Week 5
What effect does the Earth's tilt have?
What effect does the Earth's tilt have?
I can understand how the relationship between the tilt of the Earth's axis and its revolution around the Sun influence the changing seasons experienced on our planet.
I can explain the cause Earth's seasons using technical vocabulary
I can clearly describe how the tilt of the Earth's axis affects the angle and intensity of sunlight received at different times of the year, leading to the variations in seasons.
I can accurately outline how the Earth's orbit around the Sun causes different hemispheres to experience varying seasons due to their changing position relative to the Sun.
I can use the following words in descriptions of the Earth's motion: axis, tilt, rotation, revolution, orbit, equinox, solstice, hemisphere, ellipse, perihelion, aphelion
Knowledge & understanding
Investigating Seasons hyperdoc on Google Classroom
Investigation Skills
Prac: Investigating the relationship between angle of light and intensity
Literacy & research
Whole class activity: Explaining misconceptions
Knowledge & understanding
Many people think seasons are caused by Earth being closer to the Sun at that time of year. It is true that Earth has a slightly elliptical (oval shaped) orbit and that at some times of the year it is closer or further from the Sun. However, as it turns out, we are closest to the Sun when it is winter in the Northern Hemisphere and summer in the Southern Hemisphere. So, if it is summer and winter at the same time, there must be something else responsible for our seasons.
This diagram shows a very exaggerated shape of Earth's orbit; the actual orbit is almost circular.
Earth is a bit like a wheel which spins around in circles around a central axle. Here the “axle” is called Earth’s axis and instead of spinning around a horizontal axle like wheels, Earth currently has a tilt of approximately 23.5 ° from vertical. The Earth makes one complete turn each day. As Earth orbits the Sun it spins on its axis, giving us day and night.
The Earth’s tilt remains consistent throughout a year’s journey around the Sun, pointing towards the same position in space. The North Pole consistently points towards the North Star (Polaris). Scientists believe that a large object called Theia collided with Earth not long after it formed which caused the Earth to tilt.
Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive more sunlight than others and that sunlight is more concentrated. When one pole tilts towards the Sun, itreceives more sunlight, which is also more concentrated, while the opposite pole tilts away from the Sun giving it less sunlight, which is also more dispersed.
So, when the North Pole tilts toward the Sun, it is summer in the Northern Hemisphere and winter in the Southern Hemisphere, and when the South Pole tilts toward the Sun, it is summer in the Southern Hemisphere and winter in the Northern Hemisphere. It is summer in December in the Southern Hemisphere because more of the Sun's rays hit that part of Earth more directly than at any other time of the year. You should note at this time of year the Sun is more directly overhead at midday, days are longer and therefore there is a much greater heating effect on the Southern Hemisphere.
Investigation Skills
Literacy & research
Explain why the following are misconceptions:
Misconception #1: Earth's orbit brings it closer to the Sun in summer and farther away in winter.
Misconception #2: Earth is tilted 23.5 degrees on its axis and the hemisphere that is tilted toward the Sun experiences summer because it is closer to the Sun.
Misconception #3: The shortest day of the year is also the coldest