Speaker 1: Attention, Chicago and Toronto. We're coming to see you guys soon,
Speaker 1: so we better hurry up and buy your tickets because
Speaker 1: they're going fast. Yeah, man, Chicago at the Hairs Theater July.
Speaker 1: We've actually sold a lot of tickets now, yeah, you
Speaker 1: guys listen, thank you, thanks for stepping up. In Toronto
Speaker 1: at the Danforth Music Hall the next night, July. It
Speaker 1: may be sold out by now. Yeah. Well, there's only
Speaker 1: one way to find out. Go on to s y
Speaker 1: s K live dot com and you'll find links to
Speaker 1: the ticket sites and all the show info you need,
Speaker 1: and we will see you soon. Welcome to Stuff You
Speaker 1: Should Know, a production of I Heart Radios How Stuff Works. Hey,
Speaker 1: and welcome to the podcast. I'm Josh Clark, and there's
Speaker 1: Charles w Chuck Bryant, there's Jerry over there, and this
Speaker 1: is Earth Science Time. Baby. I love this stuff. Yeah,
Speaker 1: this one was a little well, it's about dry. I
Speaker 1: just caught myself at the last second. Thank you. It
Speaker 1: was a little dry though, Uh it was, But I
Speaker 1: mean we're talking sand dudes. There's just so much you
Speaker 1: can do with something, do you know what I mean? Yeah,
Speaker 1: But it's also one of those is kind of neat,
Speaker 1: and that when next time I go to the beach
Speaker 1: or the desert, I will I'm armed with a little
Speaker 1: more knowledge, which is always nice. Are you gonna go
Speaker 1: do some sandboarding? I don't think so, although I did
Speaker 1: look at some videos. It sounds pretty awesome to me.
Speaker 1: It looks like a great way for a forty eight
Speaker 1: year old to break his knee. Did you, oh man,
Speaker 1: breaking your knee? Can you imagine? No? Did you, um
Speaker 1: listen to the sound of dunes singing? Uh? Yeah, and
Speaker 1: I've heard that sound like in person? What kind of
Speaker 1: life have you lived? I mean a life wire been
Speaker 1: around some sand dunes? Wow, that's neat. I think I
Speaker 1: heard the dune singing on a TV commercial shoot out
Speaker 1: in the desert. That's where I heard it. Well, what
Speaker 1: were they singing? Do you remember they were singing? Uh?
Speaker 1: Fresh friends? No, No, these were not European dunes. So
Speaker 1: you've been, um nice, you've been around dunes that were
Speaker 1: not beach dunes, because my only experience has been just
Speaker 1: beach dunes. Standards, stay off the dunes, beach dunes. These
Speaker 1: are desert dunes. That's pretty neat. Yeah, it looked like
Speaker 1: in fact, I believe they had even done some Star
Speaker 1: Wars reshoots in this area of California. Wow, it wasn't Tunisia,
Speaker 1: but it stood in for Tunisia. So I was told,
Speaker 1: just like those hills stood in for Korea and mash
Speaker 1: that's right. But this is a Michael bay Chevy commercial, okay.
Speaker 1: And I got to stand around and watch him scream
Speaker 1: at everybody that's neat man, what a good guy? Um Like,
Speaker 1: I said, I've only been around dunes on the beach,
Speaker 1: coastal dunes, right, coastal dunes. But I was talking to
Speaker 1: you me, and I guess these would constitute coastal dunes.
Speaker 1: But she said she taught in Japan, you know, um
Speaker 1: years and years ago, and a prefecture called to Tori,
Speaker 1: which is the least populated prefecture in Japan, and they
Speaker 1: actually had some amazingly beautiful dunes which look like desert dunes,
Speaker 1: but it's coastal. So I guess they're coastal dunes. But
Speaker 1: they don't look like coastal dunes. They look like desert
Speaker 1: dunes in South Carolina. No, it's definitely not. And I
Speaker 1: was like dunes in Japan that doesn't make any sense.
Speaker 1: But I saw him with my own eyes. And unless
Speaker 1: she photoshopped these pictures they were real, which would have
Speaker 1: really been something because they weren't even her pictures. They
Speaker 1: were posted on the internet. It would be a weird thing.
Speaker 1: I suppose she could have photoshop the pictures, started a
Speaker 1: website with an unrelated name uploaded um and then made
Speaker 1: it look like she was searching just Google images, which
Speaker 1: she was just to fool me. And then she's like,
Speaker 1: I got you on a dune fake burn right, classic
Speaker 1: dune fake fake but she um. She also, by the way,
Speaker 1: she when she taught in Japan, um, she taught with
Speaker 1: our buddy Raymie, who we're going to see in Toronto soon.
Speaker 1: That's great. Which, by the way, if you haven't gotten
Speaker 1: your tickets to Chicago, it's probably too late for Toronto
Speaker 1: by the time this comes out. How about this. If
Speaker 1: you're listening to this and you haven't bought your ticket
Speaker 1: for Portland's Maine, shame on you. Okay, So sand dunes.
