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Speaker 1: website apart. Welcome to Stuff you Should Know from House
Speaker 1: Stuff Works dot com. Hey, I'm welcome to the podcast.
Speaker 1: I'm Josh Clark, and there's Charles W. Chuck Bryant and
Speaker 1: uh guests. Who's over there being quiet as a church mouse.
Speaker 1: The producer who may or may not exist, Jerry. People
Speaker 1: still think that. I think a few people do. Yeah,
Speaker 1: she's real, says you. She's real because I can always
Speaker 1: smell her me. So from here? Oh man? I um,
Speaker 1: so I like avocado a lot, right, So I like
Speaker 1: avocado a lot. Basically an avocado a day. Um, And
Speaker 1: normally I make guacamole. As you know, I make probably
Speaker 1: the best guacamole on the planet. Sometimes, okay, we'll have
Speaker 1: a guac off one day. Well, yeah, but it's personal taste,
Speaker 1: you know, you know that whole thing. Remember, no taste
Speaker 1: is absolute. Um. So it's sometimes it's just too much
Speaker 1: to make guac sure, right, that's where avocado toast comes in. Yeah,
Speaker 1: it's so easy, but and it's totally different too. So
Speaker 1: if you start to get sick of guacamole, you like,
Speaker 1: I'll have some avocado toast. Anyway. The upshot is is
Speaker 1: I recently took antibiotics, which are disgusting poison, but just
Speaker 1: had to have them this time because my body would
Speaker 1: not get rid of whatever had um. And so I've
Speaker 1: been like repopulating my gut flora with fermented stuff like
Speaker 1: mis Took some miso, put it in some avocado, whipped
Speaker 1: it up, spread it on some toasts. It was great.
Speaker 1: And avocado, being a fibrous vegetable, should be a prebiotic.
Speaker 1: It will probably provide the conditions for that miso to
Speaker 1: ripen into some really top notch gut flora. Well I'm
Speaker 1: grossed out now, are you really? Yeah? I found that
Speaker 1: stuff fascinating. All that your gut flora. It's a matter
Speaker 1: of personal taste. I guess. It's like people like the
Speaker 1: smell of their own poop. That's not two different things.
Speaker 1: Do you like the smelling your own poop? Great? Really? Yeah?
Speaker 1: I like all my smells. I got you. Do you
Speaker 1: like ice? Ay? Just I do? We're in one yeah,
Speaker 1: well can we be in a noisy age? It's hottest wherever, right,
Speaker 1: but the climb is not changing. Why this summer has
Speaker 1: been awful? Yeah, supposedly every year we just keep getting
Speaker 1: hotter and hotter. Yeah, And I'm like, I have a
Speaker 1: feeling here and Georgia, it's going to be hot into October.
Speaker 1: I noticed the change take place to day Oh really?
Speaker 1: Uh not me. I was out there this morning, but
Speaker 1: momo out well yeah, and I was like, oh, it's
Speaker 1: not muggy night. Nights are getting cooler. That's where it
Speaker 1: starts to change. Yeah, but it's still like up in
Speaker 1: the nineties during the day. During the day is still
Speaker 1: kind of nasty. But it feels different to me, like
Speaker 1: the air feels different. Yeah, not me yet. Yeah, that
Speaker 1: that first fall blasts I haven't experienced. Maybe it's seeing
Speaker 1: like cinnamon brooms and Kroger that's put me in the
Speaker 1: fall mood already. I'm just noticing it where it's not
Speaker 1: the Christmas decorations, right, yeah, Halloween stuff's been out since August. Man,
Speaker 1: just ridiculous. So back to ice ages. Um, like you said,
Speaker 1: we are actually in an ice age. To be specific,
Speaker 1: we are in the Holocene epoch right, yes, which features
Speaker 1: the Quaternary ice age, and specifically we're in the flandry
Speaker 1: and interglacial period. But still, even though it's interglacial, it's
Speaker 1: still an ice age that we're in. It's a mouthful,
Speaker 1: it is. Who wrote this? Was this? Molly? Molly Edmonds,
Speaker 1: our dear old friend. Yes, she she put out quality
Speaker 1: she did. Um. Yeah, Molly points out quite astutely that, uh,
Speaker 1: you know, if you look at Antarctica in Greenland, you
Speaker 1: still see ice sheets and um ice ages. Though are
Speaker 1: it's not you know, we don't have to have the
Speaker 1: entire or a third of the earth covered in ice
Speaker 1: to be in an ice age, because within an ice
Speaker 1: age there's periods of cooler weather and warmer weather, and
Speaker 1: right now that you know, glacials and interglacials respectively, and
Speaker 1: right now we're in an interglacial. That's all it is.
Speaker 1: But like I said, when people look around, they don't
Speaker 1: think of as being in an ice age, because we're
Speaker 1: just during one of those warmer periods, right. But I
Speaker 1: think so. I was reading this New Scientist article about
Speaker 1: I think it's called the History of Ice on Earth,
Speaker 1: and they said that there are basically three settings that
Speaker 1: the Earth has. UM greenhouse, which is basically there's no
Speaker 1: ice anywhere on Earth. UH. Ice house which is like
Speaker 1: an ice age glacial period where there is ice even
Speaker 1: like today there's ice on the Arctic and Antarctic caps
Speaker 1: right um. And then there's a snowball um setting the
Speaker 1: most fun of all, which is like the entire planet
Speaker 1: is frozen over the least fun of all. There have
Speaker 1: been periods of Earth's history where the whole thing was
Speaker 1: just a giant ball of ice. Yeah, if we want
Speaker 1: to talk about the you know, the I don't know
Speaker 1: if you want to call it the Big Ice Age.
