Home > Encyclopedia of Science > Seasons

• Reason for the seasons
• Words to Know
• The equinox
• The solstice
• Celebrating the seasons

Seasons on Earth are characterized by differences in temperature and the length of daylight. The four distinct seasons—spring, summer, autumn (or fall), and winter—are found only in the temperate zones. These zones extend from 23.5 degrees North (and South) latitude to 66.5 degrees North (and South) latitude. The equatorial regions or torrid zones have no noticeable seasonal changes, only a wet season and a dry season. Polar regions experience only a light season and a dark season.

Spring comes from an Old English word meaning "to rise." Summer originated as a Sanskrit word meaning "half year" or "season." Autumn comes originally from a Etruscan word for...