Speaker 1: I love this article, by the way by Debbie Ronka yep,
Speaker 1: And she basically says a sand dune needs three things
Speaker 1: to form. You need loose sand because that's the kind
Speaker 1: that can blow around you need wind to blow a
Speaker 1: sand dune around, and then you need an obstacle, which
Speaker 1: can be anything. It can be a bed of pebbles,
Speaker 1: it can be a big rock, can be a tree,
Speaker 1: but it's something for the sand to hit and say, oh,
Speaker 1: I can't go any further. And then as more and
Speaker 1: more sand hits that obstacle, the sand dune starts to build,
Speaker 1: and then the sand dune itself becomes the obstacle. In
Speaker 1: one of the most zen processes around on Earth. It
Speaker 1: really really is. It's a true like uh layering effect
Speaker 1: that if you see sped up with the time lapse camera, yeah,
Speaker 1: it's pretty remarkable. Well, that actually reveals maybe the fact
Speaker 1: of the podcast to me, sand dunes move. I thought
Speaker 1: you're gonna say time lapse photography is possible, right if
Speaker 1: but if you watch the sand dune over a long
Speaker 1: enough exposure, you would see it moving forward. And here's
Speaker 1: the thing. It doesn't just move in that like the
Speaker 1: sand gets blown around and and you know, the sand
Speaker 1: dune takes all these different shapes. It keeps its shape
Speaker 1: and just moves forward depending on the type of dune
Speaker 1: and the type of what's called wind regime in the area.
Speaker 1: That's right. I just think that it is amazing. They're
Speaker 1: clearly alive and can feel pain. So you really shouldn't
Speaker 1: walk on the sand, dude. And the shape is so
Speaker 1: dictated by the fact that, you know, maybe the wind
Speaker 1: always blows in one direction where you are maybe opposed
Speaker 1: in two directions only maybe it blows from many directions,
Speaker 1: and that's all gonna dictate this malleable living, breathing, breathing, feeling,
Speaker 1: emotional beast right, that will kill you if you don't
Speaker 1: treat it right. It has. It's killed a couple of
Speaker 1: people at least. So let's talk about how wind can
Speaker 1: move sand around. Uh. It's generally a few different ways.
Speaker 1: There's uh saltation, which is mostly like of sand. Grains
Speaker 1: move like this and that's just the wind is just
Speaker 1: bouncing them along. Yeah, I thought these percentages were pretty specific.
Speaker 1: Four percent, one percent, Like who who came up with
Speaker 1: those percentages? Okay, all right, well then they probably are accurate.
Speaker 1: There's creep, Yes, creep I'd never witnessed or heard of before,
Speaker 1: of you, I don't think. So that's the four percent
Speaker 1: um of sand moves this way, and this is when
Speaker 1: grains are colliding with other grains um, like you know,
Speaker 1: maybe gravel or something causing them to move. It's like
Speaker 1: sand croquet. Yeah. Um, salmon croquettes, No, those aren't the
Speaker 1: best croquettes if you ask me. Frankly, I'm just gonna
Speaker 1: come out and say it. The only way to eat
Speaker 1: salmon is raw. I'm sorry. Oh I love a grilled
Speaker 1: salmon with that crispy skin. M m mmm. I like
Speaker 1: grilled fish. It's just when salmon is cooked, it undergoes
Speaker 1: a taste conversion that I'm not a fan of. I
Speaker 1: prefer it raw. No, I love raw salmon for sure,
Speaker 1: but I love that crispy skin so much. Hey, i'm
Speaker 1: not yucking your young man. If you like cooked salmon,
Speaker 1: have at it. And I do like fish skin, crispy
Speaker 1: fish skin. I'm with you, but I'm more like a
Speaker 1: cooked trout fish skin kind of guy. Yeah. Uh. When
Speaker 1: I was a kid, a very big seventies meal um
Speaker 1: in my household was the canned salmon croquettes. Oh yeah,
Speaker 1: I've had those. Yeah, it's just the bones, you know,
Speaker 1: Like I don't like there to be bones in my food.
Speaker 1: I'm with you. I'll eat something off the bone. I
Speaker 1: just don't want to be expected to actually eat the bone.
Speaker 1: I guess I don't know at a good butcher or
Speaker 1: a good fisher. Okay, but don't that. But aren't there
Speaker 1: still really really tiny little bones. It depends on the salmon.
Speaker 1: But sure with you. I don't like bones either, so um.
Speaker 1: Obviously we're talking about sand dunes still. Yeah, but the
Speaker 1: suspension is the third way. We gotta finish that up
Speaker 1: right right, Um, that's where that's where the wind blows
Speaker 1: very strongly, um, so strongly and from enough different directions
Speaker 1: at once that it actually lifts the sand into the air.
Speaker 1: And this is what a US storm is, or a
Speaker 1: sandstorm or um any number of Basically, if they're sand
Speaker 1: blowing around in the air, that's this is the suspension
Speaker 1: movement of sand up though in the air. Like when
Speaker 1: you go to the beach. Sometimes you'll see sand in
Speaker 1: the right conditions blowing along the ground that couple inches
Speaker 1: off the ground. That's not the same thing, man, No,
Speaker 1: that's saltation. That hurts. That's really painful. Yeah, I guess
Speaker 1: it can hurt, can it? Oh? It can hurts. So um,
Speaker 1: we've kind of already described like how a sand dune forms, um,
Speaker 1: sort of sort of, but the there's there's a lot
Speaker 1: of different kinds of sand dunes. We're gonna get into it,
Speaker 1: don't worry. But there's a general way that a sand
Speaker 1: dune forms where the sand blows along hits a something
Speaker 1: that stops. It's for momentum, and then it starts to
Speaker 1: pile up. And when this piling up happens, a sand
Speaker 1: dune typically undergoes a fairly predictable um evolution, I guess,
Speaker 1: whereas more and more sand builds up, the sand dune
Speaker 1: gets bigger and bigger, and the sand just kind of
Speaker 1: smacks into the back of the sand dune, and the
Speaker 1: lighter sand will just continue up and over the sand dune.