Speaker 1: But when we think of the term ice age, we
Speaker 1: most people are probably talking about the one that began
Speaker 1: about seventy thousand years ago, uh during the Pleistocene era
Speaker 1: lasted about sixty thousand years UH. And if you're talking
Speaker 1: about the United States, uh, and the four major glaciations
Speaker 1: they hit the Midwest, the Nebraska and the Kanson the
Speaker 1: Illinois and the famous Wisconsin glaciation. Yeah, that's the one
Speaker 1: that just ended that. We just came out of the
Speaker 1: Wisconsin one, that's right. And they call him this because
Speaker 1: that's where they were geographically. Well that's where I think
Speaker 1: the greatest evidence of them has been discovered. Right. So, um,
Speaker 1: and in all this it's kind of confusing, actually, but
Speaker 1: just just the the current ice age that we're in
Speaker 1: started two point five eight million years ago, right, and
Speaker 1: again it's still going two point five eight million years
Speaker 1: to present, the quaternary ice age. Um. And so those
Speaker 1: little other subdivisions have to do with when the ice
Speaker 1: has been relatively scarce or when it's been all over
Speaker 1: the place. And then to make it even more slightly,
Speaker 1: can using during periods of glaciation. There's even periods where
Speaker 1: the glaciers retreat and advance. That's stadial and interstadial periods,
Speaker 1: and those tend to be a little more local. Uh,
Speaker 1: And and happened a lot a lot more quickly, and
Speaker 1: glacial or in an interglacial period, happened on the scale
Speaker 1: of tens of thousands of years. Yes, that's right. And uh,
Speaker 1: this is nothing new, Like you said, this has been
Speaker 1: going on since there was a planet Earth. But um,
Speaker 1: actually recognizing and and what is an ice age just
Speaker 1: sort of on the newer front, because in the old days,
Speaker 1: you know, they would see a big rock and they
Speaker 1: would say, boy, the thing looks like it slid down
Speaker 1: that mountain there, because you can see that mountains all
Speaker 1: carved up and this rock shouldn't be here, and that's weird.
Speaker 1: So that was the Great Flood of Biblical Times. We
Speaker 1: treated an episode on Yeah, that was a good one,
Speaker 1: and um, so that was kind of how things were explained,
Speaker 1: how these things ended up places where they probably did
Speaker 1: not start out. Yeah, people noticed that there was just
Speaker 1: weird stuff going on in the geography around them, right, Um,
Speaker 1: but they didn't they didn't place it correctly. Until it
Speaker 1: turns out the Swiss peasantry and some German peasants as well,
Speaker 1: started to notice that their glaciers were receding. And as
Speaker 1: their glaciers receded up there and say the Alps, it
Speaker 1: left some markings that they noticed also the same kind
Speaker 1: of markings further down the mountain. So the Swiss peasants
Speaker 1: put two and two together and said, you know what,
Speaker 1: I think the glaciers used to be way, way bigger
Speaker 1: than they are today, and that maybe that is what
Speaker 1: explains these boulders that shouldn't be here being here in
Speaker 1: the middle of this field. And I guess from what
Speaker 1: I can gather, it was kind of like common folk
Speaker 1: wisdom in some areas of like the Swiss Alps, long
Speaker 1: before science understood it. And it was actually a Swiss
Speaker 1: geologist who was the first one to advance a genuine
Speaker 1: bona fide hypothesis for ice ages. Yeah, Lewis Uh, I
Speaker 1: guess sees is how I'm gonna pronounce that. And um
Speaker 1: he in seven presented um his ideas about this glacial
Speaker 1: activity at a conference, the science conference, and everyone was like, yeah,
Speaker 1: m I don't know. I don't know about you. I
Speaker 1: don't know about that. Well, they didn't know about him.
Speaker 1: He was he was a smart guy, right, he was established.
Speaker 1: But they're like, you're just go back to your opium
Speaker 1: pretty much. And apparently his his first theory was that
Speaker 1: there there have been an ice age. It happened like
Speaker 1: very quickly. Yeah, he was off basically like night and day. Uh,
Speaker 1: and and that um it had followed a catastrophe, right, Yeah.
Speaker 1: I wonder if he would have that seems like the
Speaker 1: one thing that might have put them off. It was
Speaker 1: how unlikely that sounded right? Because he was wrong? Like
Speaker 1: I won. If you would have said it happened slowly
Speaker 1: over time, let's say, yeah, they may have said like,
Speaker 1: oh well, I'm not buy that he's presenting his finding.
Speaker 1: He's like, what do you guys want to hear? But
Speaker 1: I'll massage it in that way. Yeah, it happened overnight
Speaker 1: and they all just cross their arms. He goes or
Speaker 1: overnight over a very long period of time. Uh so
Speaker 1: before him though, um, quite a few years before him,
Speaker 1: there was a scotsman. Oh yeah, born in Edinburgh, Edinburgh,
Speaker 1: buried at Greyfriars Kirkyard. Wow, which did you ever go there?
Speaker 1: I walked past it. I never made it in Okay,
Speaker 1: well my hotel was right there, so I walked through it. Amazing,
Speaker 1: amazing cemetery. I went to Marry King's close instead, which
Speaker 1: is pretty awesome too. Oh you had to go to
Speaker 1: one or the other. They're close to each other. Um,
Speaker 1: there's only so much time in the day. Off not
Speaker 1: close enough? Uhive a man named James Hutton, uh man,
Speaker 1: this guy was He was a stud the father of geology.
Speaker 1: He had this idea that he he was one of
Speaker 1: the first people to look around and say, you know what,
Speaker 1: the Earth is always changing, Like if you look around
Speaker 1: and pay attention, look at it, that birds just died.
Speaker 1: Like he might sit for days and look and wait
Speaker 1: for something to move. But he said, the Earth is
Speaker 1: constantly changing, and I have an idea that it's probably
Speaker 1: always been this way. So if we look at what's
Speaker 1: going on now and we apply that to the past,
Speaker 1: we might come up with some pretty interesting stuff here, right. Yeah,
Speaker 1: he said that there's basically clues to the past in
Speaker 1: the present. Yeah, just like, look what's going on around you.
Speaker 1: This might have happened ten thousand years ago as well,
Speaker 1: and that might explain something like that boulder being someplace
Speaker 1: different exactly. And we keep going to the boulders. But
Speaker 1: the boulders are actually some really really high quality evidence
Speaker 1: for ice ages in general. Um, there's there. There's actually
Speaker 1: a term for it among people who study ice ages.
