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Where is most of Earth's water? · Daniel and Kelly’s Extraordinary Universe

• 0:08
  Speaker 1: Katie, I've got an alien hypothetical for you. Okay, I'm
• 0:12
  Speaker 1: i the alien in this hypothetical. No, you need the
• 0:17
  Speaker 1: aliens in this scenario. Cool. I've always wanted to get
• 0:20
  Speaker 1: drinks with aliens. So my question is, you're at the bar,
• 0:23
  Speaker 1: you're sipping space martinis, whatever. How do you describe to
• 0:27
  Speaker 1: aliens what Earth is like? Well, first of all, I
• 0:30
  Speaker 1: would be sipping a cosmic cosmo, and I would describe Earth. Well.
• 0:34
  Speaker 1: I'd want to be fair about Earth, but if I'm
• 0:37
  Speaker 1: too nice about it, they might want to take it
• 0:40
  Speaker 1: from us. So you know, I'd have to really walk
• 0:44
  Speaker 1: the line between playing it up too much, making it
• 0:47
  Speaker 1: sound too good, or making it sound too bad. Yeah,
• 0:50
  Speaker 1: that's a delicate balance between honesty and like a species
• 0:53
  Speaker 1: of self preservation. I guess I could tell them that
• 0:56
  Speaker 1: it used to be amazing and gorgeous, but then we
• 0:58
  Speaker 1: ruined it, and we're not going to get an invite
• 1:01
  Speaker 1: to their planet. I mean, would you invite us depends
• 1:06
  Speaker 1: on your cosmic cocktail recipe. Hi, I'm Daniel. I'm a
• 1:25
  Speaker 1: party gold physicist and a professor at UC Irvine, and
• 1:28
  Speaker 1: I would definitely not invite me to your alien planet.
• 1:31
  Speaker 1: And I am Katie Golden. I'm stepping in for Jorgey.
• 1:35
  Speaker 1: I host the podcast Creature Feature and the secret to
• 1:39
  Speaker 1: the Cosmic Cosmo is just a little bit of sprite.
• 1:45
  Speaker 1: What if you get to the alien planet and you
• 1:47
  Speaker 1: want to make this famous cocktail the reason they've invited
• 1:50
  Speaker 1: you across the light years, and they don't have sprite.
• 1:52
  Speaker 1: I mean, I guess Dr PIB would do fine. Well,
• 1:58
  Speaker 1: I'd be worried that if I got invited to that
• 2:00
  Speaker 1: alien planet, I'd bring with me some crazy microbes that
• 2:04
  Speaker 1: would like wipe out this alien species, and I'd be
• 2:07
  Speaker 1: so desperate to learn from them and talk to them
• 2:09
  Speaker 1: about the secrets of the universe, and then I would
• 2:11
  Speaker 1: be the cause of their death. That's why it's always
• 2:13
  Speaker 1: important to cover your mouth when you cough when you're
• 2:16
  Speaker 1: on an alien planet or on a train. Right. I
• 2:19
  Speaker 1: guess I'll just have to wear my mask or my
• 2:21
  Speaker 1: has mat suit when I finally read Aliens. But that
• 2:24
  Speaker 1: makes it quite difficult to drink a cocktail. It does,
• 2:27
  Speaker 1: so I think if we are going to master interstellar flight,
• 2:31
  Speaker 1: we may want to also master a mask that you
• 2:34
  Speaker 1: can drink through. Well. Welcome to the podcast. Daniel and
• 2:39
  Speaker 1: Jorge explain the universe in which we try to mix
• 2:42
  Speaker 1: up a cosmic cocktail of craziness for you. The ingredients
• 2:46
  Speaker 1: are all of the insanity in our universe, the crazy
• 2:49
  Speaker 1: things that the universe does, from bending space and time
• 2:52
  Speaker 1: to bizarre states of matter, to the squishiness of life
• 2:57
  Speaker 1: on Earth and how it all works he losing radiance.
• 3:00
  Speaker 1: We mix them all up with a healthy dose of
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  Speaker 1: silly jokes, and we serve it to you because we
• 3:04
  Speaker 1: think that everybody deserves to understand the universe, or at
• 3:08
  Speaker 1: least do share in our common ignorance and wonder at
• 3:12
  Speaker 1: its majesty and at its crazy insanity. Curiosity, and also
• 3:17
  Speaker 1: peach schnops are very important for the cocktail. Absolutely and horror.
• 3:22
  Speaker 1: He can't make it today. So I'm very grateful to
• 3:24
  Speaker 1: Katie for joining us today for an exploration of questions
• 3:28
  Speaker 1: about the universe. Thanks very much, Katie. Yeah, I'm so
• 3:31
  Speaker 1: happy we here, and I am excited to talk about
• 3:33
  Speaker 1: I guess we're talking about some form of cocktail, aren't we.
• 3:37
  Speaker 1: We are exactly today. We are exploring not the deep
• 3:41
  Speaker 1: depths of black holes or what's going on in far
• 3:44
  Speaker 1: away galaxies, but questions that are right here at home,
• 3:47
  Speaker 1: questions that are literally under our feet, and questions that
• 3:51
  Speaker 1: inform how we make our own cocktails. That's right. I
• 3:56
  Speaker 1: really like when we talk about Earth because I am
• 3:59
  Speaker 1: a little bit biased about Earth because I live on it,
• 4:03
  Speaker 1: and I do like it. You're in the pro Earth camp. Yeah, yeah,
• 4:08
  Speaker 1: it's very controversial. Take their Katie. I mean it kind
• 4:12
  Speaker 1: of is, no, but you're right. It's important that we
• 4:17
  Speaker 1: understand not just our origins here on Earth, but how
• 4:20
  Speaker 1: things here on earthwork. From a practical point of view,
• 4:23
  Speaker 1: we need to understand the systems that we are affecting,
• 4:26
  Speaker 1: that we are influencing. When we say, oh, the oceans
• 4:29
  Speaker 1: are basically infinite, it's okay to throw plastic in them.
• 4:32
  Speaker 1: It's important that we understand the water cycle and how
• 4:34
  Speaker 1: that actually works, and so questions about the nature of
• 4:37
  Speaker 1: our home are very important as well as just feeding
• 4:41
  Speaker 1: our curiosity for how everything came together to create the
• 4:44
  Speaker 1: conditions that allow for us to exist. It feels so
• 4:48
  Speaker 1: much like it was made for us. I love this
• 4:51
  Speaker 1: quote from I think it was Douglas Adams, who wrote
• 4:55
  Speaker 1: The Hitchhiker's Guide to the Galaxy series, who talked about
• 4:58
  Speaker 1: how when you have a ditch in the road, the
• 5:01
  Speaker 1: puddle of water that forms, and it thinks, Wow, how
• 5:04
  Speaker 1: convenient that this ditch was made just for me, And
• 5:08
  Speaker 1: maybe that's how we feel about the Earth. It was
• 5:11
  Speaker 1: made just for us. In fact, we were made just
• 5:15
  Speaker 1: for the Earth. But speaking of water, that is one
• 5:18
  Speaker 1: of my favorite things about the planet Earth, how much
• 5:21
  Speaker 1: water there is. As a living organism. I certainly enjoy
• 5:26
  Speaker 1: that aspect to life on this planet. One of my
• 5:29
  Speaker 1: favorite things about studies of the Earth is just how
• 5:32
  Speaker 1: much those stories have changed over the years, how many
• 5:36
  Speaker 1: mind blowing ideas we have unearthed in our studies. You know,
• 5:40
  Speaker 1: the picture of how the Earth is formed shows that
• 5:43
  Speaker 1: it's not just like a planet that's been zipping around
• 5:45
  Speaker 1: the Sun for the last few billion years, but that
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  Speaker 1: there is crazy chaos involved. You know that there might
• 5:51
  Speaker 1: have been a huge mar size impact or which helped
• 5:54
  Speaker 1: to form the Moon. The Earth might have been very
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  Speaker 1: different early on, and really basic questions about what's going
• 6:00
  Speaker 1: on inside it, how it's magnetic field works, and where
• 6:03
  Speaker 1: all the stuff that made it came from. These questions
• 6:05
  Speaker 1: are still unanswered, which means that there might be exciting
• 6:09
  Speaker 1: discoveries still ahead. We might change dramatically our whole concept
• 6:14
  Speaker 1: of like what the Earth is, just by asking pretty
• 6:17
  Speaker 1: basic questions about what's in it and you put your
• 6:20
  Speaker 1: finger on a juicy one literally, because one of the
• 6:24
  Speaker 1: important features of Earth, of course, is it's water. I mean,
• 6:27
  Speaker 1: if you looked at Earth from outer space, you would say, oh,
• 6:31
  Speaker 1: the Earth is a water planet. We mostly walk around
• 6:33
  Speaker 1: on the surface, so we think of like you know,
• 6:35
  Speaker 1: the continents as the sort of main part of the Earth,
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  Speaker 1: but really if you look at it from space, it's
• 6:40
  Speaker 1: mostly water. Yeah, And that's so interesting. We feel so
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  Speaker 1: our world is so restricted to the land because we
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  Speaker 1: are terrestrial organisms, but so much of life and so
• 6:53
  Speaker 1: much of the world is in the water, which is
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  Speaker 1: particularly hard for us to study, as of course terrestrial creatures.
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  Speaker 1: We can't just dive in there with our bare, flimsy
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  Speaker 1: human bodies and air breathing lungs, and so it's this vast,
• 7:10
  Speaker 1: vast area of mystery. But it's also full of life
• 7:14
  Speaker 1: and physics and chemistry. So it's not just this void
• 7:19
  Speaker 1: space right like where we have our land masses and
• 7:23
  Speaker 1: just this blue nothingness in between them. It's full of
• 7:26
  Speaker 1: stuff that is so interesting to explore. And discover and
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  Speaker 1: so much is left unknown about it, like you were
• 7:32
  Speaker 1: saying earlier, and it's another lesson about how to avoid
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  Speaker 1: being biased by your point of view. We do this
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  Speaker 1: thing over and over as scientists, where we study like
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  Speaker 1: our little ditch, as you say, and we imagine we
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  Speaker 1: generalize from that that maybe everything is just like this,
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  Speaker 1: and then we discover, oh, our ditch is actually weird
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  Speaker 1: or unusual, you know, the way that we've learned recently
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  Speaker 1: that our kind of matter is very strange in the universe.