Speaker 1: And then once it makes it down the other side,
Speaker 1: which is called the slip face, which is the side
Speaker 1: that's protected from the wind, the um the sand dune
Speaker 1: just kind of gets bigger and bigger. But eventually enough
Speaker 1: sand will pile up on the back side that it
Speaker 1: forms a crest where it basically piles up and forms
Speaker 1: a peak or crest or something like that. And then
Speaker 1: this crest can get so so big and so pronounced
Speaker 1: that it will actually crumble under its own weight. Yeah,
Speaker 1: I mean, it's just it's like raw physics before your
Speaker 1: very eyes. These layers, those light sands blowing over and
Speaker 1: it's layer after layer building up. Then that crest gets
Speaker 1: super tall, like you could mess around with it if
Speaker 1: you had a big bucket of dry sand with your
Speaker 1: own hand. Sort of see this effect as you drop sand. Eventually,
Speaker 1: when it does collapse, it's gonna avalanche down the slip
Speaker 1: face and there is an angle it's called the angle
Speaker 1: of repose, where it's sort of where that beautiful, Um,
Speaker 1: what's the word I'm looking for. Not symbiosis, but when
Speaker 1: when something's pushing against something, the other things pushing right back,
Speaker 1: and it all agrees that just to stop there in
Speaker 1: the middle. I don't remember what it's called, but I
Speaker 1: know what you're talking about. It is beautiful, that's basically it.
Speaker 1: It's about thirty to forty thirty four degrees in general,
Speaker 1: and that's when it just reaches that perfect angle of
Speaker 1: steepness that it's all just stable and solid. Right, So
Speaker 1: now you have a dune. It's no longer being born.
Speaker 1: It's now living, and it's it's it still can keep growing,
Speaker 1: but it's going to keep growing along these lines where
Speaker 1: you know, if if enough gets built up, it's gonna
Speaker 1: fall down into the angle of repose. More likely, the
Speaker 1: sand will just continue going over the edge and then
Speaker 1: being built up on the back side too. It's a
Speaker 1: rump will grow basically. Yeah. And if you're like, winds
Speaker 1: are really strong, it's probably gonna be taller. If the
Speaker 1: winds are really gentle, it's probably going to be more
Speaker 1: spread out. And the direction of the wind, the angle
Speaker 1: of the wind um and like we mentioned earlier, whether
Speaker 1: or not its unidirectional, bi direction or multidirectional, that's all
Speaker 1: gonna play a part into what kind of dune you're
Speaker 1: gonna get. So let's take a break and then we'll
Speaker 1: come back and talk about the different kinds of dunes. Okay,
Speaker 1: all right, Chuck. Have you ever read the book Dune? Nope?
Speaker 1: I haven't either. Have you ever seen the movie? Nope?
Speaker 1: Me either. That's interesting. You know they're making they're making
Speaker 1: it again. Uh, that's great. That Dennis villaenieu guy. So
Speaker 1: oh he's good. Yeah, he's amazing. He did the arrival, right,
Speaker 1: I think so? Yeah? Or just a arrival. The arrival
Speaker 1: is like old Charlie Sheen movie. I think, I think
Speaker 1: it's just a arrival. Okay, yeah, so, um, neither one
Speaker 1: of us has seen or red dune. We're gonna get
Speaker 1: some email about this, I think. Yeah. And I'm not
Speaker 1: knocking David Lynch either, of course, I want to throw
Speaker 1: that in there, or Frank Herbert. Yeah, I'm just kidding.
Speaker 1: I don't know anything. So um. So, like you were saying,
Speaker 1: dunes are the result of the winds that are im
Speaker 1: prevalent in the area, and the most common dune on
Speaker 1: Earth and um, little known fact, well maybe not little known,
Speaker 1: but interesting fact. Um, the most common dunes on Mars
Speaker 1: or what it called a cynic or crescent shaped dunes
Speaker 1: and these are far and away the most common. Um,
Speaker 1: which means that more often than not, in any given area,
Speaker 1: the wind is going to be blowing in the same
Speaker 1: direction basically all the time. Yeah. And this got a
Speaker 1: little confusing for me because the more I researched the
Speaker 1: types of dunes, like I saw one place it said
Speaker 1: there are five main types of sand dunes Barkin, transverse, blowout, linear,
Speaker 1: and composite. Who said that a website that seemed very
Speaker 1: educational and reliable. Weird, But I believe they are just
Speaker 1: different words for some of these, and some of these
Speaker 1: are subtypes of the main five. Because I believe a
Speaker 1: crescentic is a bark in dune. Yes, if I'm not mistaken,
Speaker 1: you're not horseshoe shaped front facing the wind, I guess. So. Yeah,
Speaker 1: that's the big thing is where is the curve pointing
Speaker 1: is the big differentiator for chryscentic. Yeah, Like I look
Speaker 1: these up online, all these pictures, and like when I
Speaker 1: saw the chriscentic, uh, these look like sort of those
Speaker 1: big beautiful dunes from Star Wars or Lawrence of Arabia. Yeah,
Speaker 1: it's what most people think of when they think of
Speaker 1: a dune. It's like a desert dune, right, exactly, thank you.
