mean value.
Place answer here!

What is the change in temperature when the paper is at a 45˚ angle relative to the light?  If your class did this in groups, you may want to use the class mean value.
Place answer here!

Was the change in temperature greater when the paper was at an angle of 90˚ or at an angle of 45˚?
Place answer here!

In which case is the light most intense, and in which case is the light least intense?
Place answer here!

How is the intensity of the light related to the change in temperature?  Support your answer with the data you collected.  
Place answer here!

Explore 2: Temperature Probes (1)

Page notes (1):
You may want to give your students a few minutes to play with the temperature probes before beginning the activity. Ask them to figure out which end of the probe is most sensitive. In addition have them auto-scale the graph and figure out how to read temperatures off the graph.

This activity could be done as a demonstration or as a "station" set up within the classroom if only one computer is available. The probe will need to cool between the 90˚ and 45˚ experiments. This may take up to 5 minutes.

You may want to have the students figure out how to calculate the change in temperature instead of including it as part of the procedure.

Explore 2: Temperature Probes (Concentrated vs. Spread Out LightExperiment)

Explore 2: Temperature Probes (3)

In this activity you will investigate an online computer model of the Earth and Sun and then answer some questions about the model.

First, play with the model, letting it run, and starting and stopping it at different times. The model has several parts. See if you can understand what each part shows.

Click here for the model of the Earth and Sun.

Note:

1) If the model does not run using the FireFox browser, then copy and paste the URL below into Internet Explorer.

2) If you are reading a printed version of the investigation, type the URL below into a browser to view the model.

Model URL: http://www.astro.illinois.edu/projects/data/Seasons/seasons.html

If you need assistance, please ask your teacher.

Model of Earth and Sun

After you have had some time examining the whole model, pay particular attention to the grid on the lower right side. Stop the model when the dates below flash up, and examine how the yellow spot on the grid changes throughout the year.

  • June 22
  • September 23
  • December 22
  • March 23

What do you think the grid in the lower right of the Earth and Sun model is showing?

Explore 3: Computer model (The Earth and Sun Computer Model)

Estimate the number of squares that are filled by the beam of sunlight at position #1?

content goes here ...

Estimate the number of squares that are filled by the beam of sunlight at position #2?

Estimate the number of squares that are filled by the beam of sunlight at position #3?

Estimate the number of squares that are filled by the beam of sunlight at position #4?

At position #1 the sunlight in the northern hemisphere is:

 More intense Less intense In between

At position #2 the sunlight in the northern hemisphere is:

 More intense Less intense In between

At position #3 the sunlight in the northern hemisphere is:

 More intense Less intense In between

At position #4 the sunlight in the northern hemisphere is:

 More intense Less intense In between

The season depicted at position #1 on the diagram is:

 Spring Summer Autumn Winter

The season depicted at position #2 is

 Spring Summer Autumn Winter

The season depicted at position #3 is

 Spring Summer Autumn Winter

The season depicted in position #4:

 Spring Summer Autumn Wnter

Using the number of boxes to support your answer, how did you decide whether the sunlight was more intense, less intense, or in between?

This diagram will help you answer the questions that follow. Using the computer model of the earth and sun, answer all questions from the perspective of an observer in the northern hemisphere.

Explore 3: Computer model (Questions for the Earth and Sun Computer Model)

Run the model of the Earth and Sun again and notice how the distance between the Earth and Sun varies throughout the year.  When is the earth closest to the sun, and when is it furthest away?  Is this what you expect?

Using what you have learned, describe the intensity of the sun in Rhode Island in each of the four seasons.  Consider when the sun is more intense or less intense.

Explore 3: Computer model (Computer Model Wrap Up Questions)

Examine the three diagrams below.  Then scroll down to answer the questions.  You may scroll back to look at the diagrams when necessary.

When is the sun directly overhead at the equator?

 June (Summer) Solstice Spring Equinox and Autumnal Equinox December (Winter) Solstice

When is the sun directly overhead at 23.5˚N latitude?

 June (Summer) Solstice Spring Equinox and Autumnal Equinox December (Winter) Solstice

When is the sun directly overhead at 23.5˚S latitude?

 June (Summer) Solstice Spring Equinox and Autumnal Equinox December (Winter) Solstice

What is located on Earth at 23.5˚N latitude? Use the diagram or a globe to help answer the question.

 Equator Tropic of Cancer Tropic of Capricorn

What is located on Earth at 23.5˚S latitude? Use the diagram of a globe to help answer the question.

