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The 2020 vernal equinox will bring the earliest spring to the US in 124 years

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Come Thursday (March 19), we will have a change of the seasons: the occurrence of the vernal equinox, marking the official start of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. In fact, it will be a rather auspicious occurrence: the earliest that the equinox has occurred nationwide in 124 years. More on that in a moment.

The exact moment of the equinox will occur Thursday night at 11:49 p.m. EDT (0349 GMT on March 20), according to the astronomy reference book “Astronomical Table of the Sun, Moon and Planets” (Willmann-Bell, 2016). At that time, the Earth will reach the point in its orbit where its axis isn’t tilted toward or away from the sun. Thus, the sun will then be directly over a specific point on the Earth’s equator moving northward. On the sky, it’s where the ecliptic and celestial equator cross each other.

This image of Earth was captured during the spring equinox in 2011 by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on the Meteosat-9 satellite. (Image credit: NASA)

A not-so-equal equinox

On the day of the equinox, the sun will appear to rise exactly east and set exactly west. Daytime and nighttime are often said to be equally long with the equinox, but this is a common misconception — the day can be up to 8 minutes longer, depending on your latitude.

The sun is above the horizon half the day and below for half — but that statement neglects the effect of the Earth’s atmosphere, which bends the rays of sunlight (called refraction) around the Earth’s curvature when the sun lies close to the horizon. But, because of this bending of the sun’s rays, the disk of the sun is always seen slightly higher above the horizon than it really is.

In fact, when you see the sun appearing to sit on the horizon, what you are looking at is an optical illusion; the sun at that moment is actually below the horizon. So, we get several extra minutes of daylight at the start of the day and several extra minutes more at the end.

The supposed equality of day and night gives us the Latin name “equinox,” which means “equal night.” But in reality, thanks to our atmosphere, the day is longer than the night at the equinox. At the latitude of New York, for instance, day and night are roughly equal a few days before the equinox, on St. Patrick’s Day (March 17).

Sun overhead from the Emerald of the Equator

Astronomers can calculate the moment of the vernal equinox right down to the nearest second. This year it will occur on Thursday (March 19) at 11:49:28 p.m. EDT (0349 GMT on March 20). At that moment, the sun will appear directly overhead about 50 miles (80 kilometers) south of Gorontalo, a province of Indonesia — often referred to as the “Emerald of the Equator” — on the island of Sulawesi, on the equator in the Gulf of Tomini. In the days that follow, the direct rays of the sun migrate to the north of the equator and the length of daylight in the Northern Hemisphere will correspondingly appear to increase.

Why so early?

As was noted, this will be the earliest that the vernal equinox will occur across the contiguous United States in 124 years. There are two specific reasons for this variation of the date: leap years and daylight saving time.

When a leap year set us back a day

First, that 2020 is a leap year (meaning that the month of February had one extra day) is not the reason for the early arrival of this year’s equinox. Rather, it is the leap year that we observed in the year 2000.

Let’s look at the dates and times of the vernal equinoxes leading up to 2000. Note that each year the occurrence of the equinox happens about 6 hours (or one-quarter of a day) later in the calendar:

  • 1996: March 20 at 3:03 a.m. EST (0803 GMT)
  • 1997: March 20 at 8:54 a.m. EST (1354 GMT)
  • 1998: March 20 at 2:54 p.m. EST (1954 GMT)
  • 1999: March 20 at 8:46 p.m. EST (0146 GMT on March 21)
  • 2000: March 20 at 2:35 a.m. EST* (0735 GMT)

In 46 B.C., Julius Caesar’s consulting astronomer, Sosigenes, knew from Egyptian experience that the solar year was about 365.25 days in length. So to account for that residual quarter of a day, an extra day — leap day — was added to the calendar every four years. Unfortunately, the new Julian calendar was 11 minutes and 14 seconds longer than the actual solar year. By the year 1582 — thanks to the overcompensation of observing too many leap years — the calendar had fallen out of step with the solar year by 10 days.

It was then that Pope Gregory XIII stepped in and, with the advice of his own astronomer, Christopher Clavius (1538-1612), produced our current “Gregorian” calendar. First, to catch things up, 10 days were omitted after Oct. 4, 1582, making the next day Oct. 15. In order to better adjust the new calendar format to more closely match the length of the solar year, most century years (such as 1700, 1800, 1900) — which in the old Julian calendar would have been observed as leap years — were not. The exceptions were those century years equally divisible by 400. That’s why 1700, 1800 and 1900 were not leap years.

But 2000 was a century year, evenly divisible by 400, so it was observed as a leap year. Had we skipped the leap year in 2000 (as in 1900), then the vernal equinox in 2000 would have occurred a day later, on March 21 at 2:35 a.m. EST (0735 GMT).

Hence, the reason we have an asterisk next to that date.

So, thanks to February having an extra day in 2000, the date of the equinox slipped back a day to March 20.

Daylight saving time delayed the equinox in the East

Because the solar year is not exactly one-quarter of a day longer than the 365-day calendar year, but a little bit less than one-quarter (24.22%) of a day, the occurrence of the equinox comes about 47 minutes earlier (on average) every four years:

  • 2000: March 20 at 2:35 a.m. EST (0735 GMT)
  • 2004: March 20 at 1:48 a.m. EST (0648 GMT)
  • 2008: March 20 at 1:48 a.m. EDT (0548 GMT)*
  • 2012: March 20 at 1:14 a.m. EDT (0514 GMT)
  • 2016: March 20 at 12:30 a.m. EDT (0430 GMT)
  • 2020: March 19 at 11:49 p.m. EDT (0349 GMT on March 20)

The asterisk (*) indicates that the United States and Canada had begun observing daylight saving time on the second Sunday in March rather than the first Sunday in April, a practice that began in 2007. In 2000, only those in the Pacific time zone (as well as in Alaska and Hawaii) observed the equinox on March 19. In 2004, 2008 and 2012, those time zones again saw spring arrive on March 19, along with people on Mountain Time.

In 2016, those in the Central time zone celebrated a March 19 arrival. Were we still on the old system (when daylight saving time did not begin until early April), we would have been on standard time in 2016, and those in the eastern parts of North America, too, would have observed the equinox on March 19 (at 11:30 p.m. EST), but daylight time pushed that off for another four years. Finally this year, from coast-to-coast, spring will arrive on March 19 — the earliest in 124 years.

And as a point of record: In 1896, the vernal equinox arrived on March 19 at 9:29 p.m. EST (0229 GMT on March 20).

Astronomical vs. meteorological spring

Truth be told, there are really two springs: astronomical spring and meteorological spring.

Astronomical spring is measured by the vernal equinox, but that’s only a marker in the big flow of time, set up by astronomers — a sidereal milepost, accurate as a ticking clock but only approximately timing the changing of the seasons.

Meteorological spring supposedly has already started as of March 1, and runs through the end of May, according to Accuweather. In truth, however, meteorological spring ignores the clock and calendar, makes its own rules and creates a festival of song and blossom, all in its own time.

The crocuses, early robins and other vernal phenomena pay no attention to the hairsplitting details marking the astronomical arrival of the vernal equinox. They all have their own way of knowing when spring truly begins.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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