Speaker 1: They're called erratics. And an erratic is a very very
Speaker 1: heavy boulder, way too heavy to have been moved by humans.
Speaker 1: Um that is also too far from its point of
Speaker 1: origin to just say rolled downhill it doesn't make any
Speaker 1: sense that it's there, which is why it's called n erratic.
Speaker 1: There's some very famous ones. Um, there's one in the
Speaker 1: Swiss Alps. Uh, well, I'm sure there's many, but there's
Speaker 1: one in particular. This article mentions that's in the Swiss
Speaker 1: Alps that is, um, about fifty miles from its point
Speaker 1: of origin. There's one in Central Park that is many
Speaker 1: miles away from its point of origin. In New Jersey,
Speaker 1: it moved, tried to make it in the big city.
Speaker 1: It was a bridge and tunnel boulder, right. So, and
Speaker 1: that's actually one of the one of the ways the
Speaker 1: Germans figured out that there was such a thing as
Speaker 1: ice age because they said, see that bowler there in
Speaker 1: that field, I'm pretty sure that skinnin Avian rock, and uh,
Speaker 1: sure enough they were correct. And so you start to
Speaker 1: put all this stuff together, huge bowlders being moved, Um,
Speaker 1: valleys between mountains, carved out in a U shape rather
Speaker 1: than that telltale V shape that a river carves out. Um.
Speaker 1: These are clues. They're not well they are erratics, but
Speaker 1: their clues into the past. Yeah that when you start
Speaker 1: to put all of them together. The only thing that
Speaker 1: that really explains them, is huge, massive movements of glaciers.
Speaker 1: Glacial movement. Yeah. And and when you study that stuff
Speaker 1: and you look at these grooves and you study the boulders,
Speaker 1: you can actually make calculations. And it's amazing that way
Speaker 1: back then they were able to make these calculations. Uh.
Speaker 1: Agazz in particular and some other guys got together and
Speaker 1: they said that the present ice age at its peak,
Speaker 1: I guess, um, was about a mile thick of glacier
Speaker 1: A mile of ice. Yes, it's amazing yeah. Um. And
Speaker 1: further studies have concluded that in the last ice age, um,
Speaker 1: I guess there was Wisconsin glaciation. Um. The the about
Speaker 1: a third of the earth was covered in glaciers. Have
Speaker 1: we said that glacier as yet? I mean, it almost
Speaker 1: goes without saying, but just in case. Yeah, it's just
Speaker 1: really densely packed snow it is, and it snow that
Speaker 1: that isn't allowed to melt. It's it's cold enough so
Speaker 1: that it never fully melts. At the base, it forms
Speaker 1: to ice, and on top you've got more and more snow,
Speaker 1: and as more and more snow doesn't melt, the ice
Speaker 1: builds up thicker and thicker and just from the sheer
Speaker 1: force of these things mass encountering gravity, they can actually move.
Speaker 1: They're like very slow most of the time, very slow
Speaker 1: moving rivers of ice on a massive scale. Yeah, and
Speaker 1: and well we'll get to that later. I was gonna
Speaker 1: tease something out. Uh, should we take a quick break?
Speaker 1: All right, we'll take a break and we'll get back
Speaker 1: to a little more amazing glaciers. All right. So we've
Speaker 1: talked about the sheer size a mile a mile thick
Speaker 1: of ice. Yeah, and I said, like a third of
Speaker 1: the Earth. I think it covered seventeen million square miles
Speaker 1: of the planet during the last glaciation cubic miles, my friend,
Speaker 1: cubic miles, right, So junk is deep. Yeah, a mile deep. Man,
Speaker 1: That is nuts. Uh. So Antarctica had about ten percent
Speaker 1: more ice than it does now. And the big change
Speaker 1: with the big difference, Uh, what sets that ice age
Speaker 1: apart was the amount of activity in the northern hemisphere.
Speaker 1: It was very unusual to have the amount of ice
Speaker 1: in North America and Europe extending down like through the
Speaker 1: midwest of the United States. It was it was a
Speaker 1: new scene, a new chili scene. Ye, a whole new
Speaker 1: jam basically, and Chuck. I mean like it was largely
Speaker 1: in North America, but this also, um really covered a
Speaker 1: lot of Europe too. I mean like Ireland was covered,
Speaker 1: Germany was covered, Scandinavia was covered by ice, and basically
Speaker 1: everything that wasn't covered by ice, and Europe was a tundra,
Speaker 1: very much like Siberia is today. I actually I saw
Speaker 1: a documentary on I think it was a History Channel
Speaker 1: show about the Last Ice Age, and um, somebody figured
Speaker 1: out how much all of that ice weight are you
Speaker 1: ready for this? Basilion pounds? This might be more than
Speaker 1: a bazillion sixty eight thousand trillion tons was the total
Speaker 1: weight of the ice of the Earth on the Earth
Speaker 1: during the Last Ice Age, during the last place. How
Speaker 1: many maxes that have no idea? It's like more than
Speaker 1: a hundred uh well a North America loan about thirteen, Um,
Speaker 1: I'm sorry, about ten million square miles of ice. And
Speaker 1: you know this all came from the ocean, which means
Speaker 1: the ocean level was hundreds and hundreds of feet lower
Speaker 1: during this ice age. Yeah, like Canada is used to
Speaker 1: having large parts of it being covered by glacier, the
Speaker 1: United States is not used to this, but it came
Speaker 1: all the way down into the plains in some cases,
Speaker 1: and basically from New York over to Washington State totally
Speaker 1: covered by again a mile thick sheet of ice. Like
Speaker 1: you can ice skate on that without worry. You're not
Speaker 1: gonna fall through, it's still gonna crack. Did you ever
Speaker 1: do that growing up? Did Ohio? Like like you'd skate
Speaker 1: on lakes? Yeah, And we were never allowed to do
Speaker 1: that until my dad went out and stomped on it,
Speaker 1: like jumped up and down, and if he didn't go through,
Speaker 1: then we were allowed to skate. He's like, kids, if
Speaker 1: I die right. It wasn't. It wasn't the most fool
Speaker 1: proof technique, but it was nice and dad to do
Speaker 1: that for us. I don't know, think I'm not much
Speaker 1: of a worry word, but I'm that still would have
Speaker 1: like creeped me out. I've seen enough movies, you know,
Speaker 1: left under ice. So the Mammi River would freeze over,
Speaker 1: but we weren't allowed to skate on the river. Some
Speaker 1: people did, we weren't allowed to. Instead, there was a
Speaker 1: golf course with ponds that would freeze pretty good, pretty good.
