Why the Seasons Change

Why do the seasons change? If you guessed the seasonal alteration has to do with the Earth's distance from the sun on its elliptical orbit, you guessed incorrectly. In fact, the primary reason is the 23.5 degree tilt of the Earth's axis, which causes the Northern Hemisphere to lean toward the sun for part of the year, resulting in the warmer temperatures of the summer months. Conversely, the Northern Hemisphere tilts away from the sun for part of the year, resulting in the colder temperatures of the winter months. As you can see in the diagram below, the Earth is actually closer in distance to the sun during the Northern Hemisphere's winter season; however the Northern Hemisphere is tilted away from the sun. Strange, huh?






Of course, when referring to seasons, it is important to remember that the Southern Hemisphere is different from the Northern Hemisphere; so when we are basking in the warm summer sun, those in the Southern Hemisphere are piling on their winter coats. Thus, while the Northern Hemisphere is tilted toward the sun (summer), the Southern Hemisphere is tilted away from the sun (winter).





The equator, however, is a different story. Close to the equator, the seasons do not change in the traditional sense; the equator’s two seasons are the wet season and the dry season. In reference to temperature, the equator is like one continuous summer, but due to the frequent rain and humidity, the equator is actually NOT the hottest place in the world. The temperature in equatorial regions also varies with amount of precipitation and altitude. In fact, a small amount of snow lies on the southern slopes of Volcan Cayambe, a volcano that boasts the highest equatorial altitude, in Ecuador.



Let us know what your favorite season is!