The Reason for the Seasons

Slides:



Advertisements
Similar presentations
The Reason for the Seasons
Advertisements

Season Vocabulary Seasons – A pattern of temperature changes & other weather trends over a year.
What’s The Reason For The Seasons?
It’s the Tilt, Not the Distance
Warm-UP NoteBook – ORGANIZE Earth, Moon and Sun Study Guide Vocabulary
What causes the Seasons?
Earth’s Days, Years, and Seasons
Seasons Seasons are periods of time over the course of a year during which certain weather conditions prevail. Climate describes the average weather conditions.
Today’s Agenda… Bellringer: Identify each as rotation or revolution (this is not multiple choice) A. Takes 24 hours B. Spins on Axis C. Takes 365 ¼ days.
The Earth and its Motions
What Causes the Seasons?
The Reason for the Seasons
Why is it so hot here in the summer?. The Earth in Space TEK 8.7A – the student knows the effects resulting from cyclical movements of the Sun, Earth,
Space Cycles Moon Phases Seasons.
Page #136 Feb. 5, 2013 Focus: Day & Night, Seasons, Rotation & Revolution Objective: explain how the movement of the Earth affect different cycles EQ:
Solar Motion. Label front flap MOTIONS OF THE EARTH -DAY & NIGHT.
Earth’s Motion and Seasons
To an observer on Earth, the bright and dark portions of the moon appear to change shape during each phase. The diagram, however, shows that during each.
Unit 3 Lesson 1 Earth’s Days, Years, and Seasons Copyright © Houghton Mifflin Harcourt Publishing Company.
Earth-Moon-Sun Cycles. Cycle # 1 Day and Night Day  Night  Day  Night.
Seasons. What Causes Seasons? Seasons are caused by the tilt of the earth’s axis as it moves around the sun. Seasons happen because the Earth is tilted.
Earth’s Seasons. Rotation 1.The imaginary line that passes through Earth’s center and the North and South poles is called Earth’s axis. 2.Earth spinning.
Days, Years & Seasons. Days and Nights Rotation: the Earth turns around on its axis 1 day=24 hours (one rotation) One half of the Earth is always in light.
Earth/Sun Relationship. Temperature The condition of the atmosphere at a given place and time.
Do Now  Copy down your Learning Target on page  What do YOU think causes seasons?
What causes seasons? The tilt of the Earth on its axis The 23.5° tilt is caused by the interaction between the Moon and the Earth.
Seasons on Earth Two reasons the Earth has seasons: 23.5 degree tilt
 Reasons for the Seasons Subject: Science Topic: Astronomy.
SEASONS and the Earth’s Axis
Earth’s Orbit 4/29/14 IN: What causes the different seasons on the Earth? IN: What causes the different seasons on the Earth?
They are caused by Earth’s orbit around the sun and the way that Earth tilts on its axis.
The Moon & Earth’s Tilt. What is the Moon? A large rock that orbits a planet The Earth has 1 moon Moons orbit planets Planets orbit the sun.
Reasons for the Seasons
Seasons Patterns of temperature changes and other weather trends over the course of a year are known as seasons. Spring Vernal Equinox March 20,21 Which.
The Reason for the Seasons
Climates, Seasons, & Days
Reasons for the Seasons
Earth’s Physical Geography Chapter 2, Section 1. Our Planet, the Earth The Earth, sun, planets, and stars are all part of a galaxy, or family of stars.
Earth in Space. How Earth Moves Earth moves through space in two major ways: rotation and revolution.
The Reason for the Seasons The explanation of the beautiful changes that occur on Earth from season to season lies in the movement and position of the.
What Causes Seasons?. We know that the reason we have day and night is because the Earth rotates. Rotate means to turn. The Earth rotating on its ______.
How do we get our seasons?. The AXIS is important! The axis is the imaginary line through Earth from the North Pole to the South Pole. The earth spins.
Let’s Review.  A location’s latitude determines its temperature trend during the year.  Locations at or near the equator experience very little change.
Seasons. Seasons happen because of Earth’s tilt on its axis AND revolution around the Sun. Axis- imaginary line drawn from the north to the south pole.
The Reason for the Seasons. #1 Here’s Mars… Where would you guess that it is COLDEST on Mars? If you guessed here… …and here… …you’re right. But why?
How rotation, revolution, and tilt cause it all!.
Write down what comes to mind when you think about Earth’s days, years, and seasons.
Before, you learned Stars seem to rise, cross the sky, and set because Earth turns The Sun is very large and far from Earth Earth orbits the Sun Now,
The Effects of the Rotation of the Earth
Seasons Page 520.
Reasons for the Seasons
Reasons for the Seasons
Seasons Why do we have them?.
The Reason for the Seasons
Why is it so hot here in the summer?
TEMPERATURE, SEASONS, SOLTICES, and equinoxes
The Reason for the Seasons
Seasons Vocabulary Summer Northern Hemisphere
Unit: Space Topic: Seasons Page: #
Aim: What causes Seasons?
Notes Seasons.
Cornell Notes 1.2 Seasons September 13, 2017 – Page 15.
Time of the Seasons We have seasons because of the tilt of the Earth’s axis. The Ecliptic appears tilted 23.5° from the Celestial Equator because Earth’s.
Earth’s Movements through the Solar System.
Why Do We Have Seasons?. Why Do We Have Seasons?
Seasons Page 520.
Seasons.
The Effects of the Rotation of the Earth
The Reasons for the Seasons
Presentation transcript:

The Reason for the Seasons School's Out! Brrrrrrrrrr! Leaves go down!

