Will Spring be early this year?
Yes it will, at least according to the calendar! In the United States, Spring will begin one day early on March 19th! It is the earliest in 124 years!
Last week I saw an American Finch on our bird feeder and I thought that it was really too early for a finch to be so far north. A little later he was joined by a purple finch, but it is another two weeks until the beginning of Spring! A couple of days later a woodchuck was on our back lawn looking for the tasty spring greens. Unfortunately, the snow had just melted away and the grass was still covered with snow in some spots. Nevertheless the woodchuck was out of his burrow and checking things out. My doubts were all blown away when I saw a robin. Robins mean Spring!
When I grew up, the beginning of Spring was always either on the 20th or the 21st of March. In our post of March 2018 we explained the Vernal Equinox and the effect on Spring planting. But this year it is different. Spring will begin on March 19th, 2020. We have to go back 124 years to 1896 to find another Spring beginning on March 19th. In case you thought, as I did, that Spring always begins on March 21, we were only right 36 times in the last 100 years.
Of course there is a reason for why these seasons change. It takes Earth approximately 365.242189 days to go around the sun. The Earth rotates on its axis (the center line around which we spin) at about 23.5 degrees of tilt from the Sun, which gives us our seasons- when the northern hemisphere is tilted away from the Sun our Winters, and on the opposite side of the orbit our Summers, when the northern hemisphere is tilted toward the Sun. But our orbit is not a perfect circle, but rather an ellipse (more like an oval)- which takes us further and then closer to the sun at various times. Ever since humans have tried to measure the passage of annual seasons, these variables have confounded accuracy.
Of course there is a reason for why these seasons change. It takes Earth approximately 365.242189 days to go around the sun. The Earth rotates on its axis (the center line around which we spin) at about 23.5 degrees of tilt from the Sun, which gives us our seasons- when the northern hemisphere is tilted away from the Sun our Winters, and on the opposite side of the orbit our Summers, when the northern hemisphere is tilted toward the Sun. But our orbit is not a perfect circle, but rather an ellipse (more like an oval)- which takes us further and then closer to the sun at various times. Ever since humans have tried to measure the passage of annual seasons, these variables have confounded accuracy.
Why has an accurate calendar been so important to us? Well, our reliance on animal migrations for food and the blossoming of plants to eat, certainly compelled us to predict the seasons to avoid starvation. When we adopted agriculture and lived in one place, it was perhaps even more important! Our crops could be planted too late or too early, resulting in famine.
There have been many calendars designed by people over history, with varying successes. The Romans had the ‘Roman Calendar’- which consisted of 12 months, with occasional recalculations of added days to keep it synced. These additions were proscribed by pontificates (high priests) and were frequently dictated by politics. Also, the vast Roman empire encompassed many different cultures and locally influenced calendars. Administering a vast bureaucratic empire, involving taxation and military deployments, with widely disparate calendar events, must have been a nightmare! They didn’t have ‘icloud calendar syncing’ back in those days, so I imagine we would have been adrift back then.
So by edict of Julius Caesar, the Julian Calendar was adopted on January 1, 709. It was pegged to the movement of the Sun, in order to avoid human intervention. Perhaps this was one of the earliest attempts to keep politics out of what we now call science! There have been many other calendars developed since then.
We have chosen the Gregorian Calendar to keep dates and times as accurately (unfortunately not really) as possible. Pope Gregory XIII promulgated this new calendar in 1582. It was more accurate than the Julian calendar. It was adopted by Great Britain on 9/2/1752 (not so long ago), in order to better match up with European countries and by default became the American colonies’ calendar. This change necessitated advancing the calendar by 11 days. So after Wednesday September 2, 1752, the next morning became Thursday September 14, 1752! How confusing was that to trade bookkeepers? The oceanic world trade for the British was at a zenith at this point. Was this their equivalent of Y2K- self-imposed? Did their bookkeeping suffer? (Just curious after thought).