Speaker 1: There was your You weren't going to fall through these
Speaker 1: small ponds pretty rough though, right, like skating on it's
Speaker 1: not it depends it depends on and I don't remember
Speaker 1: what it depends on. Yeah, it's it's never like an
Speaker 1: ice drink. But certain type of weather, maybe non windy weather,
Speaker 1: I think is what it was, because then like if
Speaker 1: there was kind of like a choppiness to it from
Speaker 1: the wind, it could freeze like that freeze choppy, Whereas
Speaker 1: if it wasn't windy, I would guess it would it
Speaker 1: would be smoother. So sometimes it was pretty smooth. Other
Speaker 1: times you're like, I can't even skate on, but your
Speaker 1: dad would drive a zambonie out there and fix it
Speaker 1: all up. It over and if the zamboni didn't fall through,
Speaker 1: then we were allowed to skate, right. I just picture
Speaker 1: of the zamboni falling through. But it's a little pond,
Speaker 1: so you're a'd still like just a bove. I feel
Speaker 1: like I missed out, though, I mean not that life
Speaker 1: is over. You can still skate on ponds. I don't
Speaker 1: picture myself going to Minnesota in the in the winter.
Speaker 1: Give it a try. The trade off it wasn't It
Speaker 1: wasn't a very good trade off because the winners are
Speaker 1: pretty brutal. Yeah, like if you have local ponds that
Speaker 1: freeze over, you're cold too. I still feel like I
Speaker 1: missed out. Yeah, I mean you're fine. It wasn't that
Speaker 1: big of it was just teasing when I said, you
Speaker 1: did miss that. Uh all right, So people are skating
Speaker 1: all over the world. A third of the world people
Speaker 1: are ice skating on during during the ice age UM
Speaker 1: and like we mentioned these things, UM they've been described
Speaker 1: as bulldozers just plowing through uh the earth basically um
Speaker 1: leaving large swaths they call it glacial till. This debris
Speaker 1: that they leave behind, and these are you know, once
Speaker 1: you figure out how it works, the evidence is every
Speaker 1: where of exactly what happened. Yeah, Because as these glaciers
Speaker 1: move and that ice that has formed the basis of
Speaker 1: the glacier is in contact with the earth below it,
Speaker 1: it's picking up all sorts of crud that all that
Speaker 1: to breathe that glacial till you said, erratic boulders. And
Speaker 1: as it's doing this, it's actually creating a um a
Speaker 1: scrubbing mechanism. Right. So, like you said, if you look
Speaker 1: around at mountains and and and valleys with exposed rock
Speaker 1: that were um rubbed by glaciers. There's gonna be crazy
Speaker 1: grooves worked into them. Some look like roads almost, yes, um,
Speaker 1: some are kind of polished and rounded, And it's all
Speaker 1: from this glacial activity rubbing stuff over the tops of
Speaker 1: these mountains. It's pretty interesting stuff. And then other things
Speaker 1: like you'll know, you know, you'll see like a movie
Speaker 1: where um, this incredibly beautiful uh like river Valley has
Speaker 1: just gravel everywhere, like just scattered all all throughout, like
Speaker 1: the valley floor. That's not supposed to be there. The
Speaker 1: glacier deposited that. That's right, it's more evidence of the
Speaker 1: ice age. Yeah, that's interesting to think of it. It's
Speaker 1: not supposed to be there. No, and you think of
Speaker 1: that like that's what that's what that looks like. You know,
Speaker 1: of course that's what it's. That's that's that's supposed to
Speaker 1: be there. But no, it's technically not. Had we not
Speaker 1: had um these glaciation events, that stuff wouldn't be there.
Speaker 1: And that fascinating earth science. Uh is that your favorite science?
Speaker 1: I think it's become it. Yeah, yeah, it really does
Speaker 1: get me jazzed, all right. So it wasn't just um,
Speaker 1: the direct path of these glaciers that was affected out
Speaker 1: on the edges of these massive moving sheets of ice. Um,
Speaker 1: you had things like arctic deserts, and you had these
Speaker 1: big areas of dusty wind. Uh. And there's actually a
Speaker 1: few ways to pronounce this l O E s s
Speaker 1: heard everything from lowest to lows to less I like lowest, Yeah,
Speaker 1: like lowest too. Um covering all over the earth basically,
Speaker 1: and this is created by those glaciers just like grinding
Speaker 1: into the earth. Yeah, um, stirn everything up right, and
Speaker 1: then the wind just comes and picks it up, the
Speaker 1: finest of the particles and just deposits them. So in
Speaker 1: some places you had so if if your area wasn't
Speaker 1: covered by glacier, that didn't mean you weren't affected by
Speaker 1: the glaciation, because you would have these lowest deserts are
Speaker 1: glacier glacial deserts that formed. And in some places the
Speaker 1: lowest was like twenty ft thick, and apparently it's still there.
Speaker 1: In much of the Midwest, the sub straight below the
Speaker 1: soil is lowest, deposited from these lowest deserts UM. And
Speaker 1: so you would think when you hear about this kind
Speaker 1: of activity that it had to be like hundred degrees chillier, right,
Speaker 1: or fifty or forty even, but it was only about
Speaker 1: ten degrees fahrenheit about five point six celsius lower uh
Speaker 1: than temperatures now, which it's it wouldn't think that that
Speaker 1: would be enough, right, But it's not all just about
Speaker 1: the temperature. That's kind of the point. No, The point
Speaker 1: that Molly makes is that it's not like, oh, it's
Speaker 1: just so much colder than it was before all the time.