Here’s Mars… Where would you guess that it is COLDEST …you’re on Mars? right. But why? And how did you know? If you guessed here… …and here…

sunlight comes in from just one direction Half of Jupiter lit by the Sun light

It’s all about the angle at which the light hits the planet! Venus, lit by the Sun Look at a ray of sunlight hitting the middle of the planet. The ray hits this part of the planet directly at a 90 degree angle. It focuses the sun’s energy (heat) over a relatively small area.

But at the north & south pole? Here comes a second ray from the sun toward the south pole of Venus. Notice it hits Earth’s surface at a angle that is much less than 90 degrees. the direct ray of light Notice how much LARGER an area the ray covers…this means it’s LESS concentrated (or more spread out).

So direct light heats planets up more than indirect light! Around the middle of the planet, the sun’s rays hit Earth directly, so the energy is more concentrated. There is more energy per unit area and the Earth heats up a relatively greater amount. But at the top and bottom of the planet, the light comes in at a less direct angle, meaning the energy is less concentrated. It is spread over a greater area and therefore does not warm the planet as much.

So that explains why… Up here we have…

…and… Around here we have…

…and… Down here we have… I’m cold

This helps, but it doesn’t explain the seasons! So far we only know why the hottest part of each planet is around the middle…the sunlight hits that part most directly. If that was all that happened, though, we WOULDN’T have different seasons…just the same boring weather all year long. In Texas, it’d be about 90 degrees every day of the year with occasional rain. Not bad, but definitely BORING.

This is the key, so repeat after me… It’s… the… TILT

The Earth doesn’t sit perfectly straight up and down A “false” view of Earth rotating on its axis. This just isn’t right!

#13 Our Axis is TILTED! TILT About 23.5 degrees

A more accurate view… Notice the… TILT

Remember from earlier… …That the middle of the planet gets the most direct sunlight (heat). COLD medium HOT

So one half of the Earth “tilts” toward the sun! What does the tilt do? Direct light = Summer! Indirect down here = Winter! Which hemisphere of Earth (Northern or Southern) is having Summer & Winter in this diagram?

Scientists believe that the sun and the eight planets formed by chunks of rock and debris that self-accumulated through gravity. In other words, objects collided and clumped together, which increased their gravitational pull, which in turn drew more objects in, which made the object even more gravitationally powerful, and so on until the solar system looks like a sun and eight fairly neat planets with not much stray junk flying around. 

http://www.express.co.uk/life-style/science-technology/374662/Asteroid-armageddon-Earth-to-have-near-miss-next-month-but-risks-impact-in-2020 Of course, occasionally these forming objects happen to attract something that's big enough to knock it off-kilter. That's what probably happened to the earth, after it was already large enough to start rotating. Actually, it probably took several substantial impacts to whack the earth into the position it's in today. 

What does this mean for Texas? When our Northern Hemisphere tilts toward the Sun, we actually get nearly the most direct sunlight of anywhere on the planet! No wonder we get over 100 degrees so often in July & August!

So…how do we get Winter here??? That happens when our (Northern) hemisphere tilts away from the sun. Summer down here!

And the final piece to the puzzle? So, the TILT is a big part of it, but something else must cause us to tilt either away or toward the Sun at different times during the year… …and that last bit is something you’ve known for years! The Earth revolves around the Sun! Watch the animation…pay attention to the direction Earth’s axis points as it orbits the Sun.

So it’s a combination of the TILTed axis and our revolving around the sun! Yeah!!!

Complete the table 4 1 3 2 A hemisphere is experiencing summer if it is tilted directly toward the sun. A hemisphere is experiencing winter if it is tilted directly away from the sun.

Seasons Animation http://esminfo.prenhall.com/science/geoanimations/animations/01_EarthSun_E2.html

Misconceptions about the Seasons 1. We experience seasons because Earth is closer to the sun in the summer and farther in the winter. WRONG Actually, the opposite is true. We are closer to the sun in the winter (91million miles away) than we are in the winter (94 million miles away). If this were true, wouldn’t Hawaii experience snow?

Notice the distance during the summer!

Why do we experience day and night? The Earth is… Rotating

Day versus Night When where you are is pointed toward the Sun, it is day. Then the Earth rotates you away from the Sun, and it is night. Sunlight Daytime Nighttime

Day and Night as the Earth is rotating on its AXIS

Northern Hemisphere Summer Southern Hemisphere Winter Hemispheres experiencing summer receive MORE DIRECT RAYS from the sun than hemispheres experiencing winter. This direct light as its tilted towards the sun keeps the hemisphere ILLUMINATED for a greater amount of time during the day.

Length of Day in Hemispheres 4 1 2 3 #1 June Day length England (Northern Hemisphere) - 15 hours and 38 minutes Australia (Southern Hemisphere) - 10 hours and 24 minutes

The Earth reaches 4 important points in its orbit 1 2 3 Position 1: June Solstice About June 21st TX tilted toward Sun We have our longest day, shortest night Begins Summer

Three months later… Position 2: September Equinox About September 23rd 4 1 2 3 Position 2: September Equinox About September 23rd TX tilt in between “toward” and “away” 12 hrs day, 12 hrs night Begins Fall

#23 Three months later… Position 3: December Solstice 4 1 2 3 Position 3: December Solstice About December 22nd TX tilted away from Sun Shortest day, longest night Begins Winter

Three months later… Position 4: Vernal Equinox About March 21st 3 Position 4: Vernal Equinox About March 21st TX tilt half way between “toward” and “away” 12 hrs day, 12 hrs night Begins Spring

So, In Summary… If somebody asked you, “Why do we have seasons on Earth?” you could now answer with great confidence… Fact 1: Round planets heat up wherever they get direct sunlight and are cooler at the tops and bottoms. Fact 2: The Earth’s axis is TILTED 23.5o. Fact 3: As Earth revolves around the Sun, the tilt causes different parts of it to receive more or less direct sunlight for a few months, causing the weather and daylight to change.

The End!