Why does earths tilt affect seasons?
So i lve been told that earths tilt changes seasons due to the hemisphere in question receiving more light directly due to the tilt. Bear with me as i may be misunderstanding, but wouldnt the surface area facing the sun remain the same? Its just tilted and now on an angle so what is causing the temperature change,...
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answers:
Tom S say: No, the surface area facing the sun does not remain the same, at a low angle it is "spread out" more. It is for the same reason that it is cooler at sunrise and sunset than near mid day when the Sun is high. The atmosphere does have some effect in absorbing and retaining heat, but Mars for instance has a very thin atmosphere, but still has seasons for the same reason.
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quantumclaustrophobe say: So, during summer in the northern hemisphere, our day length increases, and the sun's angle is far more direct - which means it's light and energy doesn't have to travel through (and be absorbed by) more atmosphere; the result is heating of the ground and ocean.
At the same time, in the southern hemisphere, the day is much shorter, while the sun's light is much less direct - removing energy from the sun's light before it's able to heat the ground or water.
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sparrow say: Because it can tilt toward the sun, or it can tilt away from the sun.
Depending on where it is in it's yearly orbit around the sun.
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Clive say: The tilt CAUSES seasons. If the Earth's axis was exactly vertical compared to its orbit round the Sun, the Sun would always rise to the same height in the sky every day and there would be no seasons.

Yes, the surface area facing the Sun is always half of the planet, But as the Earth moves round the Sun, WHICH half is facing it? And where are you in that lit-up half? That's the thing! It changes day by day because of the tilt.

In summer, where you are is tilted more towards the Sun, so it's more towards the middle of the lit-up half and it will be lit up for longer. So there is an earlier sunrise, a later sunset, it rises more directly east and sets more directly west, the Sun rises higher in the sky, and that all makes for hotter days - you get more sun for more time, and nights are shorter so there is less time for cooling down before we get sunrise again. In winter, it's the opposite - you're more towards the edge of the lit-up half because of the tilt, so days don't last so long, and the Sun doesn't get so high in the sky and not for so long. It has less chance to warm you up.

Have you noticed that - the Sun gets higher in the summer? The tilt does that. I certainly notice as I sit here at my computer. I'm next to a window and in summer, the Sun gets so high it misses the top of the window, I just get light coming in. But on winter mornings, the Sun doesn't get high enough to miss the window, so I have to draw the curtains to stop direct sunlight getting in my eyes. Meanwhile my relatives in Australia are getting their turn to have summer.

I'm at 52 degrees north so the day length is quite significantly different between summer and winter. When I went out to work, I didn't see my house in daylight in winter except at weekends!

Let's go even further north or south - there will be times in summer when you're in the lit up half 24/7 so there is the Midnight Sun, and times in winter when you're permanently in the dark. Actually at the poles, you get 6 months of day followed by 6 months of night. No wonder they're freezing cold!

So think about this one - there is an American research base actually at the South Pole, and how do they measure days? What they do is totally ignore what's going on outside and just pick a time zone - it hardly matters which, when a real day there is 1 year long. Whatever you do to get a normal 24 hour day will not match the outside world. In fact they use New Zealand time, because it's the nearest country to fly from and to so scientists always go there via NZ. It's as good a choice as any and makes that stage of the trip to or from home simpler.
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Fred say: #1. You have traveled North in any season and noticed that the days or nights are noticeably colder in temperature?

You have traveled South and noticed that the days or nights are noticeably warmer in temperature?

Let's pick St. Louis, Missouri and you travel South to Baton Rouge and by a miracle the humidity is exactly the same. Notice as you go closer to the equator the temperatures rise? Notice the daylength hours grow?

Now let's go North from St. Louis up to International Falls Minnesota, notice the temperatures drop? Notice the daylight hours are shorter?