Speaker 1: The key to an ice age um forming glaciers a
Speaker 1: glacial period is that this the time when it's supposed
Speaker 1: to actually melt, is colder than usual, so that there's
Speaker 1: less melt than than before. And the less melt you have,
Speaker 1: the more chance you have for snow to fall and
Speaker 1: make up for whatever melted and actually add to it,
Speaker 1: which means that the glaciers growing. As long as more
Speaker 1: snow is added to the glacier than it loses during
Speaker 1: say the summer months, your glaciers growing. Yeah, and if
Speaker 1: it's not losing much, it doesn't take much snow. And
Speaker 1: this this cycles arts. There's something called albedo or albedo
Speaker 1: albedo and it's uh, it's the real reflectivity of ice.
Speaker 1: And you know once this ice gets going, it's reflecting
Speaker 1: away the sun. So it's while you're hotter in the
Speaker 1: summer wearing a black T shirt than a white T shirt. Yeah,
Speaker 1: and it's just it creates that cycle basically where it's
Speaker 1: all just compounding, all these different elements coming together absolutely
Speaker 1: to make ice super thick. So you have if you
Speaker 1: have a glacier form on planet Earth and it reflects
Speaker 1: a bunch of sunlight and makes it colder, well that's
Speaker 1: gonna create the conditions for other glaciers to form too,
Speaker 1: So it has a compounding effect as well that albedo does.
Speaker 1: All right, well let's take a break and we're gonna
Speaker 1: come back and talk about a very famous Serbian mathematician.
Speaker 1: All right, so I said, famous Serbian mathematician. Had you
Speaker 1: already heard of this guy? Yeah? Really, i'd heard. I
Speaker 1: had heard about the Milankovich cycles. Um. So his name
Speaker 1: was Milutin Milankovic. And it's amazing to me that in
Speaker 1: the nineteen twenties, people like well, i'll just say him,
Speaker 1: was able to figure out with a lot of accuracy, um,
Speaker 1: the Milankovich cycles. Basically, he said, you know what, I
Speaker 1: have a theory on why these these summers are cooler,
Speaker 1: and why this ice age happened, And it's not just
Speaker 1: the temperatures, but it's because of the Sun's relationship to
Speaker 1: the Earth and how much sun the Earth is getting
Speaker 1: UH during the summer months. So he came up with
Speaker 1: three different factors, the tilt UH in the Earth's axis,
Speaker 1: the way the Earth wobbles on that axis, and then
Speaker 1: how close we are to that heat, how close we
Speaker 1: are the sun. He plugged those into a mathematical formula
Speaker 1: and he came up with every one hundred thousand years,
Speaker 1: he's predicting that we're going to get these ice ages.
Speaker 1: Pretty amazing math for back then, it is, especially if
Speaker 1: you go back. So he figured this out, and then
Speaker 1: they went back and looked at the fossil record, the
Speaker 1: geological record, because when he was working, they didn't have
Speaker 1: this understanding. He wasn't like proving that like yes, predicting right.
Speaker 1: So then um about that time and like the well
Speaker 1: after that time, but in like the forties and fifties,
Speaker 1: the US was building army bases all over the world
Speaker 1: in some really crazy places, including the Arctic, and um
Speaker 1: some scientists went along and started taking core samples from
Speaker 1: those places. And they found air bubbles trapped in there
Speaker 1: that were from like a million years ago, Like the
Speaker 1: air was a million years old and it was untouched
Speaker 1: virgin air. And um. They found that they could do
Speaker 1: all sorts of stuff and learn all sorts of things
Speaker 1: from this air. And one of the things they found
Speaker 1: was the basically the time stamp for the ice ages
Speaker 1: during the Quaternary period. And they found out that in
Speaker 1: the first two million years, the first two thirds of
Speaker 1: the Quaternary um ice age, the ice ages, glaciation occurred
Speaker 1: every forty one years. And yeah, yeah, that's what I said.
Speaker 1: He's like, but wait for it, and they said, okay,
Speaker 1: in this this most recent million years, it switched to
Speaker 1: a hundred thousand years. And he just said his arms crossed,
Speaker 1: very smugly. Yeah. Um. And everybody said, that's amazing, that's fantastic. Scientists,
Speaker 1: you guys in the lab coats what causes an ice age,
Speaker 1: And there's just crickets coming back from the scientists, and
Speaker 1: there still is today. Actually, actually, no, that's the opposite,
Speaker 1: is true. Not crickets, but a ton of different answers
Speaker 1: and a ton of different theories. Yeah, lots of crickets,
Speaker 1: but not quite either. What would be the animal that
Speaker 1: would talking crickets, Jimmy crickets everywhere? Man, that I was annoying,
Speaker 1: putting forth, putting forth theories and and as with most things,
Speaker 1: we usually kind of center on. I bet it was
Speaker 1: like most of these things put together, which most scientists
Speaker 1: do well, dude, I was thinking about this, and I
Speaker 1: was like, yes, chaos theory, Like, we have such a
Speaker 1: propensity as humans to be like there's one true explanation,
Speaker 1: there's one factor that explains everything, and that is just
Speaker 1: not the case. This is a perfect example of that.
Speaker 1: I wonder if that's a tendency for humans to want
Speaker 1: to be right. Like the people actually doing the research
Speaker 1: say like, no, this is my ideas. Yeah, I think
Speaker 1: that's part of it, But I think it's more are
Speaker 1: just like our brains are wired to find like the
Speaker 1: least common denominator to find, um, the easiest route. Yeah,
Speaker 1: maybe you know, just for efficiency's sake, that makes sense.
Speaker 1: I kind of like the idea of like, I'm hands
Speaker 1: across America. Did you participate in Hands across America? Not
Speaker 1: hated it back then, but oh man, I get it now.
