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  • >>Gavin Pretor-Pinney: Ten years ago, it was almost to this week, in fact, I started a

  • society, The Cloud Appreciation Society. And, no, it's nothing to do with the virtual cloud.

  • It's about the real ones up in the sky. It's for people who like clouds, people who dislike

  • blue-sky thinking. And we've got members in 94 countries around

  • the world. They're all united in the belief that we shouldn't just think of clouds as

  • things that get in the way of the sun. We shouldn't just think of them, shouldn't moan

  • about someone having a cloud hanging over them or a cloud on the horizon, because they're

  • what bring variety, beauty, drama to our skies. When was the last time that you sat back and

  • just watched a cloud? Just watched the way it builds in brilliant white, cauliflower

  • mounds? Was it when you were a kid? Before time was money? When your only deadline was

  • bedtime? They're so omnipresent, aren't they, so everyday

  • that it's easy to forget they're even there. It's easy to miss that in a way, clouds are

  • the most dynamic and evocative of nature's displays.

  • So for the next 15 minutes, we're going to forget about blue-sky thinking, and we're

  • going to see what happens when you open your eyes to the formations in this ocean of air

  • above us, when you pay attention to the things that other people miss.

  • So let's start with this cloud here. Does anybody in the audience know what type of

  • cloud this is? Are there any pilots in the audience?

  • It's a cumulus cloud, absolutely right. So this is the fair-weather cloud, forms on a

  • sunny day, borne up on invisible thermals of air rising off the sun-warmed ground. It's

  • the Simpson's cloud, all right? It's the generic one. You close your eyes, think of a cloud,

  • this is the one that comes to mind. And with its crisp, well-defined edges, it's also the

  • best type of cloud for finding shapes in. So it's usually a cumulus that you're looking

  • up at when you glance up and you go, wait a second, it's a goldfish.

  • [ Laughter ] It's usually cumulus there on the other side

  • of the river when you go, it kind of looks like a giant taking a stroll.

  • They're like nature's version of those ink blot images, aren't they? You know, like you

  • say, like shrinks used to show their patients. "What would it mean, Dan, if you look up and

  • you see up above the shopping mall there's the abominable snowman with a gun going to

  • rob a bank? What would that mean?" [ Laughter ]

  • >>> Probably to do with your mother. >>Gavin Pretor-Pinney: Probably to do with

  • your mother. Exactly. Usually is, isn't it? They're the natural stimulants, aren't they?

  • And who here hasn't at one time or another sat back and looked for shapes in the clouds?

  • But perhaps you don't do it so much now that you're adults. Perhaps it feels a bit frivolous

  • to -- a bit aimless, a bit frivolous to look up and go, wait a second, it's an angel with

  • a camcorder. [ Laughter ]

  • Perhaps it's -- feels a bit kind of, well, whatever when you go over and mention to your

  • neighbors that there's an Ostrich pecking on their roof.

  • It may be aimless, but that doesn't mean it's pointless. Because when you have your head

  • in the clouds like this, when your brain is in coasting mode, that's a chance, that's

  • a space for your subconscious to speak. And that's when you give yourself the space to

  • make connections, you know, make novel connections, come up with new ideas.

  • So, those cumulus clouds are nature's invitation to daydream. But those same clouds, under

  • certain circumstances, when the atmosphere is unstable, can build and grow up in the

  • sky. They can grow taller and taller, rising eventually to 8, 10, 12 miles up into the

  • sky. This is when they start to spread out at the

  • top, in enormous anvils covering over hundreds of square miles. It's where it's become the

  • cumulonimbus storm clouds. They're the king of clouds. These majestic beasts of the atmosphere

  • are what produce thunder and lightning and hail, and when they get together, they can

  • combine into enormous and destructive storm systems.

  • The cumulonimbus is the embodiment of the power that drives our atmosphere. And the

  • way it develops out of those innocent little cumulus clouds is an indication of the fact

  • that clouds are forever in flux, forever changing, metamorphosing from one form to another.