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  Speaker 1: It's a tiny fraction of the kinds of matter that
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  Speaker 1: are out there. You can't generalize from the way our
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  Speaker 1: particles work to the way the whole universe works. In
• 8:01
  Speaker 1: that same way, we can't generalize from like how a
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  Speaker 1: life on the surface on the dry ground works to
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  Speaker 1: how life in general works. Is as you say, most
• 8:09
  Speaker 1: of it's in the ocean, And so today we'll be
• 8:11
  Speaker 1: exploring that question what is going on with the water
• 8:15
  Speaker 1: on Earth? And more specifically, on today's podcast, we'll be
• 8:18
  Speaker 1: asking the question where is most of Earth's water? If
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  Speaker 1: you look at it from space, of course you imagine, wow,
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  Speaker 1: it's mostly in the oceans. But is that the whole story.
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  Speaker 1: I am so interested to find out. It makes me
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  Speaker 1: feel like Earth is one big Easter egg and inside
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  Speaker 1: is maybe chocolate or maybe water. Yeah. Absolutely, And if
• 8:43
  Speaker 1: you talk to geologists, it turns out that water is
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  Speaker 1: important not just for life and for cocktails, but also
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  Speaker 1: for important geological processes. It allows for volcanoes, or for
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  Speaker 1: mantle flow and plate tectonics. And there's a lot more
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  Speaker 1: going on inside the Earth than you might have a imagined.
• 9:00
  Speaker 1: And that makes it sound like Earth is constantly moving
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  Speaker 1: under our feet. The Earth basically is a cosmic cocktail,
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  Speaker 1: and we are just finding out the recipe. So I
• 9:10
  Speaker 1: was wondering how much people knew about the mysteries of
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  Speaker 1: Earth's water, where it came from, and where it is
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  Speaker 1: right now. So I went out into the Internet to
• 9:19
  Speaker 1: ask our volunteers this question, where is most of the
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  Speaker 1: water on Earth? If you'd like to participate for a
• 9:26
  Speaker 1: future episode, please don't be shy, right to me two
• 9:28
  Speaker 1: questions at Daniel and Jorge dot com and I'll shoot
• 9:31
  Speaker 1: you email instructions with how to play at home. But
• 9:34
  Speaker 1: if you're listening at home today, before you hear these answers,
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  Speaker 1: ask yourself, where do you think most of the Earth's
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  Speaker 1: water is Here's what people had to say. Shouldn't you
• 9:45
  Speaker 1: understood the question correctly? The most water on Earth, it's uh,
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  Speaker 1: we have it in in the oceans. Where is it from?
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  Speaker 1: That's fro a different salvage. I think most of the
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  Speaker 1: water is in liquid form, specifically the Pacific Ocean. Have
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  Speaker 1: a hard time believing there's more water, uh, in solid
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  Speaker 1: form in Antarctica or the North Pole, or in any
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  Speaker 1: form of water vapor in the air. My first case
• 10:21
  Speaker 1: is the poles, the pole cats and the poles. And
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  Speaker 1: maybe it's a trick questions. I might say in the atmosphere,
• 10:32
  Speaker 1: I'm pretty sure it's right around the area of the
• 10:35
  Speaker 1: Mariana Trench. And do you think where it's deepest. I
• 10:42
  Speaker 1: would probably have to say in the Earth's crust, because
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  Speaker 1: I know water seeps down in there. But I remember
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  Speaker 1: hearing at one point that it was a different consistency
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  Speaker 1: or different chemical structure, but still water. I'm gonna take
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  Speaker 1: a step at this and say it's not actually on Earth,
• 11:01
  Speaker 1: it's actually in the Earth's crust. This is a tricky one.
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  Speaker 1: Of course, I would say the ocean, But then why
• 11:08
  Speaker 1: would we be asking this question. So I'm guessing that
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  Speaker 1: it's trapped in like the atmosphere in particles, in particle form,
• 11:16
  Speaker 1: I would assume it's in Antarctica, like in the polar
• 11:19
  Speaker 1: ice caps. And that's why we're so worried about global warming,
• 11:22
  Speaker 1: because the sea levels would rise in the temperature would
• 11:27
  Speaker 1: rise as well. Um, So yeah, I'm gonna say it's
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  Speaker 1: in those giant mountains of ice, basically like a continent
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  Speaker 1: of frozen water. Most of the water in the in
• 11:37
  Speaker 1: the in the on Earth should be in the Pacific
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  Speaker 1: Ocean because it's the biggest ocean, and also because you
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  Speaker 1: have like the Myra and Mariana Trench, which is like
• 11:46
  Speaker 1: ten thousand, ten thousand meters deep. I believe most of
• 11:51
  Speaker 1: the water on Earth are underground, somewhere in between the
• 11:57
  Speaker 1: surface and the center of work. All the all the
• 12:00
  Speaker 1: oceans are once we see most and we we have
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  Speaker 1: more access to they are just like a thing, a
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  Speaker 1: layer of our planet. They are really really tiny compared
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  Speaker 1: to the diameter of Earth. The obvious answer is the oceans,
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  Speaker 1: but that's probably too obvious. I'm guessing it's wrong if
• 12:23
  Speaker 1: you're talking about freshwater. I did some work a while
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  Speaker 1: ago on modeling the glaciers in Antarctica and Greenland, so
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  Speaker 1: I'd say the ice sheets there have the largest amount
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  Speaker 1: of freshwater, and even more if you include the Arctic
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  Speaker 1: ice Cap and the rest of the glaciers around the world.
• 12:42
  Speaker 1: I think the obvious answer is in the oceans, but
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  Speaker 1: I suspect that's not correct. I think most of the
• 12:49
  Speaker 1: water on on our planet is in the crust, so
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  Speaker 1: it's in the plates of the crust, and maybe a
• 12:56
  Speaker 1: little bit deeper as well, So I think that's where
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  Speaker 1: the vast majority waters um in the in area, not
• 13:02
  Speaker 1: in the atmosphere or the oceans. All right, Katie, what
• 13:04
  Speaker 1: do you think of these answers? I mean, that's really interesting,
• 13:07
  Speaker 1: much more creative than my brain would go like, because
• 13:11
  Speaker 1: I think, of course oceans, lots of water in the oceans.
• 13:15
  Speaker 1: But yeah, I do like this idea that maybe there's
• 13:18
  Speaker 1: some secret water tucked away deep inside the Earth, because
• 13:23
  Speaker 1: when you think about it, you know, we can't there's
• 13:26
  Speaker 1: so much of the planet at this point in our
• 13:29
  Speaker 1: state of technology we cannot explore without being very much
• 13:34
  Speaker 1: melted or crushed. Yeah, that's absolutely true. There are mysteries
• 13:37
  Speaker 1: deep in the Earth. I really like that the listeners
• 13:40
  Speaker 1: point out the variety of different kinds of water just
• 13:43
  Speaker 1: here on the surface. Obviously you've got your oceans, but
• 13:46
  Speaker 1: then there's water in the atmosphere. There's the polar ice caps,
• 13:49
  Speaker 1: there's lakes and rivers. There's so many different kinds of
• 13:52
  Speaker 1: water just here on the surface with us. And like
• 13:55
  Speaker 1: how some folks were wondering, like how much water could
• 13:58
  Speaker 1: be in the atmosphere, how much water could be in
• 14:01
  Speaker 1: the polarized caps. Yeah, because water so versatile. It comes
• 14:05
  Speaker 1: in a solid, a liquid, and a gas, so there's
• 14:10
  Speaker 1: much more opportunity for it to exist than just in
• 14:14
  Speaker 1: you know, the big old puddle of the ocean. And
• 14:17
  Speaker 1: one of my favorite things about geology of water is
• 14:20
  Speaker 1: that geologists talk about water in a crazy unit. They
• 14:23
  Speaker 1: use a unit of oceans, Like how many oceans of
• 14:27
  Speaker 1: water are we talking about? So one ocean of water
• 14:31
  Speaker 1: is basically all the water on the surface of the Earth,
• 14:34
  Speaker 1: And if you had like five oceans, that's like five
• 14:37
  Speaker 1: times all the water on the surface. It's a crazy unit.
• 14:41
  Speaker 1: I love when people invent insane units because they're just
• 14:43
  Speaker 1: talking about vast quantities of stuff. You know, now, how
• 14:47
  Speaker 1: many Olympic swimming pools. Would an ocean be some very
• 14:53
  Speaker 1: big number, more cocktails than you could drink in an
• 14:56
  Speaker 1: evening with aliens, that's for sure. I love of water.
• 15:00
  Speaker 1: I like to drink it. Uh, it is good for
• 15:03
  Speaker 1: my body to be alive. But has it all it
• 15:07
  Speaker 1: seems so convenient for life. How did it even get here?
• 15:12
  Speaker 1: How did we even get water on the planet Earth.
• 15:15
  Speaker 1: It's a really fascinating question. It turns out to be
• 15:17
  Speaker 1: a really important one to understand where the water is,
• 15:22
  Speaker 1: is to figure out where it came from, how it
• 15:25
  Speaker 1: formed with the Earth, or whether it formed with the Earth.
• 15:28
  Speaker 1: So these are all really interesting, interconnected questions. And this
• 15:32
  Speaker 1: sort of a standard story you hear in science and
• 15:34
  Speaker 1: we've talked about on the podcast. It turns out to
• 15:37
  Speaker 1: be a little bit more complex. Recent studies have sort
• 15:40
  Speaker 1: of cracked open some questions about that. But the standard tale,
• 15:43
  Speaker 1: the one we begin with, it goes all the way
• 15:45
  Speaker 1: back to the origins of the Solar System, so you know,
• 15:48
  Speaker 1: the Sun and the planets didn't exist throughout the whole
• 15:51
  Speaker 1: history of the universe. The universe existed for like nine
• 15:54
  Speaker 1: billion years before our Solar system came together, before our
• 15:57
  Speaker 1: star even shined, which is sort of hard to imagine. Again,
• 16:01
  Speaker 1: we think about like our little ditch as the most
• 16:03
  Speaker 1: important place in the universe, But almost ten billion years
• 16:06
  Speaker 1: went on before our ditch was even form. But our
• 16:09
  Speaker 1: solar system came together from a huge cloud of gas
• 16:12
  Speaker 1: and dust, and lots of those bits were left over
• 16:14
  Speaker 1: from other stars that lived and then blew up and
• 16:17
  Speaker 1: spread their materials out into the universe. We're kind of
• 16:20
  Speaker 1: a recycled solar system. You know, at the end of
• 16:24
  Speaker 1: the night, you take all the half drunk cocktails from
• 16:27
  Speaker 1: the bar, you pour them all together, make a mix.