Speaker 1: So chryscentic is if you imagine it is like a
Speaker 1: U shape or a V shape. The underside or the
Speaker 1: bottom of the U or the point the outside point
Speaker 1: of the V is going to be pointing in the
Speaker 1: direction opposite the wind, so it's pointing up wind. So
Speaker 1: the wind is blowing and hitting that outside point of
Speaker 1: the V or the bottom of the U, which doesn't
Speaker 1: really make sense um to me. The parabolic, which we'll
Speaker 1: talk about later, makes more sense. But anyway, the parabolic
Speaker 1: the same as a blowout, because a blowout dune is
Speaker 1: the opposite of a bar can, and that the curve,
Speaker 1: the horseshoe curve, faces away from the wind. Yes, okay,
Speaker 1: it's gonna take five minutes to undo the confusion we
Speaker 1: just created. Well, and there are some who studies this,
Speaker 1: what kind of geologists I believe, desert ecologists. Yeah, I'm
Speaker 1: sure they are having a ball with this one. Just
Speaker 1: up a drink, everybody, Yeah, all seventeen of them, buckle up.
Speaker 1: So crescent shaped ones again, say they're U shape or
Speaker 1: V shaped, and the bottom of the U or the
Speaker 1: point of the V is pointing facing the wind, so
Speaker 1: pointing up wind, the wind blows it. The wind the
Speaker 1: sand that it's blowing onto the backside, onto the rump
Speaker 1: of this dune blows up, it falls down avalanches, uh
Speaker 1: under the slip face which is the inside of the
Speaker 1: U or the V, and it's not as protected from
Speaker 1: the wind. And what's amazing about this is because the
Speaker 1: crescent shaped dune is the result of a wind regime
Speaker 1: where the wind is blowing in one direction basically all
Speaker 1: the time. These are the dunes that can actually move
Speaker 1: and they can move pretty fast. They're one of two kinds,
Speaker 1: but they can move pretty fast across the desert, so
Speaker 1: much so that sometimes these dunes, when there's many of them,
Speaker 1: will catch up to one another, and they'll do some
Speaker 1: pretty amazing things when they catch up to one another. Yeah,
Speaker 1: and so much so that they can threaten uh like villages,
Speaker 1: and people have to try and stop these dunes. Yes,
Speaker 1: some people have been known to pour motor oil on
Speaker 1: dunes to keep them from moving. Because it winds the
Speaker 1: sand without it drying out. It's not a good one. Um.
Speaker 1: You could plant vegetation, although if you're in the desert,
Speaker 1: that's not a great great thing because your plants are
Speaker 1: just gonna die. Um more often than not. If you
Speaker 1: just put up fencing, that that becomes an obstacle for
Speaker 1: the dune, and the dune will stop in its tracks
Speaker 1: and it will just keep building up on the back side.
Speaker 1: Eventually it might be big enough to overcome the dune,
Speaker 1: but it will certainly slow it down for a good
Speaker 1: many years for sure. But the thing about that crescent shape,
Speaker 1: when when a small one catches up to a bigger one,
Speaker 1: a lot of things can happen. One thing is that
Speaker 1: it can appear as if the small one passes straight
Speaker 1: through the big one. It is amazing. And then another
Speaker 1: thing that can happen is to to um dunes. I
Speaker 1: don't remember how if they're the same size or different
Speaker 1: size when they come together, so that the arms are
Speaker 1: the wings of the horns of that crescent shape, right,
Speaker 1: not the main part, but the points that come out.
Speaker 1: Those are called the horns of actually seen arms too.
Speaker 1: There's all sorts of different names. It's a giant mess.
Speaker 1: Nobody can agree on anything with dune ecology. But when
Speaker 1: a different dune catches up and merges with it, it
Speaker 1: can actually go from two dunes to three, which is
Speaker 1: called breeding and the two So there's the one dune
Speaker 1: that remains and then the other one basically splits into
Speaker 1: two dunes that come out. The arms are the points
Speaker 1: of the original dune. So when you had two, now
Speaker 1: there's three, which is pretty astounding if you ask me,
Speaker 1: because we're talking sand dunes here and breeding new dunes. Amazing.
Speaker 1: I think it's pretty amazing too. So among the five types,
Speaker 1: there's also enlisted as a transverse dune. I didn't understand
Speaker 1: them at all. Well, I think these are the ones
Speaker 1: that their long lines of rigid dunes and they're perpendicular
Speaker 1: to the wind. Uh. They have really steep slip faces
Speaker 1: at the backsides, and they're kind of wavy. So there's
Speaker 1: a lot of sand and not a lot of plants.
Speaker 1: And I think the dunes that like you see um,
Speaker 1: like behind the beach are a lot of times are
Speaker 1: transverse dunes. Okay, if I'm not mistaken, my understanding was
Speaker 1: that parabolic we're the most um coastal dunes, maybe not
Speaker 1: the most coastal, right, and I think there are different
Speaker 1: kinds of dunes even along the coast, right, Yeah, yeah,
Speaker 1: for sure. Again, it just depends on what the wind
Speaker 1: is like in an area. And because wind regime is
Speaker 1: going to be different for every kind of area, there's
Speaker 1: different kinds of dunes. And um, what we're talking about
Speaker 1: are the standard simple kinds of dunes. Dunes can like
Speaker 1: we like we were just saying, can merge with one another.
Speaker 1: Winds can change and different types of dunes will start
Speaker 1: to form. You've got um compound and complex dunes to
Speaker 1: which can be two different kinds of dunes merged together. Um.
Speaker 1: So there's a lot of weird things that can happen
Speaker 1: with dunes. They're they're very rarely just a simple, straight up,
Speaker 1: straightforward kind of dune. Yeah, there are linear dunes. Uh.