 Equator Tropic of Cancer Tropic of Capricorn

Using your answers above, explain why the area between 23.5˚N and 23.5˚S is called the Tropics?
Place answer here!

How do the latitudes of the Tropic of Cancer and the Tropic of Capricorn compare to the angle of the tilt of the Earth on it's axis?
Place answer here!

Using the diagrams, how many times a year is the sun directly overhead at the equator?  
Place answer here!

Compare and/or contrast the solar intensity within the Tropics to areas outside the Tropics.  To help answer your question, consider the following questions.  Is the sunlight most intense when the sun is directly overhead or at an angle in the sky?  Why is the sun never directly overhead outside of the Tropics?
Place answer here!
Look at the diagram of the June Solstice.  How does the solar intensity at 23˚N compare to the solar intensity at 23˚S?  Using what you have learned, explain why there is a difference in solar intensity at the two locations?

 
Look at the diagram of the December Solstice.  How does the solar intensity at 23˚N compare to the solar intensity at 23˚S?  Using what you have learned, explain why there is a difference in solar intensity at the two locations?

 

Explore 4: When is sun overhead? (1)

Josh's idea was that the sun was more intense in the summer and less intense during the winter, which is why the summer air temperature is warmer than the winter air temperature.

Does the evidence you have so far support Josh's idea?
Place answer here!

After exploring some ideas, do you want to change your hypothesis about the reason why we have seasons?  If so, write a new hypothesis to explain the seasons we observe on Earth.
Place answer here!

Wrapup (1)

Emma thinks that it is warmer in summer because the Earth is closer to the sun in the summer. In this activity you will investigate whether the distance between the sun and the Earth explains why we experience seasons on Earth.

Introduction (Exploring distance between the Earth and Sun)

Computer:

Citation: Pidwirny, M. (2006). "Earth-Sun Geometry". Fundamentals of Physical Geography, 2nd Edition. 7/10/09. http://www.physicalgeography.net/fundamentals/6h.html

Materials (1)

Procedure:

Examine the diagram and answer the questions below.

 

sun earth distance

Diagram citation: Pidwirny, M. (2006). "Earth-Sun Geometry". Fundamentals of Physical Geography, 2nd Edition. July 10, 2009. http://www.physicalgeography.net/fundamentals/6h.html

 

What date and during what season in the northern hemisphere is the Earth closest to the sun?
Place answer here!

What date and during what season in the northern hemisphere is the Earth farthest from the sun?
Place answer here!

Is the difference in distance between the Sun and the Earth during the year an explanation for the seasons we observe in the Northern Hemisphere?  Support your answer using your answers above and the diagram.
Place answer here!

Explore (1)

Page notes (1):
Students could be asked to calculate the % difference in distance at the perihelion and aphelion to show that this difference in the distance is small.

Remember that Emma thinks it is warmer in summer because the Earth is closer to the sun in the summer.

Does the evidence you have so far support Emma's idea?
Place answer here!

Wrap-Up (1)

In this investigation, you have explored several students' ideas about why we experience seasons on Earth. In this activity, you will synthesize all of this information in order to test your hypothesis.

Introduction (1)

Computer

Materials (1)

 

Insolation is a measure of the solar radiation that shines on the Earth's surface over a given surface area in a given time.  It takes into account the angle of incoming radiation and the length of daylight.  NASA defines insolation as "the rate at which direct solar radiation is incident upon a unit horizontal surface at any point on or above the surface of Earth".

Look at the line that represents 0˚.  What do we call 0˚ latitude?
Place answer here!

During which months is the solar intensity highest at the equator?
Place answer here!

What is the approximate maximum solar intensity at the equator?
Place answer here!

During which months is the solar intensity lowest at the equator?
Place answer here!

What is the approximate minimum solar intensity at the equator?
Place answer here!

Is there a large difference in solar intensity from season to season at the equator?
Place answer here!

Look at the line that represents 90˚N.  What do we call 90˚N latitude?
Place answer here!

During which months is the solar intensity highest at the North Pole?
Place answer here!

What is the approximate maximum solar intensity at the North Pole?
Place answer here!

During which months is the solar intensity lowest at the North Pole?
Place answer here!

What is the minimum solar intensity at the North Pole?
Place answer here!

The average yearly solar intensity at the equator is 7, and the average yearly solar intensity at the North Pole is 3.  Why is the yearly average solar intensity greater at the equator even though the maximum point in solar intensity is at the North Pole?    

