Учебный проект Времена года-2/Работа учащихся

Автор

учащиеся 4 "А" класса МКОУ Заводская СОШ

Проблемный вопрос

Почему времена года сменяют друг друга?

why do the seasons follow each other?

Гипотеза исследования

Seasons happen because the Earth's axis is tilted at an angle of about 23.4 degrees in relation to its path around the Sun.

Исследование

Regardless of the time of year, the northern and southern hemispheres always experience opposite seasons. This is because during summer or winter, one part of the planet is more directly exposed to the rays of the Sun than the other, and this exposure alternates as the Earth revolves in its orbit. For approximately half of the year (from around March 20 to around September 22), the northern hemisphere tips toward the Sun, with the maximum amount occurring on about June 21. For the other half of the year, the same happens, but in the southern hemisphere instead of the northern, with the maximum around December 21. The two instants when the Sun is directly overhead at the Equator are the equinoxes. Also at that moment, both the North Pole and the South Pole of the Earth are just on the terminator, and hence day and night are equally divided between the northern and southern hemispheres. At the March equinox, the northern hemisphere will be experiencing spring as the hours of daylight increase, and the southern hemisphere is experiencing autumn as daylight hours shorten.

The effect of axial tilt is observable as the change in day length and altitude of the Sun at noon (the culmination of the Sun) during a year. The low angle of Sun during the winter months means that incoming rays of solar radiation are spread over a larger area of the Earth's surface, so the light received is more indirect and of lower intensity. Between this effect and the shorter daylight hours, the axial tilt of the Earth accounts for most of the seasonal variation in climate in both hemispheres.

Выводы

It’s logical to assume our planet’s changing distance from the sun causes the change in the seasons. But Earth’s distance from the sun doesn’t change enough to cause seasonal differences. Instead, our seasons change because Earth tilts on its axis, and the angle of tilt causes the Northern and Southern Hemisphere to trade places throughout the year in receiving the sun’s light and warmth most directly.

Литература

1.Cain, Fraiser. "Tilt of the Earth". Retrieved 2 May 2014.

2.Phillips, Tony. "Earth at Perihelion". Science News. NASA. Retrieved 14 May 2013.

3.http://earthsky.org/earth/can-you-explain-why-earth-has-four-seasons