A winter storm brought heavy rain and snow to parts of the East Coast this weekend, which got us thinking about snowflakes. Those intricate, whimsical crystals are a staple of magical wintry scenes, but how big can they really get? Well, according to the Guinness World Record keepers, the “largest snowflake” ever recorded was a whopping 15 inches in diameter. It was spotted near Missoula, Montana in 1887. But Kenneth Libbrecht, a physicist at Caltech, has long been skeptical of that record. So he set out to find what makes a snowflake a snowflake and whether that 1887 record is scientifically possible. You can read more about what he discovered here.
Want to share the snowflakes you’ve spotted this winter? Email us a photo at shortwave@npr.org.
Listen to Short Wave on Spotify, Apple Podcasts and Google Podcasts.
This episode was produced by Chloee Weiner. It was edited by Rebecca Ramirez and fact checked by Nell Greenfieldboyce. The audio engineer was Valentina Rodriguez.
Transcript:
REGINA BARBER, HOST:
You’re listening to SHORT WAVE…
(SOUNDBITE OF MUSIC)
BARBER: …From NPR.
(SOUNDBITE OF MUSIC)
BARBER: Hey SHORT WAVErs. Winter is here, at least for those of us who live in the Northern Hemisphere of our dear planet. And depending on where you are, there may or may not be snow. The Guinness World Record folks have compiled a bunch of records related to snow, and NPR’s Nell Greenfieldboyce was recently looking at them. Hey, Nell.
NELL GREENFIELDBOYCE, BYLINE: Hey.
BARBER: OK. Hit me with some snow records.
GREENFIELDBOYCE: All right. How about the longest time spent in full-body contact with snow? So that would be 105 minutes and two seconds.
BARBER: Oh, my gosh, those last two seconds must have been, like, intense. OK. Let’s hear another one.
GREENFIELDBOYCE: How about the most people making snow angels simultaneously? So that one is 8,962 people who gathered in North Dakota. And then there’s the largest snowflake.
BARBER: OK.
GREENFIELDBOYCE: So the Guinness people say there was a snowflake 15 inches in diameter and eight inches thick, that fell in Montana in 1887.
BARBER: Wow. OK. So a snowflake that was more than a foot across. Is that, like, even possible?
GREENFIELDBOYCE: OK. That’s what I wanted to know. I mean, come on, that is a big snowflake. And what I learned is that, you know, first of all, you have to make it clear what you mean by the word snowflake. And I recently talked to a couple of scientists about that. One of them is Kenneth Libbrecht. He’s a physicist at Caltech. And that particular Guinness World Record has always kind of bugged him. So he told me that just this past year, like, six months ago, he decided to do something about it.
BARBER: I’m intrigued. OK. Today on the show, we look at snowflakes, how big they can really get and what to think about this 19th-century snowflake that was supposedly as big as a dinner plate. I’m Regina Barber. You’re listening to SHORT WAVE, the science podcast from NPR.
(SOUNDBITE OF REX KALIBUR’S “SNOW FALLS”)
BARBER: OK, Nell. You said you called up a physicist who knows something about snowflakes. What was his name again?
GREENFIELDBOYCE: Kenneth Libbrecht. He really made a name for himself making snowflakes in the lab. Or, as he would point out, he actually makes snow crystals.
KENNETH LIBBRECHT: There’s a little problem with the language in that a snowflake means more than one thing.
GREENFIELDBOYCE: I mean, when I say snowflake, do you imagine something that looks sort of like those snowflakes that people cut out of, like, white, folded pieces of paper with scissors?
BARBER: Yes, absolutely. That six-fold symmetry.
GREENFIELDBOYCE: So that kind of snowflake is really a single ice crystal. But a flake can also mean these big puff balls that fall from the sky that are actually many, many tiny snow crystals that have gotten sort of tangled up together.
BARBER: OK.