 
Place answer here!

Why is the solar intensity zero during the winter months?
Place answer here!

Why is the solar intensity greater at the North Pole than at the equator in June?
Place answer here!

Do you think someone living at the equator would notice large changes in temperature between January and July?
Place answer here!

Do you think someone at the North Pole would notice large changes in temperature between January and July?
Place answer here!

Use what you have learned about the tilt of the Earth and intensity of sunlight to answer the following question.  Explain the difference in solar intensity throughout the seasons at the equator, North Pole, and 42˚N (Rhode Island).
Place answer here!

Convince a person that distance does not explain the difference between seasons.
Place answer here!

Explore: Solar intensity (Engage 1)

Please reflect on this activity and how it worked for your students. Record your observations, ideas, and notes for improvements here:

1. If the tilt of the Earth on its axis was 10˚ instead of 23.5˚, the equivalent of the Tropic of Cancer would be found at what latitude?

 23.5˚N 23.5˚S 10˚N 10˚S

2. The longest day of the year in the Southern Hemisphere is approximately ___.

 December 21 June 21 September 21 March 21

3. What is the relationship between the angle of incoming sunlight and the intensity of the light?

 the light is most intense when the angle is smallest the light is most intense when the angle is 90˚ the light is least intense when the angle is 90˚ there is no relationship

4. The solar insolation at the equator is ___.

 the same all year highest on the Summer Solstice and the Winter Solstice highest on the Spring Equinox and Fall Equinox constantly changing because the tilt of the Earth on its axis changes throughout the year

Look at the diagram below to answer the question.

5. In the diagram, point A represents ___.

 Northern Hemisphere Spring Northern Hemisphere Summer Southern Hemisphere Spring Southern Hemisphere Summer

This diagram should be used with question #5.

6.  You are going on a trip to Sydney, Australia (34˚S latitude) from January 3-10.  What kind of clothing should you pack for this trip?  Explain your reasoning.

7.  Suppose there is a planet exactly the same at Earth, called Searth, but the tilt of Searth on its axis is 0˚ instead of 23.5˚.  Write an essay that compares and/or contrasts the seasons observed on Searth and Earth.  Please use words from the word bank provided: solar intensity, latitude, equator, pole, Northern Hemisphere, Southern Hemisphere, angle of incoming light, length of daylight.

8.  Pick one the student ideas from the Concept Cartoon below and develop a logical argument using evidence from the activities you did to prove or disprove the idea.

 

This cartoon should be used with question #8.

 

 

 

Assessment-middle school (Middle School Assessment)

Page notes (Middle School Assessment):
The following questions represent some sample assessment questions adapted from suggestions during the summer short courses.

Assessment activity suggestions were:
picture book design (www.tikatoc.com)
video
song
Powerpoint presentation
Performance

Use this link to download a PDF of this assessment.

1.  If the tilt of the Earth were increased by 10˚, how would the Seasons we observe be different that what we observe now?  Support your answer using the following concepts: solar intensity, angle of incoming light, length of daylight, latitude, equator, polar region, tropics.

2.  From the perspective of a person standing on Earth, describe the changing location of the sun over the course of one year.  Include the locations where one would find the sun directly overhead at local noon.  Compare this to the position of the Earth and the Sun over the course of one year from the perspective of an alien with a birds-eye view of the Earth and Sun.  Include terms such as latitude, tilt toward, and tilt away.

Assessment-High School Essays (1)

Use this link to download a PDF of this assessment.

Concept Cartoon Pre-Assessment

  • Persephone Photo: http://search.creativecommons.org/  Image: http://tbn3.google.com/images?q=tbn:P9zzjY3ssebxWM:http://www.geocities.com/Athens/Aegean/7490/persephone1.jpg
  • High School Classroom Photo:  http://search.creativecommons.org/  Author:David Shankbone

Length of daylight (Alisha's idea)

Intensity of Sunlight (Josh's idea)

  • Temperature probe experiment based on: http://www.pasco.com/earth/atmosphere/understanding-seasons.cfm
  • Data and Animations for Teaching Astronomy (DATA) from University of Illinois Department of Astronomy, http://www.astro.illinois.edu/projects/data/AboutData.html

Sun-Earth Distance (Emma's idea)

Solar Intensity Graph (Wrap Up)

  • Data from NASA Atmospheric Science Data Center

References (1)