• 16:29
  Speaker 1: That's basically our solar system. That is called a brain
• 16:33
  Speaker 1: smash or not a cosmic cocktail. Well, you mix all
• 16:38
  Speaker 1: that stuff together, and you know, you have a lot
• 16:41
  Speaker 1: of hydrogen. Most of it is hydrogen because that's just
• 16:44
  Speaker 1: what the universe started with after the Big Bang. But
• 16:46
  Speaker 1: you have bits of oxygen and carbon and heavier stuff
• 16:49
  Speaker 1: in their uranium from neutron star collisions, etcetera. And then
• 16:53
  Speaker 1: something triggers a collapse. The cloud gets cold enough and
• 16:56
  Speaker 1: maybe there's a super and over shock wave that comes by,
• 16:58
  Speaker 1: and you start to get a gravitational elapse and things
• 17:00
  Speaker 1: start to condense. Most of the stuff, of course, goes
• 17:03
  Speaker 1: to the Sun. The hygrogen gets pulled in, and then
• 17:05
  Speaker 1: you get the formations of this planetary disk, which becomes
• 17:08
  Speaker 1: all of the planets. And again a lot of it
• 17:10
  Speaker 1: goes to Jupiter, but some of it pulls together and
• 17:13
  Speaker 1: forms like the inner rocky planets. But then it's fascinating
• 17:17
  Speaker 1: because you get different compositions of stuff further out and
• 17:21
  Speaker 1: closer into the Sun. Like closer into the Sun, of
• 17:24
  Speaker 1: course it's warmer. You've got lots of solar radiation, so
• 17:27
  Speaker 1: things like water, for example, can't exist in solid form
• 17:31
  Speaker 1: in the inner Solar System. You've got like molecules of water.
• 17:34
  Speaker 1: They get blown out to the outer Solar System because
• 17:36
  Speaker 1: their vapor, whereas in the outer Solar System water can
• 17:40
  Speaker 1: freeze so it can participate in like you know, gravitational accumulation.
• 17:44
  Speaker 1: That's why you get like ice planets. Further out in
• 17:46
  Speaker 1: the Solar System, you don't get ice planets like near
• 17:49
  Speaker 1: Mercury and Venus. And it's so nice that we happened
• 17:52
  Speaker 1: to be right in the middle there where we're not
• 17:55
  Speaker 1: an ice planet, but we're also not just avoid of
• 17:58
  Speaker 1: any water. Otherwise we couldn't be here yeah, that's true.
• 18:02
  Speaker 1: Although we think that the young Earth was probably born
• 18:05
  Speaker 1: dry because the conditions were not good for water to
• 18:07
  Speaker 1: be liquid on the surface. It would just to get
• 18:09
  Speaker 1: vaporized and then it would sort of float away and
• 18:12
  Speaker 1: get blown out into the rest of the Solar System.
• 18:14
  Speaker 1: And so they think that like, while there may have
• 18:16
  Speaker 1: been water as part of the formation of the Earth,
• 18:20
  Speaker 1: any of it that existed on the surface probably got
• 18:23
  Speaker 1: blown away, got blasted clean very early on in the
• 18:26
  Speaker 1: Solar System's history. So that is very different from the
• 18:29
  Speaker 1: ocean filled planet that I know of in terms of like,
• 18:34
  Speaker 1: you know, the early oceans just being these huge chaotic
• 18:39
  Speaker 1: masses of water and chemicals with some land around. But
• 18:44
  Speaker 1: how did we get from being just a dried out,
• 18:47
  Speaker 1: desiccated planet to being one that is so full of
• 18:50
  Speaker 1: these huge oceans. It's a question that people are still exploring.
• 18:54
  Speaker 1: But one of the ideas is that after the chaos
• 18:57
  Speaker 1: of the Earth's formation and the drying out actually of
• 19:00
  Speaker 1: the Earth's surface and then the Moon forming collision, right
• 19:03
  Speaker 1: where some huge object comes and smashes like vaporizes the
• 19:08
  Speaker 1: entire crust and forms the Earth and the Moon, you know,
• 19:10
  Speaker 1: oceans could never have survived any of that. But they
• 19:13
  Speaker 1: think that after all of that initial chaos, water came
• 19:16
  Speaker 1: back to the Earth. You know, the initial water that
• 19:19
  Speaker 1: would have formed primordial oceans is gone, but that water
• 19:22
  Speaker 1: was redelivered to the surface by icy messengers. And so
• 19:26
  Speaker 1: sometimes people say it might be comets, because comets are
• 19:29
  Speaker 1: basically snowballs, and you land enough comets on the surface
• 19:32
  Speaker 1: of the Earth to basically fill an ocean. Some people
• 19:36
  Speaker 1: think it might be more like asteroids, that asteroids have
• 19:39
  Speaker 1: a lot of water in them as well, essentially the
• 19:41
  Speaker 1: form of ice, and that these carbonaceous chondrites they're called
• 19:44
  Speaker 1: might have the right mix of the special kind of
• 19:46
  Speaker 1: water to basically replenish Earth with one ocean, like deliver
• 19:51
  Speaker 1: an ocean of water to Earth. That's amazing. I love
• 19:54
  Speaker 1: the idea that little baby Earth just got pummeled with
• 19:57
  Speaker 1: enough snowballs that oceans started a form. It's crazy to
• 20:01
  Speaker 1: imagine that you could deliver an entire ocean. I mean,
• 20:04
  Speaker 1: the quantities of water in the ocean are just incredible.
• 20:07
  Speaker 1: I live here in southern California. We go out to
• 20:10
  Speaker 1: the beach all the time and it's just, oh my gosh,
• 20:13
  Speaker 1: it's so much water. You know, and we can hardly
• 20:15
  Speaker 1: see a tiny little slice of it. And you can
• 20:17
  Speaker 1: sail for a thousand miles and remember flying once for
• 20:20
  Speaker 1: an academic conference in Tahiti, which is quite a boondoggle,
• 20:24
  Speaker 1: but you just spend like hours and hours flying over
• 20:26
  Speaker 1: water which is like miles deep. It's really hard to
• 20:29
  Speaker 1: imagine filling that up with snowballs. Like if your job
• 20:33
  Speaker 1: was to throw snowballs at the Earth until you had
• 20:36
  Speaker 1: an ocean's worth, it feels like you'd be there forever.
• 20:38
  Speaker 1: And then when you look at some of these diagrams
• 20:41
  Speaker 1: of like the deepest points of the ocean and how
• 20:43
  Speaker 1: are you're just kind of stacking up statues of liberty.
• 20:47
  Speaker 1: There's an immensity to it that's almost intimidating, exactly. And
• 20:51
  Speaker 1: I think the way to reconcile that is to realize
• 20:53
  Speaker 1: that that immensity is actually absolutely tiny on the scales
• 20:57
  Speaker 1: that we're talking about. I mean, the ocean, you right,
• 21:00
  Speaker 1: it's vast, it's deep, it's incredible. On the other hand,
• 21:02
  Speaker 1: it's also a very very thin layer on top of
• 21:06
  Speaker 1: the Earth. So like the ocean in terms of like
• 21:08
  Speaker 1: fraction of the Earth's volume is paltry. You know, like
• 21:11
  Speaker 1: if you were holding the Earth in your hand, it
• 21:13
  Speaker 1: would like feel a little bit wet. The oceans just
• 21:17
  Speaker 1: sit as a very thin layer on top of this
• 21:19
  Speaker 1: massive Earth. And that's the clue, because there's so much
• 21:23
  Speaker 1: material out there in the Solar System that if you
• 21:25
  Speaker 1: smash a fairly large meteor or comet onto the Earth
• 21:29
  Speaker 1: and its friends could easily contribute enough water to replenish
• 21:32
  Speaker 1: this fairly thin ocean we have on our surface. So
• 21:36
  Speaker 1: it's kind of a soggy marble rather than a water balloon.
• 21:41
  Speaker 1: So is Earth is holding all this water because the
• 21:45
  Speaker 1: water is pulled in by Earth's gravity? And is it
• 21:48
  Speaker 1: protected at all from the universe? Like, why doesn't it
• 21:51
  Speaker 1: just evaporate? It does actually still evaporate. Water is fairly light,
• 21:55
  Speaker 1: and if it's in the upper atmosphere, it can get
• 21:57
  Speaker 1: blown away by the Solar wind. And the Earth is
• 22:00
  Speaker 1: constantly losing atmosphere to space all the time, and water
• 22:03
  Speaker 1: is a big part of that. And so we are
• 22:06
  Speaker 1: still losing some water and then we're getting some more
• 22:08
  Speaker 1: water as things hit the upper atmosphere. It's not like
• 22:11
  Speaker 1: the Earth is isolated from the rest of the Solar System.
• 22:13
  Speaker 1: It's part of this whole complex network. Things are moving
• 22:16
  Speaker 1: much slower than they did very early on. But you
• 22:19
  Speaker 1: know where we are today is like a snapshot of
• 22:22
  Speaker 1: a very slow moving process, sort of like when you
• 22:25
  Speaker 1: think about the continents. You know, the continents, you don't
• 22:28
  Speaker 1: think about the moving, but you know in your heart
• 22:31
  Speaker 1: that in a million years and in a hundred million years,
• 22:33
  Speaker 1: the surface of the Earth will look very different. I mean,
• 22:36
  Speaker 1: if you live in California, you probably do think about
• 22:39
  Speaker 1: the continent's moving, because it does happen. Yeah, exactly there
• 22:45
  Speaker 1: this shaken and sometimes stirred, but you know, I love
• 22:47
  Speaker 1: getting this glimpse as to these geological time scales that
• 22:51
  Speaker 1: the Earth really is changing, the solar system really is changing,
• 22:54
  Speaker 1: and that water itself is flowing around the Solar system
• 22:57
  Speaker 1: from here to there. It's super fascinating and the way
• 23:00
  Speaker 1: that they figured this stuff out is also really an
• 23:02
  Speaker 1: incredible piece of detective work. Ah, the suspense is killing me. Well,
• 23:07
  Speaker 1: I'll just drink a big glass of water while I wait.
• 23:09
  Speaker 1: Let's take a quick break, and then we'll talk about
• 23:12
  Speaker 1: how we figure out where water on Earth has come from. Okay,
• 23:29
  Speaker 1: we're back and we're talking about Earth as a cocktail.
• 23:32
  Speaker 1: It's got lots of nickel, and it's got a delicious
• 23:34
  Speaker 1: drop of cosmic sprite. You left us on a cliffhanger
• 23:38
  Speaker 1: about how we discovered where this water came from. And
• 23:41
  Speaker 1: I have to know, I've been sweating buckets and I've
• 23:44
  Speaker 1: been trying to replenish my water by drinking glasses of water.
• 23:48
  Speaker 1: Just I guess kind of like, maybe is this, what
• 23:51
  Speaker 1: is this? How we discovered it? People we're thinking about
• 23:55
  Speaker 1: how maybe Earth got its water, and then they started
• 23:57
  Speaker 1: sweating because they were thinking so much, and then drinking
• 23:59
  Speaker 1: and wedding, and then came to them all of a sudden.
