Remember Yesterday? The seasons/climate depend on your location on Earth (latitude)

Why do changes in latitude affect seasons? It’s all about the sun 

Let’s think about light What is light? Where does our light come from? How does light affect temperature? Think about our daily temperature graphs from Friday.

A Little Background on Light Light rays move in straight lines (that’s why we have shadows) Light from the sun makes a parallel beam of light on the entire Earth. Light that strikes at a steep angle warms more than light that strikes at a shallow angle. How much an objects temperature increases depends on how intense the light is striking its surface, how long it shines on the object, and how much of the light is absorbed.

Let’s Review Light Which one is going to be hotter/more intense?

What does that mean for summer? Connect light angles to the season summer.

Earth’s Tilt During the Summer We have more direct light (the sun is higher in the sky) Season’s happen at different times around the Earth (remember our climatographs) For the regions in the northern hemisphere… when is summer? For the regions in the southern hemisphere… when is summer? How can light angles be direct on both places but at different times? Earth’s Tilt

Earth’s Tilt: 23.5⁰

How does Earth’s Tilt Affect Light Intensity? Would light be more intense in a spot on Earth that is tilted TOWARDS the sun or AWAY from it?

Let’s Review Tilt How much is the Earth tilted? 23.5⁰ Why does the Earth’s tilt matter? It changes the angle of light that hits the Earth and where the Earth gets the most “direct” light.

What Season You’re in Depends on… What part of the Earth you’re at (northern hemisphere, southern hemisphere, equator, etc.) Where the earth is in its revolution. What do you notice about Earth’s tilt? It’s always pointed THE SAME DIRECTION If you live in the Northern Hemisphere, which part of the Earth’s revolution is SUMMER? Which one is Winter? What are the other two?

Earth’s Revolution How many days does it take the Earth to REVOLVE around the sun? 365 ¼ days What happens to that ¼? LEAP YEAR! 

What if We lived in the Southern Hemisphere? Fall Winter Summer Spring

Fall Spring Summer Winter Winter Fall Spring The Seasons Summer Northern Hemisphere Southern Hemisphere Fall Spring Summer Summer Winter Winter Fall Spring

What Causes the Seasons?

During the summer… How is the earth tilted? Towards the Sun

During the Winter… How is the Earth Tilted? Away from the sun.

What about Fall and Spring? The earth isn’t tilted towards or away from the sun.

Let’s Practice Try not to use your notes, this is not for a grade it’s to tell me if you understand it

Fill in the last piece of your notes The Earth’s tilt matters because_______________________.

Now, what causes seasons? Latitude: where you are on the earth affects the angle of light that hits you Angle of light: light that strikes at a steep (direct) angle warms more than light that strikes at a shallow (indirect) angle Earth’s tilt and revolution: Earth’s tilt changes where light is the most direct and it’s revolution changes which part of the Earth is pointed towards and away from the sun. There’s one more thing, but we’ll cover that tomorrow