Speaker 1: I'm just kidding. I think I did actually, yeah, there
Speaker 1: was huge, huge gaps, but it was still pretty great.
Speaker 1: We should do a show on that. I didn't know
Speaker 1: there were gaps, of course there were oh yeah, pretty
Speaker 1: pretty big ones. Yeah, there was at no point complete.
Speaker 1: I think our school did it. Wasn't that the deal?
Speaker 1: Like probably did this church, church, hippie church. I don't
Speaker 1: know if my church might have been like, no, we're
Speaker 1: not holding hands. You could be holding hands with an atheist.
Speaker 1: Probably you wouldn't even know it. That probably would have
Speaker 1: been the case. All right. So another theory is, um,
Speaker 1: we've talked a lot about plate tectonics and our geez
Speaker 1: and the volcano episodes and what else the plate tectonics episode.
Speaker 1: Did we do one on that specifically among the close
Speaker 1: to episodes? Man, I don't remember where it first popped up,
Speaker 1: but it's definitely come up. Clapped up another one of
Speaker 1: your non pun puns. Yes, I hope. I'm like creating
Speaker 1: a pretty a pretty extensive case for the fact that
Speaker 1: all of my puns are accidental. I don't think like
Speaker 1: that accidental puns a good banding too. Ironically, it's okay.
Speaker 1: Uh So plate tectonics is another theory. Basically, you know,
Speaker 1: everyone knows when you get to a higher altitude, it's
Speaker 1: going to be colder, and the conditions are more likely
Speaker 1: to for glaciers to form. And so when these these
Speaker 1: plates on the Earth are smashing together, everyone also knows
Speaker 1: from listening to our show, that's how we get these
Speaker 1: lovely mountain ranges and why there are higher altitudes. So
Speaker 1: that's another theory that that had a lot to do
Speaker 1: with it. Yeahs sense. Some scientists lay um the Quaternary
Speaker 1: ice Age, the whole shebang. That's two point five eight
Speaker 1: million year old ice age that we're in in still
Speaker 1: um basically at the feet of the creation of the Himalayas,
Speaker 1: where Asia and India collide, creating the Himalayas, and most
Speaker 1: importantly the Tibetan Plateau and this rising of land changing
Speaker 1: um the way that air moves across this huge portion
Speaker 1: of land Eurasia UM, and that it had an impact
Speaker 1: on climate, which has an impact on historical climate, which
Speaker 1: can change things, make things cold enough so that glaciers
Speaker 1: can form and really get a foothold. Right. More interesting, Chuck,
Speaker 1: is that it's apparently that's they're like, that's probably kind
Speaker 1: of a factor, but there's an even bigger factor that
Speaker 1: they think that came out of that upwelling of of earth.
Speaker 1: Bear with me. So, when earth meets earth and there's
Speaker 1: an upwelling and they form mountains or something like that, right,
Speaker 1: you know, the process of weathering, it's like breaking in
Speaker 1: genes or a strato various, Right, you break in mountains too. Well,
Speaker 1: that's actually a chemical reaction between like the air and
Speaker 1: the earth. And when rock is exposed, it becomes weathered
Speaker 1: because c O two reacts with the rock to basically
Speaker 1: form some sort of um uh equilibrium that's been interrupted
Speaker 1: or disrupted by the exposure of unweathered rock. Right. Well,
Speaker 1: to carry that out, c O two has to be
Speaker 1: drawn from the atmosphere, which means you're basically removing c
Speaker 1: O two from the atmosphere. When you create a new
Speaker 1: mountain mountain chain, and if you're talking about a mountain
Speaker 1: chain as extensive as the Himalayas, a lot of CEO
Speaker 1: two is going to be removed from the atmosphere. When
Speaker 1: you remove c O two from the atmosphere, you reduce
Speaker 1: the greenhouse effect. And when you deduced the greenhouse effect,
Speaker 1: the earth becomes cooler, possibly enough for an ice age.
Speaker 1: The timings right as well. The Himalayans formed right before
Speaker 1: the Quaternary Ice Age began. Ye aren't that amazing? It
Speaker 1: is or science? Uh. The other thing is dust atmospheric changes. Um,
Speaker 1: A lot of dust in the air is gonna keep
Speaker 1: the sun from shining down its warmth onto the Earth
Speaker 1: and keep temperatures cooler. And since I mentioned volcanoes, Um,
Speaker 1: there were a lot of volcanoes, a lot of activity
Speaker 1: that preceded the glacial ages. Um. But you know, launching
Speaker 1: a lot of dust in the air. I don't think
Speaker 1: it's coincidence. It's probably all tied in together. Yeah, I
Speaker 1: would guess that. Um, it's not just volcanic ash. I mean,
Speaker 1: there was just dust period, but the volcanic ash added
Speaker 1: to it, you know, right. And I think even after um,
Speaker 1: after the volcanoes stopped erupting gases that affect the atmosphere directly,
Speaker 1: they still interact with the water vapor in the atmosphere
Speaker 1: to mess with it in a continued way. UM. Sun
Speaker 1: spots are also another one too, right. Yeah, that's one
Speaker 1: of the main reasons for the little ice age, right. Yeah,
Speaker 1: but we talked about in the strata areas, so the
Speaker 1: little ice age. Um, so did you did you see
Speaker 1: that article I sent you? Yeah, it was pretty pretty interesting. Um,
Speaker 1: but there's a our understanding of the little ice age,
Speaker 1: which is not the best name for it, but there's
Speaker 1: a period should be little ice age. There's the from
Speaker 1: d to eighteen fifty. Europe in particular, well the northern hemisphere,
Speaker 1: but Europe got it pretty bad. Um. It was basically
Speaker 1: what amounts to an ice age for for this area. Um,
Speaker 1: Greenland and Iceland were cut off by ice for months
Speaker 1: at a time. They used to grow wine in England,
Speaker 1: not anymore. Scotland they grew wine, Yeah, like bottles would
Speaker 1: just pop up out of the grounds. The Highlands of
Speaker 1: Scotland would be locked into ice at like and up
Speaker 1: the Baltic Sea froze over. Yeah, the canals and the
Speaker 1: Netherlands routinely froze. It was it was a really rough time. Well,
Speaker 1: it wasn't. It wasn't. It's pretty interesting because this article
Speaker 1: you sent, you know, points out a lot of the
Speaker 1: history that you know, it affected everything from shipping to
Speaker 1: crops to you know, people turning on one another in
Speaker 1: some areas then other areas things flourished, right, So apparently
Speaker 1: areas and groups that had access to extensive trade networks,
Speaker 1: especially with the South or the tropics. Um, they they flourished.