GREENFIELDBOYCE: And that’s why the Guinness World Record for the largest snowflake really bothered Kenneth Libbrecht. He says it’s got to refer to that kind of puffball, but…
LIBBRECHT: When people hear the, you know, world’s biggest snowflake, they always imagine a snow crystal, which is a different beast entirely.
GREENFIELDBOYCE: He says, like, there’s no way you would get a natural snow crystal 15 inches across.
BARBER: OK. So how big could that crystal get?
GREENFIELDBOYCE: Well, as I said, you know, he really got famous as someone who could make snow crystals in the lab. And he told me the biggest one he ever made was about an inch across. And he said that one looked pretty crappy. It was kind of falling apart under its own weight. But he also goes out and photographs natural snow crystals like the ones that fall, you know, during a snowstorm. He used to make special trips up to Ontario to this place where the average temperature was about 5 degrees Fahrenheit, which is really optimal for beautiful snow crystals to form.
BARBER: OK.
GREENFIELDBOYCE: And that’s where he was 20 years ago on December 30, watching the snow fall.
LIBBRECHT: Just all of a sudden, these really large flowers just came falling out of the sky. And they were very noticeable ’cause they were just gigantic.
GREENFIELDBOYCE: They were about five times bigger than the average snow crystal, but even so, they weren’t that big. I mean, he got a photo of one that was 10 millimeters across. So 10 millimeters. That’s a centimeter. Or for those of you stuck with inches, it’s like four-tenths of an inch, a little under half an inch.
BARBER: And what he called these flowers were these, like, single crystals, right? I mean, you’re right. That’s not that big, really.
GREENFIELDBOYCE: He says that pretty much all the people who seriously photograph snow crystals – and, like, there aren’t that many of them who are willing to go out with microscopes and cameras and, you know, be out there at night in the cold, you know, watching snowflakes fall – he knows them, and no one has come forward to show him anything bigger than that one. So…
BARBER: OK.
GREENFIELDBOYCE: …About six months ago, he finally, you know, just got sick of this world record for the biggest snowflake that the Guinness World Record people have. And so he contacted them and he told them, look, your big snowflake record from the 19th century is potentially confusing. So why don’t you make a new record for the largest individual snow crystal? And here one is. You know, here it is. I took a photo of it.
LIBBRECHT: And I told them that, you know, even if mine was not the biggest, it may be fun. People might now be inclined to look around and find a bigger one.
GREENFIELDBOYCE: Plus, in their records, they could sort of cross-reference this new world record for the largest snow crystal with their existing record for the largest snowflake, which would, you know, educate people about what these records actually meant. So that’s what they did. They went for it. And the new listing points out that a snowflake is made of many, many individual crystals, and it lists that one he took a picture of as the biggest one.
BARBER: OK. So does that record for the world’s biggest snowflake still stand?
GREENFIELDBOYCE: Yes. It’s still there. But added to it is this extra little qualifier about the largest individual snow crystal.
BARBER: OK. And that takes us back to that original world record – OK? – so that 15-inch snowflake. Even if it was made up of, like, a bunch of these tiny snow crystals, could a snowstorm really make one that big?
GREENFIELDBOYCE: I put that exact question to a researcher who studies naturally falling snowflakes. Her name is Sandra Yuter at the North Carolina State University.
SANDRA YUTER: I must admit, I’m a bit skeptical about it.
GREENFIELDBOYCE: But she wouldn’t flat-out say, like, it could never happen, it’s impossible.
YUTER: This is one of the issues in science is that you can always get outliers.
GREENFIELDBOYCE: Still, OK, think about this. She’s been taking photographs of falling snowflakes for years, and she has never seen one that big. She has this special contraption with motion sensors and cameras and, like, the snow kind of falls through it.
YUTER: One of the interesting things about snow to me is it’s falling just fast enough that we can’t, as humans, see it very well. We sort of get the impression. And so, you know, we’re using this technology to kind of, like, take a snapshot and get a good picture of it.