The difference in latitude changes the Sun's angle in the sky. As you go South the Sun slowly climbs higher in the mid day sky and because the Sun is at a higher angle the path threw the sky is longer and the elapsed time from sunrise to sunset increases. As you go North the Sun makes a path lower and closer to the Southern Horizon. Also the elapsed time from sunup to sundown decreases.

If you constructed a box that was 12 inches by 12 inches and on the Equinox stood at midday and held the box in front of you the area on the ground inside the boxes shadow would measure 12 X 12 inches. If you took a plane up to Latitude 49 degrees International Falls the next day and held the box in front of you at noon so the shadow made the longest North-South box the square inside the shadow on the ground would measure 12 x 25.80 inches! The same unit of sunshine delivered to one square ft. of Earth at the equator is spread over more than twice the Earth at International Falls so each square inch receives less half the Suns energy that the equator receives!


#2. Now using this vast difference of sunlight the Earth's surface receives at those different locations think of the Earth back before some gigantic sub-planet collided with the Earth. Before collision the Earth was pristinely orbiting the sun with the Equator pointing squarely at the Sun in it's orbit. Along came a small sub-planet colliding with the Earth with such force that it tipped the Earth's geographic pole 23.40 degrees away from it's previous spin. The shattered fragments coalescing once again to a spherical Earth and far away particle clouds forming into a moon slowly coalescing from dust into a spherical satellite orbiting the ?Earth.

Now the Earth no longer has a center of rotation perpendicular to Sun obit, now one half cycle the Earth rotation axle is shifted 23.4 degrees to ward the Sun, the other half cycle of orbit the Earth's pole points 23.4 degrees away from the Sun. That's 46.8 degrees of sun apparent movement in the sky. That's 3.2 degrees less than International falls from the Equator difference in angle to sun.. and that shift of sunlight strike angle creates the Seasons!
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John say: (Mentally) Get a soccer ball and draw a circle around the center representing the equator. And get a flashlight. Put the flashlight on a place so it shines on the circle around the ball, and spin the ball. IF that were the Earth, there would be no seasons. Now, leave everything the same but tilt the ball at an angle of 23.5 degrees (30 deg will do). Now the light is shining on the northern or southern part of the ball, as the case may be. And as you spin the ball on it's axis that doesn't change. That is summer where the light is, and winter where it is not. If you take that ball and move it in a circle around the flashlight (and rotate the light with it), halfway around that "orbit" the light will reverse, and what was lit before will now be dark, and vice versa, and it will be summer in the opposite half and winter in the other.
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Ronald 7 say: As Earth orbits the Sun it carries its tilt along with it
At perihelion, the Arctic Circle faces away from the Sun in a 3 month Night
Whilst at the Antarctic Circle it has permanent daylight
At apehelion it is the other way around, with six months twilight in between
Being surrounded by more water and less actual land
More heat is reflected than Absorbed, making the Southern Hemisphere is generally cooler than its Northern Counterpart
the North Pole my be sea But it is surrounded by Russia, Canada, Baffin Island. Europe and Greenland
Antarctica has very little surrounding landmasses when you look from directly above and can only be matched by Siberia for low temperatures
-20 C is a balmy day there
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busterwasmycat say: the tilt changes direction relative to the sun, so north and south act as opposites. The total sunlight is more or less the same for the total earth, but the where on earth part changes. In summer, you are on the side where the tilt faces the sun so you get more of the sunlight, in winter you are on the side where the tilt is away from the sun.