• 24:02
  Speaker 1: I don't know that much about the personal history of
• 24:04
  Speaker 1: those scientists, but the scientific history of it is quite interesting.
• 24:09
  Speaker 1: It turns out that water is not the same everywhere.
• 24:12
  Speaker 1: Mostly water has an oxygen and then two hydrogen's right
• 24:15
  Speaker 1: H two O, and hydrogen is the most common element
• 24:18
  Speaker 1: in the universe. It's just a proton with an electron
• 24:20
  Speaker 1: around it, right, Well, that's the normal hydrogen, but there's
• 24:23
  Speaker 1: another form of it. You can also add a neutron.
• 24:26
  Speaker 1: So if your nucleus has a proton and a neutron
• 24:28
  Speaker 1: in it, we call that deuterium. So it's exactly the
• 24:31
  Speaker 1: same electric charge, and the properties of it are very
• 24:34
  Speaker 1: very similar. But it's a little bit heavier than normal hydrogen.
• 24:37
  Speaker 1: And so if you then form water with deuterium instead
• 24:41
  Speaker 1: of hydrogen, you get something we call heavy water. And
• 24:44
  Speaker 1: so it's got a normal hydrogen, one heavier hydrogen deuterium
• 24:48
  Speaker 1: and then oxygen, and it has very similar properties to
• 24:51
  Speaker 1: normal water. Okay, so if you're looking at a glass
• 24:54
  Speaker 1: of deuterium water versus normal water, can you really visually
• 24:59
  Speaker 1: or physical really tell a difference on a human level.
• 25:03
  Speaker 1: That's a great question. Well, heavy water is like ten
• 25:06
  Speaker 1: percent denser than normal water, so you might notice if
• 25:09
  Speaker 1: you pick it up, you're like, this feels a little
• 25:11
  Speaker 1: bit heavy. Suppose if you're like very sensitive to the
• 25:14
  Speaker 1: contents of your cocktails, But otherwise it seems sort of normal.
• 25:17
  Speaker 1: We use heavy water on Earth for various industrial things.
• 25:20
  Speaker 1: Is it drinkable? Heavy water can't participate in biological functions
• 25:24
  Speaker 1: in the same way, But if you drank it, it
• 25:26
  Speaker 1: wouldn't be that big a deal because you have to
• 25:28
  Speaker 1: replace like a very large fraction of your body's light
• 25:31
  Speaker 1: water with heavy water before became toxic. So, like you know,
• 25:35
  Speaker 1: accidental poisoning with heavy water is not something to worry about.
• 25:38
  Speaker 1: If you, like are in a lab and there's a
• 25:40
  Speaker 1: glass of heavy water and you accidentally drink it, you're
• 25:42
  Speaker 1: not going to die. Okay, that's good, So drink heavy
• 25:45
  Speaker 1: water responsibly. I wouldn't recommend drinking anything. I'm just saying
• 25:50
  Speaker 1: if you just did, don't panic. So I'm assuming like
• 25:55
  Speaker 1: you're not going to go out to a lake or
• 25:57
  Speaker 1: a stream and just find, you know, spot of heavy water.
• 26:01
  Speaker 1: Where would you find heavy water on earth? Or do
• 26:04
  Speaker 1: you have to create it? Heavy water is everywhere. All
• 26:07
  Speaker 1: the water on Earth has some heavy water in it.
• 26:10
  Speaker 1: So it's less than like one part per mill of
• 26:13
  Speaker 1: deuterium to hydrogen. So every glass of water you drink,
• 26:17
  Speaker 1: as you know, it's less than like one thousands heavy water,
• 26:20
  Speaker 1: but it's there. It's everywhere. I just spit out my water.
• 26:23
  Speaker 1: You couldn't hear it, but I did do it. Well,
• 26:26
  Speaker 1: you shouldn't reject it because you're also one part in
• 26:29
  Speaker 1: the thousand's heavy water, like you have deuterium in you. Yeah,
• 26:33
  Speaker 1: But one of the really interesting things is that this
• 26:35
  Speaker 1: fraction how much heavy water there is how much deuterium
• 26:38
  Speaker 1: there is changes depending on where you are in the
• 26:42
  Speaker 1: Solar system. So like you can use this as sort
• 26:45
  Speaker 1: of a fingerprint. If you get a glass of water,
• 26:48
  Speaker 1: you can get a clue as to where it came
• 26:49
  Speaker 1: from in the Solar system based on what fraction of
• 26:52
  Speaker 1: it is heavy water. Wow, so can we tell where
• 26:57
  Speaker 1: the Earth was hit by these visitors from the Solar
• 27:00
  Speaker 1: system based on concentration of the heavy water. Well, most
• 27:03
  Speaker 1: of the water on Earth has about all the same
• 27:06
  Speaker 1: heavy water ratio, Like all the oceans have the same
• 27:09
  Speaker 1: heavy water ratio. It's all mixed together. But what we
• 27:11
  Speaker 1: can do is say, like, where else in the Solar
• 27:13
  Speaker 1: system has this same heavy water ratio? And then we
• 27:17
  Speaker 1: can say that's probably where the water came from. And
• 27:19
  Speaker 1: it turns out that Earth's oceans have a higher fraction
• 27:22
  Speaker 1: of heavy water than you would expect to have been
• 27:25
  Speaker 1: formed in this region of the Solar system. It's more
• 27:28
  Speaker 1: like the heavy water ratio as you find further out
• 27:30
  Speaker 1: in the Solar system, like in the asteroid belt or
• 27:33
  Speaker 1: in the ort Cloud where they think there was more
• 27:35
  Speaker 1: deuterium early on. So we got our water imported from
• 27:39
  Speaker 1: the or cloud. Yes, And so that was one of
• 27:41
  Speaker 1: the clues that led to this idea that the water
• 27:44
  Speaker 1: might have come from comets and from asteroids because those
• 27:47
  Speaker 1: that they thought had this kind of heavy water. For
• 27:49
  Speaker 1: a long time, people thought, oh, it's probably commets, because
• 27:52
  Speaker 1: comets are snowballs and asteroids are are rockier. But remember
• 27:56
  Speaker 1: on our recent podcast episode we talked about comets and
• 27:59
  Speaker 1: how big they can get and how crazy they are,
• 28:01
  Speaker 1: and you asked what we had learned by recently landing
• 28:05
  Speaker 1: something on the surface of a comet. And that's actually
• 28:08
  Speaker 1: relevant to today's podcast because when they did that, when
• 28:11
  Speaker 1: they sent the Rosetta spacecraft up and they sent a
• 28:14
  Speaker 1: lander down onto the surface of the comet, one of
• 28:17
  Speaker 1: the things it did was measure the deteriorum fraction of
• 28:20
  Speaker 1: the water in that commet, to ask like, is it
• 28:22
  Speaker 1: the same as the heavy water fraction here on Earth
• 28:25
  Speaker 1: or is it totally different? So what did we find.
• 28:27
  Speaker 1: Are we getting our water from comets or from asteroids? Well,
• 28:30
  Speaker 1: what they found is that one commet had a lot
• 28:33
  Speaker 1: of heavy water on it, more than we have here
• 28:35
  Speaker 1: on Earth, like a higher fraction. So then people, oh,
• 28:39
  Speaker 1: maybe comets didn't contribute that much to Earth's water. Maybe
• 28:42
  Speaker 1: it was more asteroids because asteroids that they've sampled have
• 28:45
  Speaker 1: a heavy water fraction that's more similar to Earth. But
• 28:48
  Speaker 1: the picture is sort of confusing because then they sampled
• 28:50
  Speaker 1: from another comet and they found a fraction that is
• 28:53
  Speaker 1: more similar to Earth. So the story is like, wow,
• 28:55
  Speaker 1: those comments are a mixed bunches. You can't just say, like,
• 28:58
  Speaker 1: all the comets in the cloud have one heavy water fraction,
• 29:02
  Speaker 1: some of them have a lot, some of them don't
• 29:03
  Speaker 1: have very much at all. It's really an evolving story
• 29:06
  Speaker 1: right now. It's not something we understand very well. You
• 29:09
  Speaker 1: can't judge a comment by a single surface lander, as
• 29:13
  Speaker 1: the old A Dodge goes, Yeah, We'll remember, the Orc
• 29:15
  Speaker 1: Cloud has trillions of objects in it, so you can't
• 29:17
  Speaker 1: just like pick one and say this one is like
• 29:20
  Speaker 1: all the rest of them. Right now, we've like sampled
• 29:21
  Speaker 1: two of these things and we get two different pictures.
• 29:24
  Speaker 1: That suggests that there's a lot of crazy stuff going
• 29:26
  Speaker 1: on there in the Orc Cloud. So we got our
• 29:29
  Speaker 1: water imported from the Orc Cloud, which it makes me
• 29:32
  Speaker 1: feel like a fancy planet, like, yes, this is water
• 29:35
  Speaker 1: imported from the Orc Cloud. If your career as a
• 29:39
  Speaker 1: scientist doesn't work out, I think you should start marketing
• 29:43
  Speaker 1: water as Orc water I imported from the Orc Cloud
• 29:47
  Speaker 1: and make a killing that's even fancier than Fiji water.
• 29:50
  Speaker 1: It's like, Wow, I've protet is from the Orc Cloud.
• 29:53
  Speaker 1: That's awesome. And to be totally clear, I think the
• 29:55
  Speaker 1: sort of leading scientific hypothesis right now is that comments
• 29:59
  Speaker 1: did contruy me to the water on Earth, but not
• 30:02
  Speaker 1: all of it, maybe ten to twenty percent, and people
• 30:05
  Speaker 1: think the rest of it probably came from asteroids. There's
• 30:08
  Speaker 1: this one really big asteroid Vesta, which is the largest
• 30:11
  Speaker 1: in the Belt, and they found chunks of it on
• 30:13
  Speaker 1: Earth like it's been involved in collisions and bits broke
• 30:16
  Speaker 1: off and then fell to Earth, and they've cracked those
• 30:19
  Speaker 1: open and found water inside them, like samples of water
• 30:23
  Speaker 1: from other places in the Solar System that have agreed
• 30:25
  Speaker 1: with the heavy water fraction here on Earth. So I
• 30:27
  Speaker 1: think the leading theory right now is that comments played
• 30:30
  Speaker 1: a role, but that asteroids probably brought the bulk of
• 30:33
  Speaker 1: the water to Earth. But you know, it's an open
• 30:35
  Speaker 1: question and it's evolving, and we may have a different
• 30:37
  Speaker 1: picture in ten years. It is an actual water cocktail,
• 30:41
  Speaker 1: which sounds very boring but actually seems very fascinating. We
• 30:45
  Speaker 1: got this water now, and it seems like it's all
• 30:50
  Speaker 1: on the surface, like we're, you know, a wet marble,
• 30:53
  Speaker 1: not a water balloon. But is that really true, Like
• 30:56
  Speaker 1: is there some hidden pockets of water somewhere that we
• 31:00
  Speaker 1: don't know about. It's a great question, and it turns
• 31:02
  Speaker 1: out that there might be water deep in the Earth.