Speaker 1: These are mostly parallel to the wind, and these form
Speaker 1: these long straight ridges and they think geologists think that
Speaker 1: they are caused by wind that blows in one They
Speaker 1: are definitely bi directional as far as the wind goes,
Speaker 1: but they think they're cause when wind blows from one
Speaker 1: direction in one part of the year and then another
Speaker 1: direction and another part of the year, right, So they're
Speaker 1: they're like long lines basically. Yeah. But it's interesting that
Speaker 1: you know, the winds will shift over you know, like
Speaker 1: the course of a year, so it's not like every
Speaker 1: day they're shifting, no, but it's enough and they're powerful
Speaker 1: enough that they're blowing any any kind of um rump
Speaker 1: or base of these and it's just a big long
Speaker 1: line of saying sometimes very sharp depending on you know,
Speaker 1: just how sharp the bi directionality of the wind is.
Speaker 1: Um star ones. This is one of my favorites. These
Speaker 1: are pretty cool. So if you tell what you would think, Yeah,
Speaker 1: if it's like a sand dune that looks a bit
Speaker 1: like a star, they have a pyramidal mound that goes
Speaker 1: up in the middle um and then at least three
Speaker 1: arms with um slip faces, you know, the avalanche face
Speaker 1: radiating out from that middle And these are the results
Speaker 1: of a bunch of different wind directions throughout a year
Speaker 1: building up. So rather than moving along the face of
Speaker 1: the earth, these things is kind of build up in space.
Speaker 1: And they're actually some of the tallest ones. I think
Speaker 1: there's some that are like fivet tall in deserts in China, um,
Speaker 1: which is pretty pretty amazing. I mean that's tall, especially
Speaker 1: if you're a sand border. Yeah, I mean you can
Speaker 1: simulate all this stuff, like you can make your hand
Speaker 1: the wind if you're at the beach and you're playing
Speaker 1: with sand. I mean you just think about if you're
Speaker 1: pushing the sand in one direction only, it's gonna look
Speaker 1: a certain way. If you push then in another direction,
Speaker 1: that's gonna look a certain way. And then in the
Speaker 1: case of a star, if you're using your hand pushing
Speaker 1: sand in and all these different directions, it's gonna grow
Speaker 1: upward and it's not gonna grow laterally. Right right. We
Speaker 1: should have probably said at the outset that it helps
Speaker 1: a lot if you go look up images of the
Speaker 1: different types of dunes we're talking about. Help me and
Speaker 1: look up. Look up dune porn. Yeah, I'm sure it's
Speaker 1: out there. Um okay, Now there's parabolic or parabolic I say.
Speaker 1: You say parabolic, I say parabolic. So these are basically
Speaker 1: the opposite of crescent shaped, where this time, the inside
Speaker 1: of the U or the inside point of the V
Speaker 1: is what the wind is blowing into, and then the
Speaker 1: outside of the U or the outside of the V
Speaker 1: is what's facing in the direction that the wind is going.
Speaker 1: But it's down wind, right. It's what you would think of,
Speaker 1: like if you're just thinking about moving sand with wind
Speaker 1: via physics. This this one makes the most sense. But
Speaker 1: the thing about parabolic that really distinguishes it from crescent
Speaker 1: is that usually they're made of sand that is, has
Speaker 1: some sort of water attached to it or vegetation so
Speaker 1: that the arms are anchored, So the arms stay in
Speaker 1: the same place. They just get longer and longer as
Speaker 1: the bulk of the dune the middle part keeps moving
Speaker 1: further and further away, which is pretty cool if you
Speaker 1: especially if you imagine this stuff on a like a
Speaker 1: time lapse or you know, happening really quickly. Yeah, I mean,
Speaker 1: it can be a little treaty shrubs, grasses and what
Speaker 1: we'll talk more about what can grow in dunes. But
Speaker 1: these things very much served as the anchor on those arms. Uh.
Speaker 1: And these are not gonna be very tall obviously if
Speaker 1: you think about like the way they're going to form,
Speaker 1: the fact that those arms are anchored down, they're not
Speaker 1: gonna be super tall. Um. And then where that vegetation
Speaker 1: is gonna stop, it's gonna slow the advance of that
Speaker 1: sand accumulation. Right. They used to think it was strictly
Speaker 1: just the vegetation um that anchors the arms, but they
Speaker 1: apparently have discovered recently that no, it's actually more water
Speaker 1: logged sand like in the arms than than we previously thought.
Speaker 1: And it's probably the water it acts as motor oil,
Speaker 1: that's right. And then on this original nost of five
Speaker 1: main types, the composite dunes were the last one listed,
Speaker 1: and this is just sort of a combination of two
Speaker 1: or more types of other dunes. Um, these are really big,
Speaker 1: they're very tall. Uh. They form these big hilly forms
Speaker 1: called draws d r a a s and they're mostly
Speaker 1: transverse in linear dunes, and they can be like taller
Speaker 1: than fours. They're they're gigantic. Wow, that's really cool. What
Speaker 1: makes them so big? I think just the combination of
Speaker 1: the dunes I was just just running together. That's pretty neat. Um.
Speaker 1: There's another one I want to give a shout out
Speaker 1: to Chuck is lithified dunes or slick rock, like the
Speaker 1: kind of that you see like in a painted desert
Speaker 1: or whatever. That's actually like a hardened sand dune that
Speaker 1: over time water has flown, has moved through, and as
Speaker 1: it moved through, it basically fossilized the sand dune because
Speaker 1: it deposited minerals of different types. And these minerals can
Speaker 1: create like layers or strata um that that have different colors.
