EMS- 5.2 Reasons for the Seasons

EMS- 5.2 Reasons for the Seasons

By: Ms. Bailey*

​Lesson Objective​

​KWBAT create a model for different seasons in the northern and  southern hemispheres.

KWBAT predict the season given the relative position of the Earth to the sun and Earth on its axis.

​TEKs: 8.7(A): Model and illustrate how the tilted Earth rotates on its axis, causing day and night, and revolves around the Sun causing changes in seasons.

​Scholars will learn:

​The revolution of the Earth around the Sun causes changes in seasons. 

• The northern and southern hemispheres experience opposite seasons at the same time due to Earth’s tilt (tilted 23 degrees).

• Winter occurs when the hemisphere is tilted away from the sun. Therefore, the hemisphere has less intense sunlight, colder temperatures and shorter days.

• Summer occurs when the hemisphere is tilted towards the sun.  Therefore the hemisphere has more intense sunlight, warmer temperatures and longer days.

​Lesson Vocabulary

​Season: one of four periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

Northern hemisphere: the top half of Earth from the equator up

Southern hemisphere: the bottom half of Earth from the equator down.

Multiple Choice

Season...

• one of four periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

• one of three periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

• one of two periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

Multiple Choice

Northern Hemisphere...

• the top half of Earth from the equator up

• the bottom half of Earth from the equator up

• the left half of Earth from the equator up

• the right half of Earth from the equator up

Multiple Choice

Southern Hemisphere...

• the bottom half of Earth from the equator down.

• the top half of Earth from the equator down.

• the left half of Earth from the equator down.

• the right half of Earth from the equator down.

​Welcome back, Astronomers!  Yesterday you explored how the sun’s rays hit different parts of Earth at different angles due to Earth’s curvature and angle. Today, you will be using this information to create a model to predict the four seasons based on Earth’s relative position to the sun and Earth on its axis.

Open Ended

Why does the sun’s intensity differ in angle and location on Earth?

SS: The sun's intensity differs because....

​Questions......

​1. What is rotation? Give me an example.

2. What is revolution? Give me an example.

3. How long does it take the Earth to make one complete rotation?

4. How long does it take the Earth to make one complete revolution? ​

Multiple Choice

Which diagram, Diagram 1 or Diagram 2, represents revolution?

• Diagram One

• Diagram Two

Multiple Choice

Which diagram, Diagram 1 or 2, represents rotation?

• Diagram One

• Diagram Two

Multiple Choice

How long does it take Earth to rotate? How long does it take Earth to revolve?

• The Earth rotates every twenty-four hours. The Earth makes one complete revolution every three hundred sixty-five days.

• The Earth rotates every three hundred sixty-five days. The Earth makes one complete revolution every twenty four hours

• The Earth rotates every forty-eight hours. The Earth makes one complete revolution every three hundred sixty-five days.

​Key Concept

​There are seasons on Earth because Earth is tilted, so one half of Earth is always getting more sunlight than the other. Since Earth moves around the sun, which hemisphere gets more sunlight switches—sometimes it’s the northern hemisphere and sometimes it’s the southern hemisphere.

​Key Concept

​Winter occurs when the hemisphere is tilted away from the sun. Therefore, the hemisphere has less intense sunlight, colder temperatures and shorter days.

​Key Concept

​Summer occurs when the hemisphere is tilted towards the sun. Therefore, the hemisphere has more intense sunlight, warmer temperatures and longer days.

​We know that the sun’s rays don’t hit Earth equally.  The unequal intensity of the sun’s rays is part of the reason we have seasons on Earth.  Recall that Earth is divided into two hemispheres: the northern hemisphere and the southern hemisphere.  We are in the northern hemisphere and currently experiencing winter/spring.  Interestingly, countries in the southern hemisphere such as Brazil or Australia, are experiencing the opposite season: summer/fall.

