Why are the poles colder than the equator?

It is easy to know that each part of the world has its own climate. In general, it is true to say that the poles are colder than the equator. This results from the earth‘s tilt, the warmer receive more direct sunlight.

The earth is sphere- shaped with the tilt of a slope of 23^o29’. Additionally, the Sun is more directly positioned over the Equator. Therefore, when the sun rises, the middle part of earth – the equator- have more direct light and then is warmer than the poles. The average temperature of the equator areas is about 25-30 ^oCelcius while the degree at the poles is often negative, which makes it harder for the plants and animal to survive here. Furthermore, the humidity of the equator is higher. This helps plant more green .