DENVER (CBS4) – This week marks the spring (vernal) equinox which is the beginning of the spring season for the northern hemisphere. In school you may recall learning that spring arrives on or around March 21 each year.
This year spring will arrive on March 19 for all time zones in the United States. It will be the earliest arrival of spring since 1896 according to The Old Farmer’s Almanac.
So why? It’s a complicated answer but the simple reason is that it has to do with time and subtle shifts in our calendar.
Specifically it’s about if the turn of a century involved a leap year or not. The year 2000 was a leap year and now we are seeing a consequence of that. Astronomer Bob Berman with The Old Farmer’s Almanac explains in his blog that our calendar experiences a little tweak every 400 years when the turn of the century contains a leap day.
Bob says we will see more and more “earliest springs on record” over the next few years before spring once again starts arriving on the 21 of March in the year 2103. Be sure to click the link above and read his blog because I think you will find it very interesting and educational.