For most of us, we see the difference in how high the sun gets in the sky. Where I live, noontime sun in dead of winter is only about as high as the sun would be in mid-late afternoon in the dead of summer. That intense 9AM-3PM sun of the summer never happens in winter.
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Gustave say: qglqcose
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yzjfo say: aysggyoo
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poornakumar b say: Consider Sun's angle as deviation (dip) from the zenith at local noon. If the Sun is above zenith as is the case within the Tropics of Cancer & Capricorn, maximum light is absorbed by the land there getting heated up in the day. If at an angle θ, the same light energy is spread on a larger area with light intensity proportional to 'Cosθ'. On June 21, Northern hemisphere tilts with Tropic of Cancer directly under Sun (θ = 0°) while on December 22, tilts away by θ = 2 x 23°.45. It amounts to about 1.41 times more area irradiated & intensity reduced to 0.707 times (as Cos 46°.9 = 0,707 = 1/1.41).
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say: Ahhhhhhhhhh
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james say: By warming & cooling the Pacific ocean do to tilt. It affects the oceans currents.& air currents. How strong they flow & were. Giving more power to 1 over the other. The air picks up moisture. in those currents. They drop when they cool as rain. Cool faster over land & mountains. This gives you the four seasons. wet, dry, wet, dry. The wet season is always cooler. Do to cloud cover. Normally 90 on cloudy days. 95 on sunny days with out cloud cover. As we catch both the easterly & westerly trade winds here. With the dolldrumbs between seasons or the dry season. There are also times when you get light rains for 3 days & nights. That are the cold fridget days here. Once to dropped al the way down to 70f here. We liked to die from the extreme cold that week. As homes here have no heat.
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Bill-M say: The Tilt is the CAUSE of the Seasons, not effect.
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poldi2 say: https://www.ducksters.com/science/season...
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CarolOklaNola say: The energy and power of sunlight CHANGES with the ANGLES that sunlight strikes surfaces. Maximum power and energy us Wyn sunlight hits a surface at a 90 degree angle. The Sun is at lower altitudes above the horizon and is above the horizon for fewer hours in the winter. during the summer, the Sun us above the horizon longer and reaches higher altitudes.

The angle of tilt stays the same, BUT the orientation if the Earth's rotational axis RELATIVE TO THE SUN CHANGES. That is the reason for the seasons. Earth is closest to the Sun on January 3 or 4.
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Dixon say: The Earth as a whole gets the same amount of sunlight all the time but given regions get different amounts of light throughout the year. Right now, the north end of the axis is tilted away from the sun, so for all the regions in the top half, the light falls at a shallower angle on the surface (ie the sun is low in the sky throughout the day) so it gets colder. Whereas in the southern half right now, the sun is more overhead and giving direct sunlight and it gets hot. So the north has winter and the south has summer.

Just to make sure you have the correct mental model, the axis of rotation always points in the same direction with respect to the distant stars. So when you see a globe and it has that tilt, you should imagine sliding the base of the globe in a big circle on the floor, representing orbiting the sun once per year, and the base always keeps the same direction with respect to the floor, and meanwhile and the Earth spins on the axle every day.

If you can picture that, there are four key locations on the orbit round the sun, the location where the axis' north end is away from the sun, the point where the northern end is toward the sun, and the mid points where both ends are equally "across" from the sun. The first two points give us mid summer/winter in the north/south. The second two mark the equinoxes when the north and south both get the same amount of sunlight and the day length is the same across the entire world.
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usben say: lhlrogyb
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Lord Bacon say: The tilt stays the same but the earth moves around the sun.
Half the time there is more of the Northern hemisphere exposed to the sun and half the time there is more of the Southern hemisphere exposed to the sun.
The surface area exposed to the sun remains the same but the location of that area moves as the earth moves round the sun.
That's what causes the seasons and explains why it is summer in Australia when it is winter in England.
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cirzr say: rxpbzlbz
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drake say: In the northern hemisphere during summer, sunlight hits the earth at an angle more vertically near the tropical and subtropical regions. Near the arctic circle and in the Southern Hemisphere, sunlight hits earth on an oblique angle to the perpendicular line to the ecliptic. This causes sunlight to be more spread out. If you were to observe a diagram, the earth’s tilt is just right where these regions are affected this way. It changes throughout the year. Near the equinoxes, the subsolar point intersects the equator. Sunlight in the northern and southern hemisphere hits the surface symmetrically causing the temperature to be similar in fall and winter for either hemisphere. Also, days are longer in the summer. This allows a longer time for the planet to heat up during the day.
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