• 31:04
  Speaker 1: But first I thought it'd be fun to talk about
• 31:06
  Speaker 1: where the water is on the surface, because a lot
• 31:09
  Speaker 1: of our listeners were guessing it's like, maybe it's in
• 31:11
  Speaker 1: the atmosphere, maybe it's in the polar ice caps. And
• 31:14
  Speaker 1: some of these numbers, when I looked them up, they
• 31:15
  Speaker 1: surprised me a little bit. I mean, of course, the
• 31:18
  Speaker 1: surface of the Earth is water, and on the surface,
• 31:21
  Speaker 1: of course, most of that is the oceans. So if
• 31:23
  Speaker 1: you look at like the breakdown of where water is
• 31:26
  Speaker 1: on Earth, seven percent of all the water on the
• 31:29
  Speaker 1: surface of the Earth, so we're talking about like one
• 31:32
  Speaker 1: unit of water one ocean of water on the surface
• 31:36
  Speaker 1: of that is in the literal oceans, with almost half
• 31:39
  Speaker 1: of all the surface water on Earth being in the Pacific,
• 31:42
  Speaker 1: Like the Pacific is like half the budget all the
• 31:45
  Speaker 1: surface water on Earth. It's incredible. I'd love to be
• 31:48
  Speaker 1: at that board meeting of early Earth, like where should
• 31:51
  Speaker 1: we allocate all this water? Exactly? It's like it's the
• 31:55
  Speaker 1: biggest cocktail on the planet. And that's right. So already
• 31:59
  Speaker 1: now you're talking about just three of the Earth. Water
• 32:02
  Speaker 1: gets broken up into things like snow and glaciers. You know,
• 32:06
  Speaker 1: like a percent and a half is snow and glaciers,
• 32:09
  Speaker 1: and most of that is in Antarctica. Like Antarctica by
• 32:13
  Speaker 1: itself is more than a percent of all the water
• 32:16
  Speaker 1: on Earth. That's kind of incredible. Yeah, yeah, I mean
• 32:19
  Speaker 1: it may not seem like a lot, but one point
• 32:24
  Speaker 1: five percent of all of the water on the surface,
• 32:28
  Speaker 1: that's a huge amount of water. And that reminds me
• 32:31
  Speaker 1: of one of the listeners answers was thinking, maybe a
• 32:34
  Speaker 1: lot of the water are in these ice caps because
• 32:38
  Speaker 1: we're very concerned about them with global warming, But it
• 32:40
  Speaker 1: really doesn't take that like proportionally, it doesn't take that
• 32:44
  Speaker 1: much water to cause sea levels to rise. And so
• 32:48
  Speaker 1: even if this is just one point five percent of
• 32:52
  Speaker 1: the total water, that's huge, huge amounts of water. And
• 32:56
  Speaker 1: the other missing one and a half percent and oceans
• 33:00
  Speaker 1: percent and a half basically in Antarctica and other snow
• 33:04
  Speaker 1: and glaciers. The missing percent and a half is groundwater.
• 33:08
  Speaker 1: So that's water that's underground that we can tap and
• 33:10
  Speaker 1: we can drink, and that's most of the water on Earth.
• 33:13
  Speaker 1: But you notice we haven't talked about like the atmosphere
• 33:15
  Speaker 1: and lakes and rivers, and that's because those are almost negligible.
• 33:20
  Speaker 1: Like all the water and all the lakes on the
• 33:23
  Speaker 1: surface of the Earth is point zero one percent of
• 33:27
  Speaker 1: the surface water on the Earth. Almost nothing. And I
• 33:30
  Speaker 1: mean I've seen lakes. It doesn't look like nothing to
• 33:33
  Speaker 1: me from a human perspective. No, And I've lived in
• 33:36
  Speaker 1: Chicago near Lake Michigan, which is amazing. Right in Lake Superior,
• 33:40
  Speaker 1: they're vaft. If you're in the middle of them, it
• 33:42
  Speaker 1: feels like you're on an ocean. I mean, there's waves
• 33:44
  Speaker 1: and everything in storms, and you can capsize and you
• 33:46
  Speaker 1: can die. And basically a puddle. That's zero point zero
• 33:50
  Speaker 1: one percent of the water on Earth. So you should
• 33:52
  Speaker 1: definitely take it seriously. And then as you keep going,
• 33:55
  Speaker 1: like point zero zero one percent of the water on
• 33:58
  Speaker 1: Earth is in the atmosphere and the form of vapor
• 34:00
  Speaker 1: and clouds. It's just like the tiniest tiniest fraction. Do
• 34:04
  Speaker 1: you feel vulnerable somehow? Yeah, it does. And then zero
• 34:08
  Speaker 1: point zero zero zero zero one is in rivers, right,
• 34:12
  Speaker 1: Rivers are basically irrelevant, though of course they play a
• 34:15
  Speaker 1: vital role in you know, life on Earth and in
• 34:19
  Speaker 1: salmon and all sorts of ecosystems. Yeah, you better not
• 34:22
  Speaker 1: go around talking about how rivers are negligible to beavers,
• 34:26
  Speaker 1: because they will they have sharp teeth, they're dangerous. And
• 34:30
  Speaker 1: then something I was curious about is like what about
• 34:32
  Speaker 1: the water in life? You know, there's all sorts of
• 34:35
  Speaker 1: life in water, right, there's every sample of water you take,
• 34:38
  Speaker 1: every cup of water has like zillions of microbes in it.
• 34:41
  Speaker 1: But what fraction of water on Earth is in living systems?
• 34:45
  Speaker 1: Right now? You know, all the elephants and all the
• 34:47
  Speaker 1: whales and all the microbes add them all up together,
• 34:50
  Speaker 1: and that's zero point zero zero zero zero zero eight
• 34:54
  Speaker 1: per cent of the water on Earth. So you know,
• 34:57
  Speaker 1: like that's basically negligible from the point of view of
• 35:00
  Speaker 1: like how much water there is, But of course it's
• 35:02
  Speaker 1: important to us, right, so you can't just weigh these
• 35:05
  Speaker 1: things by their fractions. Obviously. That is so incredible, I mean,
• 35:09
  Speaker 1: it really puts in perspective almost to me more importantly,
• 35:12
  Speaker 1: not like how small we are, but how massively, massively
• 35:16
  Speaker 1: huge the oceans are. It's just mind boggling. I told
• 35:20
  Speaker 1: this number to my wife, who's a biologist, and she
• 35:22
  Speaker 1: asked me, well, what fraction of water on Earth has
• 35:25
  Speaker 1: ever been in life? Like which molecules have participated in
• 35:30
  Speaker 1: you know, some microbe or some beaver somewhere. That has
• 35:33
  Speaker 1: a great question. I don't know the answer, I imagine
• 35:36
  Speaker 1: it's probably a large fraction, right, Probably every water molecule
• 35:39
  Speaker 1: has gotten to be alive at some point. Yeah, that
• 35:42
  Speaker 1: I mean, I often think about whether the water I'm
• 35:45
  Speaker 1: drinking used to be dinosaur pp often really that's like
• 35:51
  Speaker 1: a deal. Yeah, I mean, you know, if I'm I
• 35:54
  Speaker 1: put the water through my bread of filter and I'm
• 35:56
  Speaker 1: drinking it and thinking like, you know, I can purify
• 35:59
  Speaker 1: this water. But chances are this was in some kind
• 36:02
  Speaker 1: of dinosaur or maybe even in some kind of early human.
• 36:06
  Speaker 1: You know, why don't you think about maybe it used
• 36:09
  Speaker 1: to be in some early human cocktail caveman cocktail when
• 36:13
  Speaker 1: he was like, you know, fermenting something in the back
• 36:15
  Speaker 1: of the cave for a special celebration. With cave women partner.
• 36:18
  Speaker 1: You know, maybe they were making early cave juice. I
• 36:21
  Speaker 1: wonder if there's been any studies as how far back
• 36:23
  Speaker 1: people have been making alcohol. I mean, I know that
• 36:26
  Speaker 1: animals will imbibe alcohol when they come across fruit that
• 36:31
  Speaker 1: is fermenting, so probably even our primate ancestors would imbibe alcohol.
• 36:37
  Speaker 1: I would imagine we probably only started to make alcohol
• 36:40
  Speaker 1: once we started agriculture, because that's when you could actually
• 36:44
  Speaker 1: collect things like wheat and have the time to ferment it.
• 36:49
  Speaker 1: But there there is a theory that fermentation was an
• 36:52
  Speaker 1: important stage in our evolution because it can break down
• 36:57
  Speaker 1: sugars into a very nutritious and fun uh form Alright, Well,
• 37:04
  Speaker 1: probably most of the water on Earth has played a
• 37:07
  Speaker 1: rule in somebody's cocktail or in somebody's biological function, and
• 37:10
  Speaker 1: at some point in the same way that like we're
• 37:12
  Speaker 1: all breathing in part of Julius Caesar's last breath. It's
• 37:16
  Speaker 1: all a big part of the cycle, and it's all
• 37:18
  Speaker 1: mixes together. And it turns out that the water on
• 37:20
  Speaker 1: the surface of the Earth, it's only a part of
• 37:22
  Speaker 1: the water cycle of the Earth, and some of it
• 37:25
  Speaker 1: might not be on the Earth, but in the Earth.
• 37:27
  Speaker 1: So let's take another break, and when we come back,
• 37:29
  Speaker 1: we'll dive deeper into the Earth and understand whether or
• 37:32
  Speaker 1: not there is more water than just what sits on
• 37:35
  Speaker 1: the surface. All Right, we're back and we're talking about
• 37:50
  Speaker 1: where is the water on the Earth. And we've talked
• 37:53
  Speaker 1: about how most of the water that's on the surface
• 37:55
  Speaker 1: is in the Pacific Ocean, and most of that probably
• 37:58
  Speaker 1: came from distant parts of our learned neighborhood, the asteroids
• 38:01
  Speaker 1: and the comets that delivered it after the young Earth
• 38:04
  Speaker 1: had been dried out, and so that water in particular
• 38:07
  Speaker 1: and sort of a larger heavy water fraction than you
• 38:10
  Speaker 1: would expect from what would have formed in our neighborhood.
