Sunday, March 15, 2020

Spring Equinox 2020: The Earliest First Day of Spring in 124 Years| Farmer's Almanac

When Is The First Day of Spring in 2020?

The first day of spring will occur on Thursday, March 19, 2020, at 11:50 p.m. EDT for those of us in the Northern Hemisphere, which is marked by the arrival of the Vernal (Spring) Equinox.

If this seems early to you, you’re right! In fact, this is the earliest the Vernal (Spring) Equinox has occurred in 124 years.

Traditionally, we celebrate the first day of spring on March 21, but astronomers and calendar manufacturers alike now say that the spring season starts on March 20th, in all time zones in North America. And in 2020, it’s even a day earlier than that—something that hasn’t happened since 1896.

Regardless of what the weather is doing outside, the equinox marks the official start of the spring season.

How could the first day of spring change from year to year?

There are a few reasons why seasonal dates can vary from year to year. The first is that a year is not an even number of days and neither are the seasons.

Another reason is that the earth’s elliptical orbit is changing its orientation (skew), which causes the earth’s axis to constantly point in a different direction, called precession.

Since the seasons are defined as beginning at strict 90-degree intervals, these positional changes affect the time the earth reaches each 90-degree location in its orbit around the sun.

The pull of gravity from the other planets also affects the location of the earth in its orbit. The current seasonal lengths for the Northern Hemisphere are:

Summer — 93.641 days
Autumn — 89.834 days
Winter — 88.994 days
Spring — 92.771 days

As you can see, the warm seasons, spring and summer, combined are 7.584 days longer than the colder seasons, fall and winter (good news for warm weather admirers).

However, spring is currently being reduced by approximately one minute per year and winter by about one-half a minute per year. Summer is gaining the minute lost from spring, and autumn is gaining the half a minute lost from winter.

Winter is the shortest astronomical season, and with its seasonal duration continuing to decrease, it is expected to attain its minimum value — 88.71 days — by about the year 3500.

Length of Day Vs. Night

Another complication revolving around the vernal equinox concerns the length of day versus night. We have been taught that on the first days of spring and autumn, the day and night are equal to exactly 12 hours all over the world.

Yet, if you check the calendar pages in our Almanac, you will find that this is not so. In fact, our tables tell you that on the days of the spring and fall equinox, the length of daylight is actually longer than darkness by several minutes.

The reason this happens can be attributed to our atmosphere. If the earth was a planet that did not have an atmosphere, then yes, on the equinox days the length of the day and night would be exactly even.

However, our atmosphere acts like a lens and refracts (bends) its light above the edge of the horizon. Put in another way, when you watch the Sun either coming up above the horizon at sunrise, or going down below the horizon at sunset, you are looking at an illusion — the Sun is not really there, but already below the horizon.

As a result, we actually end up seeing the Sun for a few minutes before its disc actually rises and for a few minutes after it has actually set. Thus, thanks to atmospheric refraction, the length of daylight on any given day is increased by approximately six or seven minutes.

What Does Vernal Equinox Mean?

Vernal translates to “new” and “fresh,” and equinox derived from the Latin aequus (equal) and nox (night).

So what does that mean? Essentially, our hours of daylight — the period of time each day between sunrise and sunset — have been growing slightly longer each day since the Winter Solstice in December, which is the shortest day of the year (at least in terms of light).

Even after three months of lengthening days, though, we still see less light than darkness over the course of a day. The vernal equinox marks the turning point when daylight begins to win out over darkness.

At this moment, the direct rays of the Sun are shining down on the equator producing the effect of equal day and night (give or take a few minutes). After the vernal equinox, the direct rays of the Sun migrate north of the Equator (with hours of daylight steadily growing longer) until they finally arrive at the Tropic of the Cancer (latitude 23.5 degrees north).

The migration of the Sun’s direct rays comes to a halt on that day; this is as far north as they will go. We call this the summer solstice (solstice is a suspension of the migration of the Sun’s direct rays). It is the longest day of the year in terms of hours of daylight.

After the summer solstice, the direct rays proceed to head south and the days begin to grow shorter. It will take another three months, until the autumnal equinox for the periods of daylight and darkness to reach equilibrium once again.

The rays ultimately reach the Tropic of Capricorn (latitude 23.5 degrees south) on the day of the winter solstice and the whole cycle begins again!

Seasons
https://youtu.be/tX3Y5bzNDiU

https://youtu.be/tX3Y5bzNDiU

What’s in store for spring? Be sure to check our spring forecast here.