GREENFIELDBOYCE: And each picture is really cool because it shows just, like, dozens or even hundreds of tiny, tiny snow crystals that are all loosely entangled. So, you know, each individual crystal has its own shape – like you might have needles, like these sort of sharp looking things or little, fuzzy balls – and they’re all sort of very loosely connected into this three-dimensional, complex shape that has this delicate structure. And it’s usually, you know, got a lot of, like, little holes in it and it’s elongated and it’s kind of flattened, you know? So it’s not, like, a round ball or something. It’s really quite weird looking. I mean, I wouldn’t think just looking at snowfall that that is what a snowflake looks like. But when you see it, you know, sort of, like, just white against black, kind of frozen in time, it’s really pretty cool.
BARBER: OK. I want to see these images now, right? But OK, let’s just cut to the chase here. Realistically, what size would she ever expect to see for real, like, out in the wild?
GREENFIELDBOYCE: So she and her colleagues have taken photos of more than 100,000 snowflakes, and the biggest she’s ever seen was 35.33 millimeters across. So that’s like 1.4 inches. Like…
BARBER: Yeah.
GREENFIELDBOYCE: …Almost an inch and a half.
BARBER: Oh. OK. So 1.4 inches is, like, way smaller than that, like, 15-inch record that Guinness is claiming, right?
GREENFIELDBOYCE: Yeah. And they don’t have any photographic evidence for that one, remember. That’s just somebody’s report of what they saw…
BARBER: OK.
GREENFIELDBOYCE: …You know, back in 1887. So, you know, I don’t know. I mean, again, nothing’s impossible, but, you know, the constraints on size have to do with the time that the snow crystals have to kind of glom together before hitting the ground. So, you know, and the amount of snow crystals that are up there, you know, floating around in the storm to potentially collide with each other and get tangled up with each other. So let’s say a storm is six kilometers high, which is pretty typical. A snow crystal might form at the top and then it starts to fall. It starts to drift down, and it’s falling at about a meter per second. So it has more than an hour before it hits the ground, you know, but not, like, infinite time, you know, a couple hours, tops. And as the snow crystal is falling, the wind is blowing it around and it can get tangled up with other crystals that formed, you know, farther down in the storm.
You know, that’s why you have all these different shapes is because the crystals are forming in different conditions in the storm. And so that’s why…
BARBER: Wow.
GREENFIELDBOYCE: …You know, they all look slightly different and they all get mixed up together. And, you know, the flake is falling and it’s growing and it’s growing, but it doesn’t have forever to grow. Eventually it hits the ground.
BARBER: Right. Of course.
GREENFIELDBOYCE: So, you know, to get a snowflake 15 inches, you would need wind and vapor and temperature conditions that would just be really weird. Like, weird enough to generate something, you know, like, more than 10 times bigger than the biggest snowflake Yuter has seen after studying them for years. So, I don’t know. Again, there’s no photographic evidence. Make of it what you will.
BARBER: All right, Nell. I know how I feel about this one. I’m a little skeptical. But thank you for taking us on this tour of the world of large snowflakes. Nell, do you actually like snow?
GREENFIELDBOYCE: I love snow. I love snow, and I love big snowflakes. The bigger and the puffier, the better.
BARBER: Well, then I hope you have many large snowflakes falling around your house sometime soon and a fun day of playing out in the snow.
GREENFIELDBOYCE: Got to love a snow day.
(SOUNDBITE OF VANCE WESTLAKE AND JAMES PETER WILSON’S “MORNING FOCUS”)
BARBER: This episode was produced by Chloee Weiner, edited by our showrunner Rebecca Ramirez and fact-checked by Nell herself. Valentina Rodriguez was the audio engineer. Beth Donovan is our senior director, and Collin Campbell is our senior vice president. I’m Regina Barber. Thanks for listening to SHORT WAVE, the science podcast from NPR.
(SOUNDBITE OF VANCE WESTLAKE AND JAMES PETER WILSON’S “MORNING FOCUS”)
