Understanding the Seasonal Changes
The winter solstice occurs on Saturday, marking the day with the fewest hours of sunlight and the longest night for those in the Northern Hemisphere. This is the perfect time to enjoy holiday lights and snuggle under cozy blankets.
If you prefer more daylight, consider traveling to the Southern Hemisphere, where summer is in full swing. Alternatively, you can simply wait: starting Sunday, the length of daylight will gradually increase in the Northern Hemisphere every day until late June.
For centuries, humans have observed these annual variations in sunlight as the Earth orbits the sun. Ancient structures like Stonehenge in England and the Torreon located at Machu Picchu in Peru were built partly to align with these solstice events.
What Exactly is the Solstice?
The solstices signify key points in the Earth’s orbit around the sun, specifically when the Earth’s axis is tilted at its greatest angle. This tilt leads to unequal distribution of sunlight between the Northern and Southern Hemispheres, resulting in markedly different lengths of day and night.
What is the Equinox?
The equinoxes occur in spring and fall when the Earth’s axis is aligned in such a way that both hemispheres receive equal amounts of sunlight.
The term equinox comes from Latin words meaning “equal” and “night,” indicating that during this time, day and night are nearly of equal length, although minor variations can occur based on your exact location on the planet.
The spring equinox, or vernal equinox, can fall between March 19 and 21, while the fall equinox, also called the autumnal equinox, is observed between September 21 and 24.
Distinguishing Between Meteorological and Astronomical Seasons
There are two primary methods for defining the seasons: meteorological and astronomical. Meteorological seasons are determined by the climate and break the year into four three-month seasons based on average temperature. According to this system, spring begins on March 1, summer on June 1, fall on September 1, and winter on December 1.
Astronomical seasons, on the other hand, are based on the Earth’s position in relation to the sun. The solstices indicate the starts of summer and winter, while the equinoxes mark the beginnings of spring and autumn.
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