Speaker 1: And that's but it's actually originally it was a sand dune. Gorgeous.
Speaker 1: I've been you talk quite a few times, yep. Uh.
Speaker 1: And we to talk about the subaqueous too, because those
Speaker 1: are pretty great. They're underwater dunes and uh, if you've like,
Speaker 1: you see these a lot in natural channels like rivers
Speaker 1: and stuff. Um, but they can also form and you
Speaker 1: know in a canal that man has built, which is
Speaker 1: pretty interesting. They moved downstream always and they tend to
Speaker 1: be of the same height and the same wavelength the
Speaker 1: same frequency, like they're they're equally spaced apart. And I
Speaker 1: didn't realize this, but it makes total sense. The presence
Speaker 1: of um dunes on the bottom of like a channel
Speaker 1: or a river or something. It increases the river's likelihood
Speaker 1: of flooding because it decreases um flow. It increases resistance,
Speaker 1: decreases flow, and so the water actually piles up and
Speaker 1: overflows because it's running into sand dunes at the bottom. Amazing,
Speaker 1: It is amazing. I don't know if we've gotten this
Speaker 1: across yet or not everybody, but sand dunes are a
Speaker 1: little more amazing than you might have thought, certainly more
Speaker 1: amazing than say, Jackhammers. You want to take another break, Yeah,
Speaker 1: let's do it. We're going to take a break everybody,
Speaker 1: in case you didn't here, and we will be right
Speaker 1: back with coastal dunes. Okay, So the dunes that I
Speaker 1: am probably most people have seen more than any our
Speaker 1: coastal dunes, the dunes at the beach, the dunes that
Speaker 1: have a science says stay off the dunes. There's probably
Speaker 1: some plants growing on them, and UM didn't protected. They
Speaker 1: are protected and they're protective too, that's right, But really
Speaker 1: I was I realized this as I was researching this
Speaker 1: tuck they really protect human interests. They don't really do.
Speaker 1: They don't. There's not a whole lot that they're doing
Speaker 1: besides replenishing the sand that makes up the shore ecosystem
Speaker 1: after a storm. They're basically like a reserve sand um pile,
Speaker 1: so that when a storm happens that the sea goes,
Speaker 1: give me some of that, and it takes the sand
Speaker 1: out and replenishes it and then starts this process over again.
Speaker 1: Because that's where the sand dune originally comes from. Is
Speaker 1: waves bring sand ashore, and the sand starts to blow
Speaker 1: inward inland and runs into something in the way, And
Speaker 1: like I said, at the outset, it could be a
Speaker 1: bed of pebbles, it could be shells, it could be
Speaker 1: some vegetation that's already growing there, and it starts to
Speaker 1: build up. And that's where coastal sand dunes begin. Yeah,
Speaker 1: it's really cool they have. First of all, uh, an
Speaker 1: embryo done is a real term, which is really kind
Speaker 1: of funny and kind of like I imagined, is like
Speaker 1: sticky in Yoki Cross. But how how these things uh like,
Speaker 1: how vegetation comes to um to work with dunes, and
Speaker 1: they kind of scratch each other's backs. Uh. In this
Speaker 1: case is rotting seaweed will will come in from a storm,
Speaker 1: let's say, because a sand dune in itself originally doesn't
Speaker 1: have like a ton of nutrients to allow stuff to grow. Yeah,
Speaker 1: it's just minerals basically, like like quarts and ground up
Speaker 1: calcium carbonate and not much else. Yeah, so you would
Speaker 1: be surprised if anything grew there. But what will happen
Speaker 1: is the tide will bring in plant life and like
Speaker 1: rotting seaweed and added, you know, they dump their nutrients
Speaker 1: there and that allows what they call a pioneer species
Speaker 1: to colonize because all of a sudden there's some nutrients there.
Speaker 1: And this can be mainly grasses, like all different kinds
Speaker 1: of kinds of sea grasses and uh, these plants, you know,
Speaker 1: these are sea grasses. So they you know, they can
Speaker 1: grow well in really harsh conditions like super salty area
Speaker 1: as um they're getting beat by wind and they really
Speaker 1: typically have these big, deep, long roots. They're gonna go
Speaker 1: all the way down to the water table and that's
Speaker 1: we're gonna they're gonna get there, uh their drink, and
Speaker 1: they're gonna just bind that sand together. And it's like
Speaker 1: I said, they kind of work together to make the
Speaker 1: sand makes the plant stronger. The plants make the sand
Speaker 1: stronger or the dune rather yeah. Yeah, And once those
Speaker 1: pioneer species of grasses are established, they start to change
Speaker 1: the actual like composition of the dune and they make
Speaker 1: it more um. Yeah to other kinds of species that
Speaker 1: aren't quite as pioneering but are still pretty hardy compared
Speaker 1: to say like you're you know, your your rosebush or something.
Speaker 1: They there's you know, woody perennials like um beach elder.
Speaker 1: There's heaths and heathers UM in the UK, they grow
Speaker 1: on on coastal dunes and UM. All that these do
Speaker 1: is create uh an eve and stronger, more nutrient rich
Speaker 1: type soil as these things live and grow and fix
Speaker 1: nitrogen and turn more seaweed into even more nutrients UM.
