How much do you know about the spring equinox? WLTX Meteorologist Alex Calamia drops some weather facts about the season.
See this experiment, as well as several others, in action thanks to our friends at WLTX.
Did You Know...
The official first day of spring, the spring equinox, has nothing to do with weather. It’s when day and night are considered equal.
In 2020, it’s happening on March 19th, which is the earliest it has ever happened in our lifetime. That’s why March 19th might sound like an unusual day to have that first day of spring. Because it’s been more than a 100 years since it has happened.
You might think this has to do with the weather - which it doesn’t. You might also think it has to do with astronomy - which it kind of does. However, it also has to do with how we track time in the first place.
How long is a year really? It's a much more complicated question than you might think. The amount of time it takes for the Earth to orbit around the sun is approximately 365 days, five hours, 59 minutes and 16 seconds. That’s according to NASA, but it changes a little bit each and every year. It’s never perfectly the same. It’s always different by a couple of seconds or a couple of minutes. So, that alone is a complication. It’s also not exactly six hours. That’s why just adding a leap year and adding that extra day every four years during the leap year doesn’t solve the problem.
From this point forward, here's an analogy to make things a little more simple. Designate a white car for the true year and a burgundy car for the calendar year. The goal is for both cars to be in sync or neck-and-neck. However, it's never going to happen because the true year changes ever so slightly, and the calendar year is only using increments of a day, so it’s impossible to really get them to line up. When the calendar year is 365 days, that isn’t good because it is going to very quickly fall behind. It’s too slow. So, the leap year solution really does help. Unfortunately, adding that extra day every four years eventually makes the calendar year go too fast.
Here's a rule that a lot of people don’t know, but every 100 years, the leap year is skipped. For example, 1896 was a leap year, 1900 wasn’t a leap year and 1904 was a leap year. It really helps things get closer in sync, but eventually, the calendar year still falls behind.
So, another rule comes into play. Every 400 years that rule of skipping a leap year to start a century is actually ignored. Eventually, the calendar year kind of ends up going a little faster, but they are much more neck-and-neck.
Let's take a look at what happened in 2000. We actually had a leap year. 2000 was one of those once-in-a-400-year events where you celebrate a leap year at the start of the millennium. What it did was make spring come a little earlier and earlier every leap year since. So, the 2000 leap year started on March 20th at 2:35 a.m., and ever so slightly, the first day of spring has been creeping a little earlier and earlier to now - the year 2020 -where for the first time in the eastern half of the country, the spring equinox celebration is March 19th.
By the way, every single leap year from this point forward - up to year 2100 - is going to be the earliest first day of spring that has ever been seen.
A reminder, the changes have no impact on our weather, but they are definitely kind of interesting - a good conversation starter.
Alex Calamia is a morning meteorologist at WLTX in Columbia, SC. You can watch his forecasts every weekday. Learn more about Calamia and how he got interested in weather by clicking here.