Open Ended

Make a prediction! What causes seasons on Earth?  Why do the Northern and Southern hemispheres experience opposite seasons at the same time?

SS: The Northern and Southern hemisphere experience opposite seasons because....

Multiple Choice

Left box is which season in the Northern hemishere?

• summer

• winter

• spring

• fall

Multiple Choice

Bottom box represents which season in Norhtern hemisphere?

• summer

• winter

• spring

• fall

Multiple Choice

Right box, shw which season in he Northern hemisphere?

• summer

• winter

• spring

• fall

Multiple Choice

top box represents which season in the Northern hemisphere?

• summer

• winter

• spring

• fall

Open Ended

What causes seasons on Earth? Why do the northern and southern hemispheres experience opposite seasons?

​Let's Apply Our Learning!

Multiple Choice

When the northern hemisphere is tilted away from the Sun, what season is it in Texas?

• summer

• winter

• spring

• fall

Multiple Choice

When the Northern Hemisphere is tilted away from the Sun

• the South Pole is pointing directly at the Sun

• it is summer in the Southern Hemisphere.

• it is night in the Northern Hemisphere.

• the Sun's rays do not strike the Northern Hemisphere.

Multiple Choice

Earth would not have seasons if it...

• no longer tilted on its axis

• stopped rotating on its axis

• took an additional month to orbit the sun

• revolved around the sun in the opposite direction

Multiple Choice

The picture shows a globe of the world with Barrow, Alaska circled. For almost three months, mid-May to mid-August, the Sun never sets in Barrow, Alaska. 

Which is the most likely reason for the Sun always shining in the summer in Barrow? 

• Earth only rotates on its axis during the winter, so the same part of Earth faces the Sun all summer

• Only the middle of the Earth rotates around its axis, so the top of Earth always faces the Sun

• Earth's axis is tilted, so some of the time parts of Earth face the Sun for the entire daily rotation

• The Sun's axis is tilted, so some of the time parts of Earth face the Sun for the entire daily rotation

Multiple Choice

The picture shows a globe of the world with Barrow, Alaska circled. For almost three months, mid-May to mid-August, the Sun never sets in Barrow, Alaska. 

Which is the most likely reason for the Sun always shining in the summer in Barrow? 

• Earth only rotates on its axis during the winter, so the same part of Earth faces the Sun all summer

• Only the middle of the Earth rotates around its axis, so the top of Earth always faces the Sun

• Earth's axis is tilted, so some of the time parts of Earth face the Sun for the entire daily rotation

• The Sun's axis is tilted, so some of the time parts of Earth face the Sun for the entire daily rotation

Are there any questions?

​

​Exit Ticket Time!

Multiple Choice

The diagram depicts Earth moving around the sun.  The name for Earth's motion is

• rotation

• revolution

• turning

• spinning

Multiple Choice

Northern Hemisphere...

• the top half of Earth from the equator up

• the bottom half of Earth from the equator up

• the left half of Earth from the equator up

• the right half of Earth from the equator up

Multiple Choice

When at position 2, the northern hemisphere is in

• summer

• fall

• winter

• spring

Open Ended

At position two, the Earth is in which season? How do you know?

Multiple Choice

Southern Hemisphere...

• the bottom half of Earth from the equator down.

• the top half of Earth from the equator down.

• the left half of Earth from the equator down.

• the right half of Earth from the equator down.

Multiple Choice

When at position 2, the southern hemisphere is in

• summer

• fall

• winter

• spring

Multiple Choice

When the northern hemisphere is tilted away from the Sun, what season is it in Texas?

• summer

• winter

• spring

• fall

Multiple Choice

Season...

• one of four periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

• one of three periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

• one of two periods of the year (spring, summer, autumn and winter) that have particular conditions of weather and temperature.

Multiple Choice

Bottom box represents which season in Norhtern hemisphere?

• summer

• winter

• spring

• fall

Multiple Choice

top box represents which season in the Northern hemisphere?

• summer

• winter

• spring

• fall