  • High clouds, like these Cirrus, are composed entirely of ice crystals. And unlike those

  • low clouds, those cumulus, they're composed of water droplets. So these are ice crystals.

  • And the way these ice crystals form through the sky is what gives this cloud its distinctive

  • wavy streaks. The Latin name for them means a lock of hair.

  • So as those minusculized crystals tumble from the upper reaches of the atmospheres they're

  • swept along in the high winds. 200, 300 miles an hour. And it gives them these very beautiful,

  • I think, wavy appearances. I think it's one of the most beautiful of the common clouds.

  • And these are common clouds. These and the cumulus before and the cumulonimbus are three

  • of the common types of clouds. There are 10 main types. But what about the rarer ones?

  • Because there are many more exotic and unusual forms.

  • For instance, the lenticularus cloud, which looks a little bit like this. There we are.

  • Lenticularus cloud. It's named after the Latin for a lentil. So this forms in stable air

  • in the region of mountains, and as the air rises to pass over the mountain, it can, in

  • certain circumstances, take a rising and dipping path in the lee of the peak with one of these

  • UFO-shaped clouds at the crest of the wave. It's a standing wave of air. So the air and

  • the droplets are all rushing through, but the position of the cloud remains fixed in

  • the sky relative to the mountain. And then there are mamma clouds. So these

  • come from the Latin for udders. And these pouches hang from the underside of the cloud

  • layer. The larger ones, the more dramatic ones form on the underside of the anvil of

  • a storm cloud. The exact mechanism for these clouds to form is still not clear to us.

  • But one of the rarest types of cloud is this one, the Kelvin-Helmholtz wave cloud. It looks

  • like a succession of waves with the tops curling over like ocean breakers. And this is caused

  • by shearing wind, so the wind above the cloud layer and the wind below the cloud layer differ

  • significantly, and in between you get this undulation where the cloud is. And if the

  • difference between those two speeds is just right, then the tops of those undulations

  • curl over in beautiful vortices. Now, all those clouds form within the lower

  • part of our atmosphere. All right? In the part called the troposphere but there's one

  • type of cloud that forms higher than these, much higher and it can only be seen at night.

  • The noctilucent cloud. It's 50 miles up in the atmosphere, so it's not in the stratosphere

  • which is above the troposphere. It's in the mesosphere, the part above that, which is

  • an incredibly cold and incredibly dry part of our atmosphere. And they get the name noctilucent

  • because being so high up, when the sun has gone down over the horizon, the sky has become

  • dark, these still catch the light. Noctilucent means light shining in Latin. They still catch

  • the light and they have these beautiful, eerie, rippled, sort of mysterious appearance to

  • them. Which is kind of appropriate because they are mysterious. We don't understand how

  • the water that forms the ice in these clouds gets up into the incredibly dry part of the

  • atmosphere. Nor do we understand since the end of the 19th century when they were first

  • observed, these clouds seem to be spotted more and more frequently.

  • A few years ago, somebody sent us from the states, in fact, from Iowa, they sent us a

  • photograph of a cloud that looked a little bit like this; all right? Looks like kind

  • of very turbulent sea. Very, very rough turbulent sea, maybe as if you're looking up from below.

  • And when people send them into the Cloud Appreciation Society, we put them up on the gallery and

  • we kind of nerdily decide what type of cloud it is and categorize it, as you do, and I

  • wasn't quite sure what to call these clouds because there is a name for wavy clouds, undulatus,

  • wave clouds, but these seemed like undulatus turned up to 11. They weren't your normal

  • undulatus cloud. Now we then got one -- another one got sent

  • in about a year later. In fact, every once in a while they would appear, and each time

  • I would go there's another one of those sort of weird nameless clouds. Until one day I

  • thought, wait a second. Maybe if they don't have a name, maybe these clouds need a name.

