Why doesn't it snow in Houston on Christmas?
Written and Illustrated by Jolene Foust
The Seasons change every 3 months. There are 2 main causes for the change of seasons.
1. The axis of the earth is tilted 23.5 degrees.
2. The Earth revolves around the sun once a year.
What is a season?
A season is a subdivision of the year. We have four seasons on earth: spring, summer, fall, and winter.
During seasons, hours of daylight and weather may vary greatly depending on your location on earth.
First day of each season:
The first day of winter is called the Winter Solstice. It is usually between December 20th and 22nd.
The first day of spring is the Vernal Equinox. It is usually between March 20th and 22nd.
The first day of summer is the Summer Solstice. It is usually between June 20th and 22nd.
The first day of autumn is the Autumnal Equinox. It is usually between September 20th - 23rd.
During the winter the earth is titled away from the sun and daylight hours are fewer than night hours.
During the summer the earth is titled toward the sun and the daylight hours are more than the night hours.
In spring and fall the daylight and night hours are almost equal and temperatures are generally mild.
When the Sun is overhead, the light is falling straight on you, and so more light (and more heat) hit each square centimeter of the ground. When the Sun is low, the light gets more spread out over the surface of the Earth, and less heat (per square centimeter!) can be absorbed. Since the Earth's axis is tilted, the Sun is higher when you are on the part of the Earth where the axis points towards the Sun, and lower on the part of the Earth where the axis points away from the Sun.
In the summer, the Sun is higher, and therefore the days are longer. This gives the Sun more time to heat the Earth, so it gets hotter. In the winter, the sun is lower, and the days are short, giving the Sun less time to heat the Earth.