what is the scientific explanation for seasons?

Answer 1

Seasons reasons
Unless you live near the Earth's equator, you have no doubt noticed that the weather changes during the year: it is hotter during the Summer, colder in Winter, and somewhere in between during Spring and Fall. These are the seasons, a regular change in temperature, that repeat themselves every year, more or less regularly.

What causes these changes? The Sun is our main source of heat, and since these changes are the same every year, it surely has something to do with the movement of the Earth around the Sun. If we get closer to a fire, we get hotter. Could it be then that the Earth gets closer to the Sun during Summer, and farther during Winter? This idea seems at first to have some merit, until we remember that the seasons get reversed when we cross the equator: when it is Summer in the northern hemisphere, it is Winter in the southern one, and vice versa. And surely Argentina is at the same distance from the Sun as the USA!

Besides, that the Earth's orbit is an ellipse, not a circle, so that at some times the Earth is closer to the Sun than at others; but this ellipse is very nearly a circle, and the relatively small differences in distance to the Sun cannot account for the changes in temperature. And to make things worse, the Earth is closer to the Sun during the northern hemisphere Winter!

What, then, is, the cause of the seasons?



In the above animation, you can see the Earth during one full year (the animation then starts over again), as you would if you looked straight at it from the Sun. As you can see, the part of the Earth that is directly facing the sun changes with the time of the year. It is the northern half for a while, then moves south of the equator, only to move back to the north again.

What causes this? The Earth rotates around an imaginary line passing through the poles, called the axis. This line forms an angle (called the tilt) of 23.4° with the perpendicular to the orbit of the Earth around the Sun.




As the Earth moves around the Sun, this axis stays always pointing in the same direction. This means that, during part of the year, the northern part of the Earth will lean more directly against the sun, and during other parts the southern part will.

What has this to do with temperature? Well, when the northern hemisphere is leaning away from the sun, the rays coming from it hit this part of the Earth at a smaller angle than on other parts of the world. This means that the same amount of light is distributed over a larger surface, and therefore these places receive less heat than the others. The southern hemisphere is experiencing Summer, the northern hemisphere Winter. In half a year, the situation reverses, and it is now Winter in the southern hemisphere since that part of the earth is now leaning away from the sun.

The seasons are then the result of this tilt of the Earth's axis. If the tilt of the Earth's axis was 0° there would be no difference in how the rays from the sun hit its different regions, and there would be no seasons.

Not all planets have the same kind of tilt as the Earth has: Uranus, for example, has a tilt of almost 98°. Its axis, then, lies almost on the plane of its orbit, and a day there lasts about as much as one year on Uranus: about 84 Earth-years.

Answer 2

Go with Pam's answer. It is the best explained answer that you could get since it brings all 3 factors into play--the rotation of the earth around the sun, the rotation of the earth on its axis & the tilting of the earth's axis. It's the most thorough & consise explanation I have seen in a long time--it's a winner

Answer 3

In the temperate and polar regions, seasons are marked by changes in the amount of sunlight, which in turn often cause cycles of dormancy in plants and hibernation in animals. These effects vary with latitude, and with proximity to bodies of water. For example, the South Pole is in the middle of the continent of Antarctica, and therefore a considerable distance from the moderating influence of the southern oceans. The North Pole is in the Arctic Ocean, and thus its temperature extremes are buffered by the presence of all that water. The result is that the South Pole is consistently colder during the southern winter than the North Pole during the northern winter.

The seasons result from the Earth's axis being tilted to its orbital plane; it deviates by an angle of approximately 23.5 degrees of arc. Thus, at any given time during the summer or winter, one part of the planet is more directly exposed to the rays of the Sun (see Fig. 1). This exposure alternates as the Earth revolves in its orbit. At any given time, regardless of season, the northern and southern hemispheres experience opposite seasons (see Fig. 2 and Month ranges of seasons (below) and Effect of sun angle on climate).

Seasonal weather fluctuations also depend on factors such as proximity to oceans or other large bodies of water, currents in those oceans, El Niño/ENSO and other oceanic cycles, and prevailing winds.

The cycle of seasons in the polar and temperate zones of one hemisphere is opposite to that in the other. When it is summer in the Northern hemisphere, it is winter in the Southern hemisphere, and vice versa, and when it is spring in the Northern hemisphere it is autumn in the Southern hemisphere, and vice versa.

In the tropics, there is no noticeable change in the amount of sunlight. However, many regions (famously the northern Indian Ocean) are subject to monsoon rain and wind cycles. Curiously, a study of temperature records over the past 300 years (David Thompson, Science, April 1995) shows that the climatic seasons, and thus the seasonal year, are governed by the anomalistic year rather than the tropical year.

In meteorological terms, the winter solstice and summer solstice (or the date maximum/minimum insolation) do not fall in the middle of winter and summer respectively. The heights of these seasons occur up to a month later due to seasonal lag. Seasons though, are not always defined in meteorological terms; see reckoning

Compared to axial tilt, other factors contribute little to seasonal temperature changes. It's a common misconception that the seasons are the result of the variation in Earth’s distance to the sun due to its elliptical orbit.[1] Orbital eccentricity can influence temperatures, but on Earth, this effect is small and is more than counteracted by other factors; research shows that the Earth as a whole is actually a few degrees warmer when farther from the sun.[2] Mars however experiences wide temperature variations and violent dust storms every year at perihelion.[3]

You could get more information from the link below...

Answer 4

Seasons are due to the tilt of the earth' axis with respect to the plane of its orbit around the sun. The full explanation is here:
http://en.wikipedia.org/wiki/Seasons

Answer 5

this ability there substitute into an underworld eclipse on the time of the suns 2d roatation 44hours and 43min and 21 secound as a results of upward push of the only eyed abode groper. Or it may be which you going schitzo?

Answer 6

Quite simple,
Its the movement of Mass (earth) around the main life force, The Sun, the rotation and swings put us nearer or farther from it.
Paul

Answer 7

earth is moving araund the sun, as you know.
but its route is an oval.so the distance between sun and earth changes . summer is the situation which earth is the nearer to
the sun.and the winter is the situation which the earth is farther.

Answer 8

each weather seasons is a different is closer to the sun and

Answer 9

unpredicted chemical reactions