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https://www.farmersalmanac.com/spring-equinox-first-day-spring

Friday, March 20, 2015

First Day of Spring 2015: Vernal Equinox | Farmer's Almanac

Well, technically Spring beings at 6:45pm EDT, so Friday is the last DAY of WINTER here in the Northeast, and we have snow ushering in the Equinox in the late afternoon, but by Saturday, it will be above freezing again. Once I see Crocuses and purple Squill (the ground is still covered with snow at the moment) then it will really feel like Spring has arrived. -PB
First Day of Spring 2015: Vernal Equinox
| Farmer's Almanac

When does spring 2015 begin? On this page, get informed about the vernal equinox, spring weather—and a solar eclipse!

Astronomically speaking, the March equinox occurs when the Sun crosses the celestial equator on its way north along the ecliptic. In the Northern Hemisphere, the March equinox is known as the vernal, or spring, equinox, and marks the start of the spring season.

In the Southern Hemisphere, this equinox is known as the autumnal, or fall, equinox and marks the start of the fall season; the vernal equinox for the Southern Hemisphere occurs in September.
The March equinox happens at the same moment across the world but is converted to local time. In 2015, it falls on March 20 at 6:45 P.M. EDT, 5:45 P.M. CDT, 4:45 P.M. MDT, and 3:45 P.M. PDT, for example.

Meteorologically speaking, however, in the Northern Hemisphere the official spring season always begins on March 1 and continues through May 31. Summer begins on June 1; autumn, September 1; and winter, December 1.

Weather scientists divide the year into quarters this way to make it easier to compare seasonal and monthly statistics from one year to the next. The meteorological seasons are based on annual temperature cycles rather than on the position of Earth in relation to the Sun, and they more closely follow the Gregorian calendar. Using the dates of the astronomical equinoxes and solstices for the seasons would present a statistical problem because these dates can vary slightly each year.

Spring 2015 Weather Forecast

Ah, spring! Ready for some warmer temperatures?! See the Almanac's spring 2015 forecast summary.

The Vernal Equinox

The word equinox is derived from the Latin words meaning “equal night.” All over the world, days and nights are approximately equal. Today, the Sun rises exactly in the east and sets exactly in the west.

At the equinoxes, the tilt of Earth relative to the Sun is zero, which means that Earth’s axis neither points toward nor away from the Sun. (However, the tilt of Earth relative to its plane of orbit, called the ecliptic plane, is always about 23.5 degrees.)

Enjoy the increasing daylight! See how your day "grows" with our personalized Sun rise and set calculator.

A Total Solar Eclipse

This year there is a total eclipse

of the Sun on the day of the Vernal Equinox! This is quite rare; the next time this happens is 2034. The total solar eclipse occurs over the Faroe Islands, off Scotland; the path of totality then marches directly to—and stops at—the North Pole. See our 2015 eclipse page.
In addition, on March 20, we have a second celestial event: a Supermoon! In our Sky, the Moon, which was at perigee less than 24 hours prior, turns into a "New Moon" on the 20th. It is not visible; however, it has a larger-than-average effect on Earth’s oceans. See our Moon phase calendar.

Equinox Facts

Question: Why doesn’t the vernal equinox (equal night) on March 20 have the same number of hours for day and night?

Answer: Our former astronomer, George Greenstein, had this to say: "There are two reasons. First, light rays from the Sun are bent by the Earth's atmosphere. (This is why the Sun appears squashed when it sets.) They are bent in such a way that we are actually able to see the Sun before it rises and after it sets. The second reason is that daytime begins the moment any part of the Sun is over the horizon, and it is not over until the last part of the Sun has set. If the Sun were to shrink to a starlike point and we lived in a world without air, the spring and fall equinoxes would truly have ‘equal nights.’”

View the reason for the seasons and why the seasons change.

Equinox Folklore

Question: According to folklore, you can stand a raw egg on its end on the equinox. Is this true?

Answer: One spring, a few minutes before the vernal equinox, several Almanac editors tried this trick. For a full workday, 17 out of 24 eggs stood standing. Three days later, we tried this trick again and found similar results. Perhaps 3 days after the equinox was still too near. Try this yourself and let us know what happens!

Spring Verse

One swallow does not make a spring.
Bluebirds are a sign of spring; warm weather and gentle south breezes they bring.
In spring, no one thinks of the snow that fell last year.
Don’t say that spring has come until you can put your foot on nine daisies.
Spring-time sweet!
The whole Earth smiles, thy coming to greet.

Signs of Spring

The vernal equinox signals the beginning of nature’s renewal in the Northern Hemisphere. Worms begin to emerge from the earth, ladybugs land on screen doors, green buds appear, birds chirp, and flowers begin to bloom.

You can track when the seasons change by observing (and recording) the plants and animals around you.

How do you know that spring is coming? Share your comment below!

Seasons of 2015:

SPRING EQUINOX: March 20, 6:45 P.M. EDT
SUMMER SOLSTICE: June 21, 12:38 P.M. EDT
FALL EQUINOX: September 23, 4:21 A.M. EDT
WINTER SOLSTICE: December 21, 11:48 P.M. EST