But this calendar was also afflicted with the best assumption, at the time, that each year’s journey around the sun, was actually 365.25 days long. Today, our modern astrophysicists have been able to calculate that it is actually approximately 365.242189 days to go around the sun! So this tiny rounding error has complicated consequences. Of course ¼ of a day will add up in a few years. Therefore we have to add a whole day in a leap year, but not every four years. If you cannot divide the year evenly by 400 (like 2100) it does not get the extra day. And there is another rule: If the year ends in “00” it also must be divisible by 400 to allow for a February 29th to be added.
And of course the Earth’s orbit around the sun is elliptical. As the seasons follow a precise 90 degree angle to the sun, the Earth sometimes needs a little more time to reach this point. (Please bear with me here.) Now it really gets complicated and it is a kind of a numbers game.
In order for Earth to reach the 90 degree mark in the northern hemisphere, it needs in
Winter: 88.99 days
Spring: 92.76 days
Summer: 93.65 days
Autumn: 89.84 days.
As you see, the warmer season is 7.573 days longer than the colder season.
And of course the Earth’s orbit around the sun is elliptical. As the seasons follow a precise 90 degree angle to the sun, the Earth sometimes needs a little more time to reach this point. (Please bear with me here.) Now it really gets complicated and it is a kind of a numbers game.
In order for Earth to reach the 90 degree mark in the northern hemisphere, it needs in
Winter: 88.99 days
Spring: 92.76 days
Summer: 93.65 days
Autumn: 89.84 days.
As you see, the warmer season is 7.573 days longer than the colder season.
Astronomers are not done yet. Spring will get shorter for one minute per year for the foreseeable future, and Winter one-half minute per year. Summer will get the Spring minute and Autumn the half minute from Winter. Winter’s projected minimum value, i.e. 88.71 days, will be reached in the year 3500. And of course, one has to factor in the effects of the Earth’s precession (how the Earth’s axis wobbles like a slowing top along its annual journey around the Sun) and the variable effects that this has on seasons in different hemispheres.
Whew! I’m glad I’m not a rocket scientist! How did we manage to coax a camera into orbit around planets millions of miles away and years later, to thrill us with extraterrestrial landscapes? We should be in awe of our scientists! The first Moon landing was accomplished with less computing power than a smartphone!
In order to make March 19th, 2020, the beginning of Spring, we had to add 5 hours and 49 minutes to our calendar to align 2020 with 2019. Instead of adding only 5 hours and 49 minutes, a whole day was added! Therefore, for the next few years, Spring will begin on March 20 or 21, until the added 5 hours and 49 minutes are used up.
Whew! I’m glad I’m not a rocket scientist! How did we manage to coax a camera into orbit around planets millions of miles away and years later, to thrill us with extraterrestrial landscapes? We should be in awe of our scientists! The first Moon landing was accomplished with less computing power than a smartphone!
In order to make March 19th, 2020, the beginning of Spring, we had to add 5 hours and 49 minutes to our calendar to align 2020 with 2019. Instead of adding only 5 hours and 49 minutes, a whole day was added! Therefore, for the next few years, Spring will begin on March 20 or 21, until the added 5 hours and 49 minutes are used up.
So our calendars are still imperfect, and we will continue to make clumsy adjustments, until our technology melds with our social and economic models for ultimate precision. Until then, Earth will slightly tilt towards the sun and our days will get longer and get more sunshine. And that is the signal for nature to start growing its plants, grass and the trees will get the leaves. It is a new beginning. Spring will arrive no matter the calendar.
In our post of March 2018 we described the impact the beginning of Spring has in other cultures.
Keep in mind that in the Northeast of the United States, snow storms can surprise you well into April. The legendary blizzard of 1888 took place in the middle of March (see our post of February 2017), but after the beginning of Spring, the tilt of the Earth helps us to get over snow faster. The days are longer and the sun is stronger, melting the snow away.
In our post of March 2018 we described the impact the beginning of Spring has in other cultures.
Keep in mind that in the Northeast of the United States, snow storms can surprise you well into April. The legendary blizzard of 1888 took place in the middle of March (see our post of February 2017), but after the beginning of Spring, the tilt of the Earth helps us to get over snow faster. The days are longer and the sun is stronger, melting the snow away.
Confused by all the math? You don’t need to be. Just remember, if you are in an area of the globe where annual time changes are observed, Spring forward one hour with your clocks, and Fall back one hour, and you’ll be fine.
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