  • Maybe these clouds sent in for our network from all around the world should have a classification

  • of their own. And I thought how do you go about that? Well, you've got to come up with

  • a Latin name, haven't you? And I thought, well, I called up my cousin,

  • Phillip. He's a Latin teacher. And I said, "Phillip, what's a good Latin name could I

  • use for when the sea is rough or turbulent?" And Phillip said, "Glacialis hiemps aquilonibus

  • asperat undas." [ Laughter ]

  • I said it's a bit long. He said no, no, no. That is a term that translates -- that's a

  • quotation by Virgil, the Roman poet, and it means the waves were roughened by the icy

  • winter's northern gales, and the word you want in there is asperat. The verb aspero.

  • It means to be roughened. So asperatus would be the term you'd use for that, roughened.

  • So I thought great. Asperatus. That's what I'm calling it. But how do you go about making

  • a cloud official? Cloud classification official? I know you've all asked yourselves that question

  • at one time or another. [ Laughter ]

  • Well, I took it to the Royal Meteorological Society in the U.K., and I said, "What about

  • this? It's a new cloud type." And they looked at it and said, "Yeah, it's distinctive. You

  • might have a case, but you need to find out more about it."

  • So I took it to the University of Redding, and they said -- they looked into it, looked

  • into the way the cloud formed, stuff like that, and they said, "You may have a case

  • for this being a new classification." But it didn't matter what either of those

  • lots said, because the only people who matter when it comes to the official classification

  • of clouds is the World Meteorological Organization, U.N. organization based in Geneva. They publish

  • the International Cloud Atlas, which is no page turner --

  • [ Laughter ] -- but it is the final word in cloud classification.

  • So if you want your cloud to be official, it's got to get into the International Cloud

  • Atlas. All right? The only problem is -- Well, it's been first published in 1896 and they've

  • had versions every now and then since then. The problem is the U.N. don't do anything

  • in a hurry, as we all know, and they had no plans to do a new edition of the International

  • Cloud Atlas. They'd only just done one in 1974.

  • [ Laughter ] So I wasn't holding my breath. But I was very

  • pleased to hear just last week that perhaps as a result of being hounded by journalists

  • who kind of liked this story, you know, weird guy, wants to name a cloud, viral story handed

  • to them, they decided they are going to do a new edition of the International Cloud Atlas.

  • [ Applause ] They're going to put it -- They got their

  • experts to look into whether there should be any changes or additions to it, and they

  • have concluded that they think asperatus should be a new official classification. The first

  • new cloud type since 1951. [ Cheers and Applause ]

  • People often ask me where in the world is the best place to watch clouds; all right?

  • And one place has to be this, the Salar de Uyuni, which is in Bolivia. Southwest of Bolivia.

  • It's a very large salt flat. 4,000 square miles. You can see, you know, no obstructions

  • to the sky. But the reason this is a good place to watch clouds is because in the wintertime,

  • when it's the wet season, it can get flooded; all right? Heavy rains, and you can get the

  • whole area of the salt flats with one inch of water over it. And this being so still,

  • this water surface acts as a perfect mirror to the sky. So being out on the salt flats

  • is to be suspended in cloud cuckooland. But in fact, it's not the best place to watch

  • clouds because the best place to watch clouds is wherever you are. It's in your backyard.

  • From the window of a plane. When you're on holiday and on vacation, from the beach.

  • And clouds are the most egalitarian of nature's displays. We all have a fantastic view of

  • them. So it doesn't matter. You don't have to go somewhere special to see special clouds.

  • You just have to pay attention to the sky. And that is something that climate scientists

  • have realized we need to be doing more of: Paying attention to the clouds. Because the

  • role that they play in regulating temperatures on Earth is profound, and it's also complex.

  • It's not straightforward. The low clouds, those cumulus I talked about

  • at the beginning, they have the effect of reflecting away more of the sun's heat than

  • they do trap in the Earth's heat. The high clouds, those wispy Cirrus, they

  • don't trap reflect so much of the sun's heat away, but they trap more of the Earth's heat

  • in. So one's cooling and one's warming. And here's the problem. We don't know, as