Speaker 1: And they also allow it to retain water. Although I
Speaker 1: think basically to a species, any plant that can grow
Speaker 1: on a sand dune is is basically developed UM techniques
Speaker 1: to resist losing water. Like they have small crinkly leaves
Speaker 1: that that don't evaporate water nearly as easily. So the
Speaker 1: name of the game is to get as many nutrients
Speaker 1: out of unfriendly um soil as possible and keep as
Speaker 1: much of the water as you can get from the
Speaker 1: water table. Yeah, which is why they protect dunes. I mean,
Speaker 1: when you when you go to the beach, you're gonna
Speaker 1: see signs that say stay off the dunes, and you
Speaker 1: don't want to, you know, because the fear is that
Speaker 1: humans will go in there, which is exactly what would happen,
Speaker 1: and trample on these grasses. And then that little relationship
Speaker 1: is busted apart when those grasses die off or even worse,
Speaker 1: are pulled up, maybe because you want to take some
Speaker 1: home or something, and then the sand dune is compromised.
Speaker 1: Look at the girl from the beach, so one one.
Speaker 1: Even without human intervention, these coastal dunes can turn into
Speaker 1: parabolic dunes if something happens, like a storm search happens
Speaker 1: and carves out like a significant portion of the sand
Speaker 1: in front of the dune, because now there's nothing holding
Speaker 1: that dune in place, and it's exposed to the wind
Speaker 1: even further, and so the dune itself will start to
Speaker 1: move forward, but the arms will stay in place, and
Speaker 1: that's the coastal dune is just turned into a parabolic
Speaker 1: dune too, and it's moving inland, which if you have
Speaker 1: a house built there, that's a problem for you. But
Speaker 1: one thing that I didn't realize, but I totally now
Speaker 1: I've I've seen it all over the place, but I
Speaker 1: never put tune two together. If you've ever noticed, um,
Speaker 1: an established beach will almost always have like a conifer
Speaker 1: like pine tree forest. And apparently that's like the end result,
Speaker 1: like of the progressional evolution of a don ecosystem, is
Speaker 1: a pine forest is going to grow because they're adapted
Speaker 1: to grow in this this soil that's been prepared over
Speaker 1: time that started out as a single piece of dead
Speaker 1: seaweed and ended up into a whole pine forest. I mean,
Speaker 1: for sure, there are a lot of pine trees in
Speaker 1: the Florida Panhandle. Yeah, but you never think about it.
Speaker 1: But that's that that's like a don eco system. But
Speaker 1: that's part of the dune. That's like the I think
Speaker 1: the climax ecosystem is what they call it. Yeah, And
Speaker 1: I don't know if you've ever been to a beach
Speaker 1: not so long after a hurricane is hit, but it, uh,
Speaker 1: it's just devastating to look at. I mean, you always
Speaker 1: obviously think of people in homes that are destroyed and
Speaker 1: stuff like that, but if you look at the actual
Speaker 1: beach itself, um, it's pretty brutal. Like it can take
Speaker 1: decades for that beach itself to recover and for those
Speaker 1: dunes to re cover. Um. Like I was in South
Speaker 1: Carolina not a couple of years ago, not too long
Speaker 1: after one of the hurricanes, and it was like you're
Speaker 1: used to seeing these big broad beaches with these big
Speaker 1: flowy dunes, and this was like a cliff. It was
Speaker 1: just sand that eventually went up. Uh, you know, the
Speaker 1: water line met just a hard like jeez a man,
Speaker 1: some places like ten and twelve feet like a sand cliff,
Speaker 1: and it just looks completely unnatural, like not like the
Speaker 1: beaches that you're used to seeing. And selfishly, as you
Speaker 1: know as a beach goer, some parts were just completely impassable,
Speaker 1: Like you couldn't even get to the beach unless you
Speaker 1: like repelled down the wall or something, and you certainly
Speaker 1: couldn't get back up from what I could tell, though,
Speaker 1: that's just part of this natural process. And like removing
Speaker 1: and then slowly replenishing, and like I was saying earlier,
Speaker 1: the dunes protect human habitation. Like you want a dune
Speaker 1: if you live on a coastal beach area. It's like
Speaker 1: a big stack of sandbags. It is, and and like
Speaker 1: you build your house right behind it, and it provides
Speaker 1: this buffer from storm surges and stuff like that. But
Speaker 1: when it's when it's taken away, if it takes decades
Speaker 1: to rebuild, you may want to move elsewhere. Apparently after
Speaker 1: Hurricane Sandy, there's parts of New Jersey still that they're saying, like,
Speaker 1: I don't know if this is habitable anymore. Maybe it
Speaker 1: will be in like fifty years after the dunes come back.
Speaker 1: But this is not like it's it's like we can't
Speaker 1: live here anymore. It's because the dunes have have been removed.
Speaker 1: And people in New Jersey said, have you ever been
Speaker 1: to Newark? Yeah? At the New York's come a long way,
Speaker 1: has it? Oh? Sure, okay? But when I first started
Speaker 1: going there in the in the early to mid nineties,
Speaker 1: it was it was a different story. I love Newark,
Speaker 1: it's great. Do you really sure? Okay? I love all
Speaker 1: of New Jersey. That's my second home, all right, there
Speaker 1: you go. Speaking of second homes, we should talk about that.
Speaker 1: What little critters make their home their first time them
Speaker 1: in the dunes? M hm do you like? Well? I did?
Speaker 1: It was pretty nice. That was a classic sk So
Speaker 1: I mean kind of like we were talking about before,
Speaker 1: like a big pile of sand is not an an
Speaker 1: intuitive place for plants to live or animals to live. Um,
Speaker 1: but because of all the nutrient dumps that the ocean
Speaker 1: brings in, uh, it can, uh it can end up
Speaker 1: being a really thriving ecosystem. There can be little little
Speaker 1: flower dune flowers. There can be little rats and mice. Uh,
Speaker 1: certainly snakes and lizards if you're in the desert. Um.
