Mark Strehl Blog: Spring arrives
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SPRING! The change of seasons from one to another occurred Friday, March 20th. And to be precise, it happened at 5:45 pm central time.
That was the exact moment that the Sun's vertical rays crossed the equator. That means that our days continue to lengthen, and in the Southern Hemisphere the days will become shorter. This happens because the Earth is tilted on its axis, and because of that tilt, different regions of the earth receive differing amounts of sunshine throughout the year.
Our days become longer right up to June 21st when we hit the Summer Solstice, the "longest Day" of the year. Then the process reverses itself right through next December when we start the cycle all over again!