• 38:13
  Speaker 1: But of course we can look deeper than just on
• 38:16
  Speaker 1: the surface. We can drill down and ask like could
• 38:18
  Speaker 1: there be water deeper down? Drilling for water it's a
• 38:22
  Speaker 1: it's just you know, that's that's what you gotta do
• 38:26
  Speaker 1: in Texas these days. And geologists have long known that
• 38:30
  Speaker 1: there's water in the Earth's crust. Right, you drill down,
• 38:33
  Speaker 1: you drink ground water, and we know that this water
• 38:36
  Speaker 1: sort of very close to the surface, and that plays
• 38:38
  Speaker 1: an important role in like vulcanism and play tectonics, you know,
• 38:42
  Speaker 1: the way that the geology of how these things flow
• 38:44
  Speaker 1: and what pressures and temperatures depends on how much water
• 38:48
  Speaker 1: there is mixed in with them. Yeah, I mean you
• 38:50
  Speaker 1: you also see with these deep sea geothermal events that
• 38:54
  Speaker 1: are spewing, you know, these this hot, chemical filled water
• 38:59
  Speaker 1: out at the events. So even though it seems that
• 39:02
  Speaker 1: we've got all the water we need on the surface,
• 39:04
  Speaker 1: there is this constant kind of chaotic activity coming from
• 39:09
  Speaker 1: below the surface, right Yeah, And so for a long
• 39:11
  Speaker 1: time people thought, well, maybe that was the whole story.
• 39:13
  Speaker 1: You know, there's water on the surface and some of
• 39:15
  Speaker 1: it gets like forced down deeper into the crust because
• 39:18
  Speaker 1: of the crazy geology. But then people were wondering, like
• 39:22
  Speaker 1: what about even deeper? And so to remind yourself, like
• 39:26
  Speaker 1: what the sort of structure of the Earth is. We
• 39:28
  Speaker 1: have this crust which sits on top of the mantle.
• 39:31
  Speaker 1: The mantle is like rock that's not exactly liquid. It's
• 39:35
  Speaker 1: under very very high pressure, and so it can sort
• 39:37
  Speaker 1: of flow a little bit, and the crust is basically
• 39:40
  Speaker 1: floating on top of this mantle, so the upper mantle,
• 39:44
  Speaker 1: and then we have a mantle transition zone to the
• 39:47
  Speaker 1: lower mantle. And the deeper you go, the higher the
• 39:50
  Speaker 1: temperatures and the higher the pressures. Right, these things, every
• 39:53
  Speaker 1: layer has more and more stuff on top of it.
• 39:56
  Speaker 1: It's gonna be a little bit hard for people to
• 39:58
  Speaker 1: imagine sometimes, like why is there's so much pressure in
• 40:01
  Speaker 1: the center of the Earth or in the middle of
• 40:03
  Speaker 1: the Earth. And you know, imagine like diving down in
• 40:06
  Speaker 1: a swimming pool. You go really really far down in
• 40:09
  Speaker 1: the deep end, your ears start to feel the pressure.
• 40:12
  Speaker 1: That's because all all the layers of water that are
• 40:14
  Speaker 1: now on top of you, gravity is pulling them down
• 40:17
  Speaker 1: and squeezing on top of you. That's why I could
• 40:19
  Speaker 1: go like really deep in the ocean. Your submarine could
• 40:22
  Speaker 1: like implode, you could get crushed. So as you go
• 40:24
  Speaker 1: deeper deeper into the Earth, there's greater and greater pressure, right,
• 40:28
  Speaker 1: So and that pressure, that is that what is creating
• 40:31
  Speaker 1: that heat. Yeah, that's what's creating that heat. Remember that temperature.
• 40:35
  Speaker 1: A simple model for it is sort of like how
• 40:37
  Speaker 1: fast the particles are moving. So you're like a box
• 40:40
  Speaker 1: of gas. You measure it's temperature that tells you like
• 40:43
  Speaker 1: how fast the particles are zipping around and if you
• 40:46
  Speaker 1: then shrink that box, you're like pushing in on all
• 40:48
  Speaker 1: of the walls. Then basically you're adding speed to those particles.
• 40:53
  Speaker 1: Why you're adding speed is by pushing in on those sides.
• 40:56
  Speaker 1: So if the particle is going to like bounce off
• 40:58
  Speaker 1: the walls of that box, now the box instead of
• 41:00
  Speaker 1: just being like a flat wall, it's like a train
• 41:03
  Speaker 1: moving in towards the center. Bounce a tennis ball off
• 41:06
  Speaker 1: of the train, it's going to come back at you faster.
• 41:08
  Speaker 1: So you take a box of particles and you squeeze
• 41:10
  Speaker 1: it with pressure, then you're speeding up all those particles,
• 41:13
  Speaker 1: and that leads to the increased temperature. The same thing
• 41:16
  Speaker 1: is happening inside the Earth. All these layers of stuff
• 41:19
  Speaker 1: above you are squeezing down on you. That effectively heats
• 41:22
  Speaker 1: up everything. So that's why the center of the Earth
• 41:24
  Speaker 1: is hot. That plus a bunch of like radioactive decay
• 41:27
  Speaker 1: that's still happening inside the Earth that provides more temperature
• 41:30
  Speaker 1: to heat things up just offhandedly. Oh and also radioactive decay.
• 41:35
  Speaker 1: But you know, I mean that reminds me of like
• 41:37
  Speaker 1: if you've ever played ping pong ball and you have
• 41:39
  Speaker 1: a paddle and you have the ping pong ball, as
• 41:42
  Speaker 1: if you you're bouncing the ball on the table. As
• 41:44
  Speaker 1: you bring the paddle down against the ball, the bouncing
• 41:47
  Speaker 1: starts to increase in speed, in frequency. Exactly, it's exactly
• 41:52
  Speaker 1: the same thing. The whole earth is basically a big
• 41:54
  Speaker 1: ping pong paddle on all of these ping pong balls,
• 41:57
  Speaker 1: and near the center it's very very high. You know,
• 42:00
  Speaker 1: we're talking about like five thousand, six thousand degrees kelvin
• 42:04
  Speaker 1: in the very core um and you know the transition
• 42:07
  Speaker 1: region is like two thousand degrees kelvin, And so as
• 42:10
  Speaker 1: you get closer towards the center, it gets hotter and hotter.
• 42:13
  Speaker 1: So you have the mantle, and then you have a core,
• 42:15
  Speaker 1: and you've got a bunch of layers. You've got upper mantle, mantle,
• 42:17
  Speaker 1: transition zone, lower mantle, outer core, and then inner core.
• 42:21
  Speaker 1: So you're like five major regions, and people have been
• 42:24
  Speaker 1: setting like what kind of things form in those regions,
• 42:26
  Speaker 1: Like when you have this very high pressure in these
• 42:29
  Speaker 1: very high temperature and the sort of ingredients that we
• 42:32
  Speaker 1: think make up the core, you know, the silicas and
• 42:34
  Speaker 1: the nickel and the iron, what kind of things happen?
• 42:38
  Speaker 1: And so in the upper mantle sort of like the
• 42:39
  Speaker 1: layer just below the crust, it tends to form this
• 42:43
  Speaker 1: mineral they call olivine, which is basically, under these temperatures
• 42:47
  Speaker 1: and pressures, you take those ingredients to squeeze them together,
• 42:50
  Speaker 1: you get this certain chemical structure that likes to form
• 42:52
  Speaker 1: called olivine, which sounds to me like sort of like
• 42:55
  Speaker 1: a tasty Italian snack, but they tell me it's not
• 42:58
  Speaker 1: very good. I was gonna say that would be a
• 43:02
  Speaker 1: very popular concept. And here in Italy if the center
• 43:05
  Speaker 1: of the world was filled with olive oil, which is delicious,
• 43:09
  Speaker 1: this does not sound so delicious. So so olivine is
• 43:13
  Speaker 1: like this under high pressure material exactly. And the interesting
• 43:17
  Speaker 1: thing about the structure of olivine is it really cannot
• 43:20
  Speaker 1: hold water, Like the hydrogens and the oxygen's don't form
• 43:23
  Speaker 1: as part of olivine like you form alivin. It like
• 43:26
  Speaker 1: expels any water. So they think that probably the upper
• 43:29
  Speaker 1: mantle is pretty dry. There might be some water in there,
• 43:33
  Speaker 1: but it's like, you know, a hundred or two hundred
• 43:35
  Speaker 1: parts per million. So you know, as they're asking these
• 43:38
  Speaker 1: questions like where is the water on Earth, the first
• 43:40
  Speaker 1: question to ask is like, could there be water. Do
• 43:42
  Speaker 1: the temperatures and pressures and the things down there can
• 43:45
  Speaker 1: they hold water? And so for the upper mantle the
• 43:48
  Speaker 1: answer probably no. But fascinatingly, if you go deeper into
• 43:52
  Speaker 1: the mantle transition region, then this olivine turns into something else.
• 43:57
  Speaker 1: This becomes under the higher temperatures and the higher pressures,
• 44:00
  Speaker 1: becomes something called wadsleyite. And I have no idea who's
• 44:04
  Speaker 1: responsible for these names. They're totally bonkers. Could you just
• 44:07
  Speaker 1: repeat that again. It's Wadsleyite, Wadsleyite, haads leite, which does
• 44:12
  Speaker 1: not sound like something I would order on the menu
• 44:14
  Speaker 1: of an Italian restaurant. You know, I'd be like, no,
• 44:17
  Speaker 1: thank you. It sounds like it was discovered by someone
• 44:21
  Speaker 1: named Wadsley and they were like, I'm going to call
• 44:24
  Speaker 1: this wadsleyite. And you know, it's hard to imagine what
• 44:27
  Speaker 1: these things are like. It's not like we're just heating
• 44:30
  Speaker 1: something up on like you heat something up on your
• 44:33
  Speaker 1: stove and it melts, you know. He we're talking about
• 44:36
  Speaker 1: increasing the pressures of the temperatures too, really crazy amounts.
• 44:39
  Speaker 1: You know, in a transition region, we're talking about like
• 44:41
  Speaker 1: two thousand pounds per square inch of pressure. You take
• 44:45
  Speaker 1: a rock and you squeeze it that much, it's going
• 44:47
  Speaker 1: to cause it to flow. It's not necessarily melting. It's
• 44:50
  Speaker 1: still technically a solid, but it's under such pressure that
• 44:53
  Speaker 1: it can flow, it can be soft. It's sort of
• 44:56
  Speaker 1: like hot unmelted wax. That is so hard to imagine
• 45:01
  Speaker 1: something like rock in a liquid ish state. But it
• 45:07
  Speaker 1: is not melted, and it's not a liquid. That's so weird.