Speaker 1: But obviously these are only going to be things like
Speaker 1: you can't completely discount like nature. These all have to
Speaker 1: be very very drought tolerant. Plants Oh yeah, for sure,
Speaker 1: but there are adapted to grow on these dunes. And
Speaker 1: you know when you add a plant and a lizard
Speaker 1: and an insect and a bird or something like that, Um,
Speaker 1: you got yourself a nice little ecosystem going. And they're
Speaker 1: definitely dune ecosystems that have developed over time. Beatles, crickets, Yeah,
Speaker 1: I was looking up. I was like, our dung beetles
Speaker 1: a dune bug. Apparently, my friend, dung beetles are an
Speaker 1: anywhere beetle there on every continent, in just about every
Speaker 1: ecosystem except for Antarctica. Really, yeah, we're gonna have to
Speaker 1: do at least the short stuff on the dung beetle
Speaker 1: because it's a poop beetle. It gathers poop, and I
Speaker 1: think that's pretty neat. Yeah. I remember watching those guys
Speaker 1: roll those little poop balls around and the what was
Speaker 1: it the Planet Earth videos? Yeah, for sure, pretty great,
Speaker 1: or maybe it was micro Cosmos. I can't remember it was.
Speaker 1: They they're I mean, they're they're pretty frequent TV gets
Speaker 1: in a lot of movies. Remember when they're on the
Speaker 1: Man Drill Sister Show. Yeah, man, that was brought the
Speaker 1: House down, Man Drill Sisters. Did you watch that? No?
Speaker 1: I grew up in Ohio. We didn't have that. Oh
Speaker 1: it was nation wide, you kidd me? No, I'm I'm
Speaker 1: sure this is when people in New York City watched
Speaker 1: he haw Right. Yeah, I know. Everybody was on cebes
Speaker 1: and acted like they were truckers, wore truckers shirts. Crazy.
Speaker 1: That was a cool little period in the seventies, you know. Yeah,
Speaker 1: it was a little weird trucker culture took over yeph
Speaker 1: What else is gonna hurt dunes? Deforestation? It sounds weird
Speaker 1: to use that word about um sand dunes, but yeah,
Speaker 1: I mean there's those coda for forests. Yeah, you can
Speaker 1: DeForest e conifer forest just like any other forest. You jerk,
Speaker 1: not you, I'm saying the person who cuts down the
Speaker 1: conifer forest. That's right. Yeah, what else you got anything else? Uh? Now,
Speaker 1: we talked about the singing sand dunes, which if you
Speaker 1: haven't heard, go listen. It's pretty neat and it's really
Speaker 1: just sand, dry sand falling over itself in an avalanche,
Speaker 1: and again proof positive that sand dunes are alive and
Speaker 1: can feel pain. That's right. Uh, that's it for sand dunes.
Speaker 1: I think the last thing we have to say is
Speaker 1: stay off the dunes. If it says day off the dunes,
Speaker 1: just don't go on them, especially with your dune buggy.
Speaker 1: Yeah that was that was another seventies little fad to
Speaker 1: doom buggies. Yeah. They they also have beaches still where
Speaker 1: you can drive your car. I'm not a big fan
Speaker 1: of that. No, because even if it's not eroding the beach.
Speaker 1: It's small gone the beach. Come on, it's just ugly.
Speaker 1: You don't want to go to the beach and see
Speaker 1: someone's stupid car. Nope, I can barely stand seeing people's
Speaker 1: bare feet. Agreed. Uh, Well, since we said that, it's
Speaker 1: time of course, friends for listener mail. Uh. Chuck got
Speaker 1: me out of a parking ticket. Hi, guys, my name
Speaker 1: is Camber M a grad student at Indiana University, Go Hoosiers. Uh.
Speaker 1: But I work in Indianapolis, A fairly new listener about
Speaker 1: six months. But I have to drive a lot for
Speaker 1: school and work and family, so I spent a lot
Speaker 1: of time listening to you guys. Uh. And I need
Speaker 1: to let Chuck know that he saved me hundreds of
Speaker 1: dollars with so you. Winding back to Friday night, I
Speaker 1: was driving to Louisville, Kentucky, about a two hour drive
Speaker 1: and might have been going seventy and get fold over
Speaker 1: and I think this is it. I'm gonna have to
Speaker 1: take out extra loans, get another job, My insurance is
Speaker 1: gonna go up. And then I remember what Chuck said
Speaker 1: about getting out of his speeding tickets and just surrendering
Speaker 1: myself to the law, so I thought, why not give
Speaker 1: it a try, and it worked. Not only do I
Speaker 1: did I not have to pay for a park or
Speaker 1: for a speeding ticket, but you saved my insurance from spiking.
Speaker 1: I'll always remember this in future situations. But of course
Speaker 1: I'm gonna work in my lad foot first. Thanks so
Speaker 1: much for the advice, and thank you for the podcast.
Speaker 1: Guys listen almost every day. I don't know what my
Speaker 1: morning commute would be without it. That is from Camber Soulberger.
Speaker 1: Nice first of all, Camber, great name, Cambra Solberger, even
Speaker 1: greater name, that's one of the great names. And then
Speaker 1: uh yeah, Chuck getting you out of a ticket. That's
Speaker 1: just an all around fantastic listener mail Charles Greed. Well,
Speaker 1: if you want to get in touch with us, like
Speaker 1: Cambert Limburger Camembert Limburger did, you can go on to
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