How does the earths tilt cause the seasons?

Question

I'm confused how it all works. Please clarify

Answer 1

The earth is tilted on it's axis, relative to the plane of it's orbit around the sun. One complete orbit around the sun is one year (i.e. the four seasons). The earth is tilted differently relative to the sun at different points on it's orbit, because the earth's tilt position stays the same as it orbits the sun.

When the earth is on one side of it's orbit, the northern hemisphere is tilted toward the sun and the southern hemisphere is tilted away from the sun. On the opposite side of it's orbit, vice versa: the northern hemisphere is tilted away from the sun and the southern hemisphere is tilted toward the sun.

On the two points on the earth's orbit halfway between those two previous points, the earth is tilted in line with it's orbital path - neither hemisphere is tilted toward or away from the sun.

(1) Any point on the earth spends a greater or lesser portion of the earth's daily rotation (24 hrs) in sunlight, depending on whether that part of the earth is tilted toward or away from the sun at that time of year. (2) The angle of the suns rays hitting that point on the earths's surface also depends on how the earth is tilted realative to the sun at that time of the year.

The closer the angle of the sun's rays with the earth's surface is to 90 degrees (i.e. sun directly overhead in sky) and the longer the place spends in sunlight, the hotter the days. The lower the angle of the sun and the smaller the amount of time spent in sunlight each day, the colder the days. The hotter times are summer and the coldest times are winter.

This is why there are different seasons at the same time in the northern and southern hemispheres - one is tilted toward the sun while the other is tilted away.

To picture this, get a globe of the earth (which will be tilted on it's stand) and get a table lamp and take the shade off of it. Hold the globe in the positions I've described above, without turning the base stand of the globe relative to the room or table - i.e. so it is always tilted in the same direction, but the direction of tilt changes relative to the light. Spin the globe in each position and note one place on the globe in both north and south hemispheres - (1) the portion of one spin it stays in the light and is in darkness and (2) the angle at which the light hits the globes surface there..

Answer 2

It changes the angle of the sun from the perspective of the higher latitudes. Increasing or decreasing the amount of sunlight that is absorbed versus the amount that is just bounced back into space.

It also increases or decreases the length of the days and nights, longer days in summer, longer nights in winter. It alters the proportion of the light and dark in the 24 hour day. Think of it as a slow moving hemisphere of light independent from the earth's spinning, the tilting of the axis alters how long a given point will spend in or out of the hemisphere.

At the poles the summer and winter solstices are marked by several weeks of unbroken daylight or darkness. Because the poles are tilted in and out of the hemisphere of light as the year progresses.

Answer 3

I'm assuming you are living in the northern hemisphere.  Look through the sources below for additional information.  Also, if you get yourself a globe or basketball (mark a N and S pole), go into a dark room, turn on a flashlight and let it rest on its side on a counter top, it may help for you to see what's going on.

One thing you have to understand is because their Earth is tilted about 23.5 degrees from the vertical plane and because the Earth spins on its axis, the direction of the Earth's tilt doesn't change (that is part of the reason why the North star is always the same).  

During the summer, the northern hemisphere of the Earth is pointed towards the sun.  So during this time, the Northern Hemisphere is receiving more hours of light and more direct sunlight.  For example, during the summer, you should notice that there are more than 12 hours of sunlight and if you go out at noon and notice your shadow, it should be fairly small.

During the winter, the northern hemisphere is pointed away from the sun.  So during this time, the Northern Hemisphere is receiving fewer hours of light and the light is not as direct.  For example, during the winter, you should notice that there are fewer than 12 hours of sunlight and if you go out at noon and notice your shadow, it will be fairly long.

The reverse happens if you live in the Southern Hemisphere.