Speaker 1: But if you were in like a marginal area, say
Speaker 1: like the Alps, you were toast like you suffered from famine.
Speaker 1: Apparently glaciers were advancing enough that they were just overrunning
Speaker 1: towns and it sounds it sounds absolutely nuts, but actually
Speaker 1: glaciers can move surprisingly fast. Right. There was a glacier
Speaker 1: in Alaska in that was clocked advancing at ten a day. Yeah,
Speaker 1: I mean that's thirty ft a day. That's you can
Speaker 1: watch that happen. Yeah, or the very least you could
Speaker 1: set up your your inner volometer camera and watch it later.
Speaker 1: Or if you're just super patient, Yeah, I bet what's
Speaker 1: his name? Yeah, the scotsman. I bet James Hutton would
Speaker 1: have sat there and until he's yeah, you know, yeah,
Speaker 1: patient man. Uh what else do we cover the sun spots?
Speaker 1: Well not Yeah, I mentioned that that might have been
Speaker 1: why the little ice age happened. And by the way,
Speaker 1: we on the Strata Areas podcast heard from a lot
Speaker 1: of people about this double blind study that um or
Speaker 1: where they had musicians play um the stratas and uh,
Speaker 1: then against modern violins, and um, they preferred I think
Speaker 1: generally preferred the modern violin or so people are like, oh,
Speaker 1: you're just getting the brand name. That's kind of a
Speaker 1: reductive way to say it. Um. And and then afterwards
Speaker 1: to the violinists they serge them cough, they're like, it's folgers. Well,
Speaker 1: the other thing we heard from other people that said,
Speaker 1: these violinists know what they're testing. They're testing clearly testing
Speaker 1: and strata varius against a modern instrument. They don't just say, like,
Speaker 1: put on this blindfold and you're two violins, which one
Speaker 1: smells neater. So we probably should have included that, But
Speaker 1: I don't think that like settles it in any like
Speaker 1: scientific way or any Yeah, I saw in our research
Speaker 1: that that was not necessarily the case. It's on a
Speaker 1: number of different sources that that they can tell a
Speaker 1: difference that it is actually the best violins, and these
Speaker 1: are people that have, you know, opinions. It's not like
Speaker 1: you can't scientifically prove that because every person you pick
Speaker 1: out is going to have a different take on the matter.
Speaker 1: And we weren't poopooing modern instruments because clearly they're only
Speaker 1: a handful of strads out there being played, and there's
Speaker 1: many many orchestras and they're not playing like pawnshop violins,
Speaker 1: you know. Anyway, I just want to mention that, So
Speaker 1: these sun spots, right, there's actually a cycle that was
Speaker 1: recognized by a British astronomer named E. W. Maunder. It's
Speaker 1: pretty British name, and he was living during the Little
Speaker 1: Ice Age UM and he noticed. Yeah, he was like, well,
Speaker 1: like how it's cold you can ice skate on a pond. Um.
Speaker 1: He noticed that the so the Little Ice Age should
Speaker 1: actually be called the little period where it was pretty
Speaker 1: cold and then really really cold and two different points,
Speaker 1: and those points were between twelve ninety and undred and
Speaker 1: then sixty five and seventeen fifteen. It was really cold,
Speaker 1: like kind of ice ages conditions for real UM. And E. W.
Speaker 1: Maunder noticed that, especially the time when he was alive
Speaker 1: during between the sixteen and seventeen fifty period seventeen fifteen period, UM,
Speaker 1: sun spots were not nearly as active. And he was like,
Speaker 1: I wonder if this correlates to little ice ages, and
Speaker 1: it would make sense, even though it makes sense in
Speaker 1: a really weird way, a roundabout way. Actually, Yeah, sun
Speaker 1: spot I guess we should just say what that is.
Speaker 1: It's a dark spot, a cooler spot on the Sun.
Speaker 1: But the key there is it contains magnetic energy. So
Speaker 1: you would think that sun spots are cooler than the
Speaker 1: rest of the Sun. So how would that well wait,
Speaker 1: now I've got it backwards, No, you got it? Yeah? Yeah,
Speaker 1: so how would that keep it warmer on Earth? But
Speaker 1: it's about that magnetic field cutting through cloud cover or
Speaker 1: cutting the cloud cover, right, So less cloud cover means
Speaker 1: that the heat from the Sun isn't trapped, it just
Speaker 1: escapes into space. Counterintuitive, but it makes sense. Yeah, because
Speaker 1: these sun spots are big enough that when it's facing Earth,
Speaker 1: it's putting out less heat energy. So you would think
Speaker 1: it would it would directly cool it. It indirectly cools it. Right. Weird,
Speaker 1: It is weird, but amazing earth science. Uh So, whether
Speaker 1: or not we're headed for another one is a lot
Speaker 1: There's a lot of debate on that because some people say, well,
Speaker 1: there's no strict definition even what an ice age is,
Speaker 1: so who's to say. Other people say, now you know what,
Speaker 1: humans have cause uh such an impact here that there
Speaker 1: probably won't be another ice age. It's extremely possible that
Speaker 1: we have altered the climate enough that we're not going
Speaker 1: to see like we may have ended on our own
Speaker 1: the Quaternary ice age. It may be over now or
Speaker 1: on the way to being over, in which case we
Speaker 1: have a whole other set of problems to deal with,
Speaker 1: but not an ice age, not glaciers. Um. There was
Speaker 1: actually a study that made the rounds, I think this
Speaker 1: year or last year, that really drummed up a lot
Speaker 1: of media engine because these researchers said that they predicted
Speaker 1: a period of very low sun spot activity in thirty
Speaker 1: years because we're due for one technically, right were a
Speaker 1: year point, Yes, yeah, we're due for another glaciation event.