• 45:11
  Speaker 1: It's really weird. And one of the fascinating things about
• 45:13
  Speaker 1: it is that this chemical structure is different from olivine,
• 45:17
  Speaker 1: and it has little spaces in it, little like gaps
• 45:20
  Speaker 1: where hydrogen and oxygen can slip in. So when they
• 45:23
  Speaker 1: reproduce this stuff in the laboratory, they take like the
• 45:26
  Speaker 1: same materials and they squeeze it down into crazy temperatures
• 45:29
  Speaker 1: and pressures. They find that it can hold like one
• 45:32
  Speaker 1: to three percent of its weight in water. You like
• 45:34
  Speaker 1: take the ingredients and you squeeze them down, the water
• 45:37
  Speaker 1: like disappears into the rock. It's crazy. It's like sort
• 45:40
  Speaker 1: of like a sponge. Well, so it's like so those
• 45:43
  Speaker 1: water molecules just get all integrated in with the rock,
• 45:49
  Speaker 1: in with the rock, and so you have wadsleyite in
• 45:52
  Speaker 1: this transition region, and if you go deeper into the
• 45:54
  Speaker 1: lower mantle, it becomes something called ringwoodite, which you know,
• 45:59
  Speaker 1: sounds like a condition and you definitely don't want to
• 46:01
  Speaker 1: be died. But this stuff can also hold water, and
• 46:04
  Speaker 1: so the transition to zone, this Wesley I could have
• 46:07
  Speaker 1: like twenty thousand parts per million of water, and ringwoodite
• 46:11
  Speaker 1: in the lower mantle can have like two thousand parts
• 46:14
  Speaker 1: per million. But the lower mantle is huge, like the
• 46:16
  Speaker 1: volume is enormous. So if you add up like all
• 46:19
  Speaker 1: of the capacity of this, they think that the mantle
• 46:22
  Speaker 1: could hold like five to ten oceans of water. Oh
• 46:25
  Speaker 1: my god, that's incredible. So it would be absorbed into
• 46:31
  Speaker 1: the Wadsley I or ringwoodite, and we wouldn't necessarily see
• 46:34
  Speaker 1: this water. But if you wanted to like extract this water,
• 46:39
  Speaker 1: would you squeeze it like a sponge or would you
• 46:41
  Speaker 1: unsqueeze it like a reverse sponge? Exactly, you would unsqueeze it,
• 46:47
  Speaker 1: And so this is something called dehydration melting. It's all
• 46:51
  Speaker 1: sort of backwards because of the crazy pressures. But if
• 46:54
  Speaker 1: slabs of this stuff come up, like float up through
• 46:57
  Speaker 1: the mantle, closer to the surface with a pressure is lower,
• 47:00
  Speaker 1: and then actually melt because of the weird chemistry. Sometimes
• 47:03
  Speaker 1: you can melt something just by changing the pressure right
• 47:06
  Speaker 1: without increasing the temperature. So as the pressure decreases that
• 47:09
  Speaker 1: they melts and becomes a liquid and they produce water.
• 47:12
  Speaker 1: So you take this rock, you like, unsqueeze it and
• 47:15
  Speaker 1: it melts and produces water. Also, it's like water comes
• 47:18
  Speaker 1: out of the rock when it melts. It's really crazy
• 47:21
  Speaker 1: stuff that's really hard for me to get my mind around.
• 47:24
  Speaker 1: So it's a reverse sponge where you unsqueeze it, you
• 47:27
  Speaker 1: remove the pressure for the water to come out. Yeah, exactly,
• 47:32
  Speaker 1: And you know, so far what we're talking about is
• 47:34
  Speaker 1: like capacity for water. They've discovered that these materials that
• 47:37
  Speaker 1: are in the mantle can have water. That doesn't necessarily
• 47:40
  Speaker 1: mean that they do right, like a sponge could be dry.
• 47:42
  Speaker 1: So then the second question is like, is there actually
• 47:45
  Speaker 1: water in the mantle or is this just sort of
• 47:48
  Speaker 1: like a capacity for water. So how would we I mean,
• 47:51
  Speaker 1: can we even get that far down? I mean, if
• 47:55
  Speaker 1: it's so hot and under so much pressure, how do
• 47:58
  Speaker 1: we study the smith material Because it seems like any
• 48:02
  Speaker 1: little obviously no human can go down there. But even
• 48:05
  Speaker 1: if we had tools that could get that far down,
• 48:07
  Speaker 1: how those tools even survive? How can we study this? Yeah,
• 48:11
  Speaker 1: it's a great question, and you're right, and we can't
• 48:13
  Speaker 1: just like drill down to the center of the earth
• 48:15
  Speaker 1: and sample this stuff. But we do have a few
• 48:17
  Speaker 1: ways to study this. So number one is just like
• 48:19
  Speaker 1: proof of principle. In the laboratory. You can take these materials,
• 48:23
  Speaker 1: you can squeeze them, you can get them the whold water,
• 48:25
  Speaker 1: so you can prove like that this is possible. You
• 48:28
  Speaker 1: can put them under pressure changes, you can see the
• 48:30
  Speaker 1: water releasing. So they've been doing these studies, you know,
• 48:33
  Speaker 1: please folks at like living more National labs confirming like
• 48:36
  Speaker 1: that the chemistry is right. But then of course, how
• 48:38
  Speaker 1: do you actually see that it's there. There's a few
• 48:40
  Speaker 1: really cool ways to do it. We can't go down
• 48:42
  Speaker 1: into the earth, but one thing we can do is
• 48:44
  Speaker 1: let the earth spit up samples for us. So sometimes,
• 48:47
  Speaker 1: for example, in a volcano, you'll get like little bits
• 48:51
  Speaker 1: that come up from really really far down and have
• 48:54
  Speaker 1: survived their journey. So for example, like sometimes volcanoes will
• 48:58
  Speaker 1: spew up diamonds, diamonds that were formed very very far underground,
• 49:02
  Speaker 1: sometimes hundreds of miles under the ground, you know, hundreds
• 49:06
  Speaker 1: of kilometers under the ground. Diamonds were formed and in
• 49:09
  Speaker 1: the heart of them can be like a little sample
• 49:11
  Speaker 1: of the mantle. And because their diamond they will survive
• 49:14
  Speaker 1: the journey up other little bits of the mantle. If
• 49:17
  Speaker 1: they get spewed up from a volcano, you know, they
• 49:19
  Speaker 1: change as they come up, but a diamond will preserve
• 49:22
  Speaker 1: what's inside it. So they've actually found some of these diamonds,
• 49:25
  Speaker 1: like down in Brazil, they went digging around and they
• 49:27
  Speaker 1: found diamonds that have little bits of the mantle inside them,
• 49:31
  Speaker 1: and some of them have this like ringwoodite, and they
• 49:34
  Speaker 1: found water in them. So you can squeeze water from
• 49:39
  Speaker 1: a diamond or from I guess unsqueeze it not from
• 49:43
  Speaker 1: the diamond, but from the ringwoodite inside it. So that
• 49:46
  Speaker 1: old I guess old ancients saying had some truth to it,
• 49:51
  Speaker 1: except the opposite. So that's incredible. So it does have water.
• 49:54
  Speaker 1: We know that not only can't store water, but it
• 49:58
  Speaker 1: does have water in it. So what conclusions can we
• 50:01
  Speaker 1: draw though from such a small sample. We can't draw
• 50:05
  Speaker 1: that much from just a few diamonds that it's very exciting,
• 50:07
  Speaker 1: you know, to concretely see like actual water come out
• 50:11
  Speaker 1: of a rock from inside the earth. The better way
• 50:13
  Speaker 1: to study it to draw larger conclusions is to try
• 50:15
  Speaker 1: to do larger scale studies, and so we can sort
• 50:17
  Speaker 1: of see inside the earth without actually going there, you know,
• 50:21
  Speaker 1: one thing that we do to understand like all these
• 50:23
  Speaker 1: structures of the Earth. You might wonder like, well, how
• 50:25
  Speaker 1: do we know that there's mantle, and there's lower mental,
• 50:28
  Speaker 1: and there's core. How do we even know about any
• 50:30
  Speaker 1: of that. We know about that by sending sound waves
• 50:32
  Speaker 1: through the earth. Every time there's an earthquake that shakes
• 50:35
  Speaker 1: the earth, and those sound waves propagate through the earth.
• 50:39
  Speaker 1: And every time sound hits a barrier, you know, like
• 50:41
  Speaker 1: when sound hits glass or when sound it's water, it
• 50:45
  Speaker 1: changes direction and some of it reflects. And so by
• 50:48
  Speaker 1: listening to like the reflected sound, we can tell something
• 50:51
  Speaker 1: about the densities and the transition regions and the sort
• 50:54
  Speaker 1: of interfaces underground. So this is sort of like seismic
• 50:58
  Speaker 1: studies to tell us about what's inside the earth. So
• 51:01
  Speaker 1: we just set up a couple of speakers, put them
• 51:04
  Speaker 1: against the ground, and play some a C D C
• 51:06
  Speaker 1: and kind of listen for how it comes back up.
• 51:09
  Speaker 1: How do we actually send out and receive sound waves.
• 51:14
  Speaker 1: Do we kind of create a mechanical bat situation. We
• 51:18
  Speaker 1: can't do that, unfortunately. We can't create sounds strong enough
• 51:21
  Speaker 1: to penetrate the Earth with these studies, but the Earth
• 51:23
  Speaker 1: generates it for us. You know, there's thousands of tiny
• 51:25
  Speaker 1: earthquakes going on all the time, and these are great sources.
