The Seasons
for the classroom, home schoolers, and theme decor for offices.

Seasons are the periodic divisions of the year experienced as changes of weather. Because the Earth has a 23.5° axis tilt to the orbit plane, the northern and southern hemispheres alternate in distance from the sun. This difference in exposure is enough to make a major change in daylight hours and conditions for plant growth.

Equinoxes and solstices mark relative positions of the orbiting Earth to the sun. Equinox is related to the word equal and means the sun is observed directly above the equator and experienced as 12 hours of sunlight and 12 hours of darkness. Equinoxes occur twice a year - around March 20 and September 23, and observed as the first days of Spring and Autumn respectively, in the Northern Hemisphere. Solstice (sol + stitium= stoppage), is when the sun is furthest from the celestial equator and experienced as either the shortest (Winter) or longest (Summer) day of the year, depending on hemisphere. Stonehenge is an example of an ancient astronomical observatory, where the people could predict be assured that the sun was following its usual path.

Weather posters

The “tropics”, the region circling the planet Earth at the equator and limited by the the lines of latitude called the Tropic of Cancer (23°27'N) and the Tropic of Capricorn (23°27'S), experience the seasons as dry or rainy. The temperate zones, global climate bands that lie between the tropic latitudes and the polar circles (66˚33' 38"N/S), experience gradual extremes. Seasons around the North and South Poles are noted annually by at least one 24 hour period of constant daylight or darkness. <geography posters>

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