Speaker 1: And these people said, well, there's gonna be sun spots
Speaker 1: in thirty years, and the media took it and said
Speaker 1: there's gonna be another ice age in thirty years. Um,
Speaker 1: And that's not necessarily the case. It's a pretty big
Speaker 1: leap from saying, yes, there's low sun spot activity, so
Speaker 1: we're gonna have an ice age. But if we hadn't
Speaker 1: burned all those fossil fuels, maybe that would be the case.
Speaker 1: Maybe we would start to see glaciation beginning again in
Speaker 1: about thirty years. Again we're probably not going to because
Speaker 1: we've raised the temperature of the planet by it a
Speaker 1: full degree celsius since night UM, so it's possible we
Speaker 1: won't ever see an ice age again, which is sad
Speaker 1: because some people say that it was this last um,
Speaker 1: this ice age, not just the last glaciation event, but
Speaker 1: the Quaternary ice Age as a whole that pushed humans
Speaker 1: to evolve to the wonderful, amazing specimens we are today. UM.
Speaker 1: A lot of advancements happened because of it. Adaptations and
Speaker 1: animals and early humans there were there was movement among
Speaker 1: around Earth because the sea levels were a lot lower,
Speaker 1: so you could make your way around bigger parts of
Speaker 1: the Earth. They weren't cut off like before like they
Speaker 1: are now. UM. Apparently, our brains grew tremendously in size
Speaker 1: during the Quaternary Ice Age at a in a time
Speaker 1: period that correlates with it, and one hypothesis is that
Speaker 1: the cooler temperatures allowed us to dissipate heat more naturally
Speaker 1: and to save our energy or use more energy, which
Speaker 1: would allow our brains to grow. Interesting and then other
Speaker 1: people say, well, you know what, the chro magnets also
Speaker 1: invented the sewing needle during this time because of the
Speaker 1: ice age, so that they could start sewing and close.
Speaker 1: Is the technology that allowed us to truly spread out
Speaker 1: over the earth. Yeah, because you could go live where
Speaker 1: it was cold, because you could make a big park
Speaker 1: out of a musk ox exactly. The muskox would say
Speaker 1: thank you for using me human. I don't know about that,
Speaker 1: But you got anything else? Nope, I think that's it. Man,
Speaker 1: This is good one, Chuck Uh. If you want to
Speaker 1: know more about ice ages, you can type those words
Speaker 1: into the search bar at how stuff works dot com.
Speaker 1: And since I said search parts, time for a listener. Mayo.
Speaker 1: Remember in the animal testing episode when I wondered aloud
Speaker 1: about the names of pork and beef and swine and
Speaker 1: all that stuff. I'm glad you're covering this. Apparently I'm
Speaker 1: the only person on the planet who did not know this.
Speaker 1: I didn't know it either, because we had a bunch
Speaker 1: of people right in Uh. And it's super interesting. So
Speaker 1: I picked one that was a good explanation from a
Speaker 1: gentleman in Bristol, United Kingdom. He said this before ten
Speaker 1: sixty six, in England, most people spoke a form of
Speaker 1: Germanic English Uh, and he says, by the way, I'm
Speaker 1: glossing over several centuries of linguistic history with that. However,
Speaker 1: after the invasion by William the Conqueror and his eventual coronation,
Speaker 1: Norman became the dominant language. UH. Norman is based on
Speaker 1: Northern French dialects, so would have used words such as
Speaker 1: mutton and booth for sheep and cows. These words were
Speaker 1: used by people who would have been able to afford
Speaker 1: to eat such food, namely the gentry. However, peasants who
Speaker 1: would have raised raise the animals still use the Germanic
Speaker 1: words like sheep and cow, and these words stuck. English
Speaker 1: is full of high and low words gentry or peasantry
Speaker 1: for similar meanings, with the high words being French based
Speaker 1: therefore Latin based. Really interesting. Um. Having stopped myself from
Speaker 1: going on, as is the subject I've always been obsessed with,
Speaker 1: and I hope that I have piqued your interest as well.
Speaker 1: Be warned the subject as a rabbit hole, I will
Speaker 1: also add I was gutted to miss your UK tour,
Speaker 1: and I hope you enjoyed it enough to come back
Speaker 1: one day. UM. I also cheekily plug Bristol as an
Speaker 1: amazing place to live and visit. Yeah, congratulations on your
Speaker 1: new sky pier. I don't heard of that. It's like
Speaker 1: a it's like a huge observation UFO that goes up
Speaker 1: on their coast. You can just see for miles and miles. Interesting.
Speaker 1: Much love to you both and thanks for doing what
Speaker 1: you do. Cheers. That is from Matt Gallaford of Bristol.
Speaker 1: Thanks Matt, We'll definitely be back. And thanks to everyone
Speaker 1: who wrote in with that good information. I wish I
Speaker 1: could have read them all. Uh. If you want to
Speaker 1: get in touch of us to let us know something
Speaker 1: we missed, or to tell us how grey we're doing,
Speaker 1: or well yeah, you can tweet to us at s
Speaker 1: Y s K podcast. You can also hang out with
Speaker 1: me at Josh Underscore, um Underscore Clark at on Twitter two.
Speaker 1: You can hang out with Chuck at Charles W. Chuck
Speaker 1: Brian on Facebook or our Stuff you Should Know page
Speaker 1: at Facebook dot com, slash stuff you Should Know. You
Speaker 1: can hang out with us on Instagram. You can send
Speaker 1: us an email to Stuff podcast at how Stuff Works
Speaker 1: dot com and has always joined us at our home
Speaker 1: on the web. Stuff you Should Know dot com For
Speaker 1: more on this and thousands of other topics. Is It
Speaker 1: How stuff Works dot com