• 51:29
  Speaker 1: We can do the same thing. For example, on Mars,
• 51:31
  Speaker 1: they have a seismic listener on the surface of Mars
• 51:34
  Speaker 1: now listening to Mars quakes to try to understand whether
• 51:38
  Speaker 1: the core of Mars is solid or is liquid. We
• 51:41
  Speaker 1: have a whole podcast episode about that. By very carefully
• 51:44
  Speaker 1: listening to these essentially ringing of the earth like a
• 51:47
  Speaker 1: bell due to these earthquakes, they can get a sense
• 51:49
  Speaker 1: for what's going on underneath, and very specifically they listen
• 51:53
  Speaker 1: for like what's going on in these transition regions. And
• 51:56
  Speaker 1: so this ring would it if it has water in it,
• 51:59
  Speaker 1: then it can sink. It makes a little bit heavier,
• 52:02
  Speaker 1: and as it drops out of the transition zone, then
• 52:04
  Speaker 1: the pressure comes in and some of the water comes
• 52:06
  Speaker 1: out of it. Causing the mineral to melt because it
• 52:09
  Speaker 1: doesn't have the water in it anymore. And then just
• 52:12
  Speaker 1: below the transition zone where this mantle materials descending, these
• 52:15
  Speaker 1: like pools of molten minerals form, So you get like
• 52:18
  Speaker 1: different behavior at the transition regions between like the mantle
• 52:22
  Speaker 1: and the core, the different parts of the mantle, as
• 52:25
  Speaker 1: some of these things, if they have water in them,
• 52:28
  Speaker 1: rise up through it and release water as they drop
• 52:30
  Speaker 1: down through it. So all of this sort of activity
• 52:32
  Speaker 1: at the transition regions can create these like pools of
• 52:36
  Speaker 1: molten material and these will change how seismic waves propagate,
• 52:41
  Speaker 1: so they can sort of tell if water is there
• 52:43
  Speaker 1: because it changes how the seismic waves propagate, especially at
• 52:47
  Speaker 1: these transition regions. And they've done these studies and they
• 52:50
  Speaker 1: found what they think is like a massive ocean of
• 52:52
  Speaker 1: water basically deep under North America. So we think there's
• 52:58
  Speaker 1: a mass ocean of water because is I mean, from
• 53:01
  Speaker 1: what you you described, it kind of almost sounds like
• 53:03
  Speaker 1: a lava lamp where you have this material sort of
• 53:06
  Speaker 1: melting and then unmelting and then dropping down. So we're
• 53:11
  Speaker 1: measuring the water based on the pools of the molten
• 53:18
  Speaker 1: material not, and assuming that because those exist, then the
• 53:22
  Speaker 1: water must exist, right exactly, the water is necessary for
• 53:26
  Speaker 1: these minerals to have these properties that create these sort
• 53:28
  Speaker 1: of special layers that we can see with seismic bouncing.
• 53:32
  Speaker 1: That's I know, and the picture is becoming clear and clear.
• 53:35
  Speaker 1: They do these other really cool studies where they look
• 53:37
  Speaker 1: at the electrical conductivity of the earth, right, like, how
• 53:41
  Speaker 1: well does electricity propagate through the earth? You might imagine, like, well,
• 53:46
  Speaker 1: how do you do that? You just like stick you know,
• 53:48
  Speaker 1: a wire in one part of the Earth and then
• 53:50
  Speaker 1: another one and see if you can, like you know,
• 53:52
  Speaker 1: send electricity through it like your finger and shove it
• 53:56
  Speaker 1: in the dirt. Exactly. But again we have really large
• 54:00
  Speaker 1: sale questions. We can't generate those kinds of currents. But
• 54:02
  Speaker 1: what we can do is look at the magnetic field
• 54:05
  Speaker 1: of the Earth, which is generated we think by flowing
• 54:08
  Speaker 1: currents of ionized particles deep inside the Earth and the
• 54:12
  Speaker 1: magnetic field, of course, in the electric field are closely connected.
• 54:14
  Speaker 1: You have this dynamo effect where the magnetic field pushes
• 54:18
  Speaker 1: on these things and makes them to spin faster and
• 54:20
  Speaker 1: creates an electric field which creates the magnetic field sort
• 54:22
  Speaker 1: of self propagating. So by studying the details of the
• 54:25
  Speaker 1: magnetic field, we can get a sense for how electrically
• 54:28
  Speaker 1: conductive the earth is, and the presence of water in
• 54:31
  Speaker 1: the mantle will change that conductivity. And again they see
• 54:36
  Speaker 1: evidence for conductivity changes that are consistent with there being
• 54:40
  Speaker 1: a lot of water underground. That's amazing. So so it
• 54:44
  Speaker 1: seems like we do have a good amount of water underground.
• 54:49
  Speaker 1: What does that mean? Does that mean that we're constantly
• 54:52
  Speaker 1: surfing from our upper levels? I mean, I guess we are,
• 54:55
  Speaker 1: because even without water, the lower layers are moving around
• 55:00
  Speaker 1: and sort of like this unmelted wax situation. But what
• 55:04
  Speaker 1: is next for this water? Are we going to try
• 55:06
  Speaker 1: to drill down and import it for rich people to drink?
• 55:09
  Speaker 1: It's a really cool question. One study I read recently
• 55:13
  Speaker 1: found a spot in the Baffin Islands in Canada where
• 55:17
  Speaker 1: sort of the mantle is much closer to the surface,
• 55:20
  Speaker 1: where it's like actually maybe accessible. There's less crust and
• 55:23
  Speaker 1: more mantle, and they found samples that have a lot
• 55:25
  Speaker 1: less heavy water than the surface water. So what that
• 55:29
  Speaker 1: suggests is that this ocean of water that makes up
• 55:32
  Speaker 1: Us and the Pacific and the Lake superior and all
• 55:34
  Speaker 1: that kind of stuff may have been like late arrivals
• 55:37
  Speaker 1: from comets and asteroids, but the Earth may have had
• 55:41
  Speaker 1: five to ten oceans of water inside it from when
• 55:45
  Speaker 1: it formed, so like the true Earth water, the original
• 55:48
  Speaker 1: Earth water is still deep underground somewhere, and it's not
• 55:52
  Speaker 1: mixing very well. Like people don't think that the water
• 55:54
  Speaker 1: that was in the Earth could have gotten there from
• 55:57
  Speaker 1: asteroids and commets. There isn't time for it to like
• 56:00
  Speaker 1: flow all the way down to the mantle, even in
• 56:02
  Speaker 1: the billions of years. So it's almost like we have
• 56:05
  Speaker 1: two separate water cycles, you know, the surface water and
• 56:08
  Speaker 1: then the internal water, and the two haven't really mixed
• 56:10
  Speaker 1: very much. If that's really interesting. It makes me wonder,
• 56:14
  Speaker 1: do you know if there's any importance in terms of
• 56:16
  Speaker 1: the fact that this water hasn't mixed with our surface
• 56:19
  Speaker 1: water in terms of the chemical composition of Earth's water,
• 56:24
  Speaker 1: Like what having you know, less heavy water change our
• 56:28
  Speaker 1: oceans at all. I don't think having less heavy water
• 56:30
  Speaker 1: would make much of a difference on like our biology
• 56:33
  Speaker 1: or anything like that. It's really tiny, tiny fraction. It's
• 56:35
  Speaker 1: more useful. It's like a fingerprint. It's I think most
• 56:38
  Speaker 1: helpful for understanding like how do these planets form? Where
• 56:41
  Speaker 1: is the water on them? It's also really useful for
• 56:44
  Speaker 1: thinking about other solar systems. You know, we're looking at
• 56:47
  Speaker 1: other planets out there and other solar systems and wondering
• 56:49
  Speaker 1: like is there water on them? Now we can also
• 56:52
  Speaker 1: be wondering like is there water in them? Some of
• 56:54
  Speaker 1: the models I read suggested that, you know, while most
• 56:57
  Speaker 1: of the water that was on the surface got vaporized,
• 57:00
  Speaker 1: the water may have like clumped together with blobs of
• 57:03
  Speaker 1: dust as the Earth was forming and protected itself sort of,
• 57:07
  Speaker 1: and these primordial blobs of water then got like tucked
• 57:09
  Speaker 1: deep into the earth. And we've talked so far about
• 57:12
  Speaker 1: like what's in the mantle, but people wonder like it
• 57:15
  Speaker 1: does the core also have water? You know, the core
• 57:18
  Speaker 1: they think is iron and nickel, But for a long
• 57:20
  Speaker 1: time there's been a question about whether there's anything else
• 57:23
  Speaker 1: in there. We knew know that the core is a
• 57:25
  Speaker 1: little bit less dense than we expect, Like if you
• 57:27
  Speaker 1: imagine the core is just iron and nickel, it should
• 57:29
  Speaker 1: be a little bit heavier than the core that we have.
• 57:32
  Speaker 1: So now they're wondering, like maybe there's a bunch of
• 57:34
  Speaker 1: water mixed in with the core. That's what's making it
• 57:37
  Speaker 1: less dense. And one study irate suggested it might have
• 57:40
  Speaker 1: up to eighty oceans of water. That's eight zero oceans
• 57:45
  Speaker 1: of water mixed into the core. So you know, a
• 57:47
  Speaker 1: tiny fraction of the surface water is us It turns
• 57:50
  Speaker 1: out a tiny fraction of the water on Earth might
• 57:52
  Speaker 1: be the surface like the Pacific could just be a
• 57:55
  Speaker 1: drop in the oceans that are inside the Earth. That's incredible.
• 57:59
  Speaker 1: And so no owing or suspecting that there may be
• 58:02
  Speaker 1: a lot of water content, say in the core or
• 58:05
  Speaker 1: at least in the lower mantle, does that change how
• 58:10
  Speaker 1: we understand how geology works. It certainly is. It's affecting
• 58:15
  Speaker 1: our ideas for how these layers form and what they
• 58:18
  Speaker 1: can do because they have water in it. You know,
• 58:20
  Speaker 1: this is early days. This is like a pretty basic
• 58:22
  Speaker 1: question about what's in the Earth, like how much water
• 58:25
  Speaker 1: is there that we're only beginning to probe. And so
• 58:28
  Speaker 1: what it tells you is that, like we have very
• 58:30
  Speaker 1: little understanding of what's going on inside our own planet.
• 58:34
  Speaker 1: Very basic stuff is just now being investigated and probably
• 58:37
  Speaker 1: there are future discoveries ahead, you know, about what's going
• 58:40
  Speaker 1: on inside the Earth that will blow our geologists minds
• 58:43
  Speaker 1: and send them all to the bar for more cosmic cocktails.
• 58:46
  Speaker 1: And they didn't even need to send Bruce Willis in
• 58:48
  Speaker 1: a giant drill to the center of the Earth. That's
• 58:51
  Speaker 1: right exactly. And I love how we can sort of
• 58:54
  Speaker 1: see inside the Earth using all of these clayer techniques.
• 58:57
  Speaker 1: And maybe there are more ways to auty of this
• 59:00
  Speaker 1: stuff that nobody has thought of it. Maybe somebody out
• 59:02
  Speaker 1: there who's listening will invent a new way to probe
• 59:05
  Speaker 1: inside the Earth, to X ray it, to give us
• 59:07
  Speaker 1: a sense for like where that water is. Because I
• 59:10
  Speaker 1: suspect that we're in for a lot more surprises. Yeah,
• 59:13
  Speaker 1: I think tickling the Earth and see if it sneezes
• 59:16
  Speaker 1: anything out of its volcanoes. All right, well, thanks everyone
• 59:22
  Speaker 1: for coming along on this journey inside the Earth as
• 59:25
  Speaker 1: we drink deep into the mysteries of the Earth's formation
• 59:28
  Speaker 1: and it's current composition. And thanks Katie very much for
• 59:32
  Speaker 1: joining us today and drinking deeply of the mysteries of
• 59:34
  Speaker 1: the universe. Thanks for having me. And now I am
• 59:37
  Speaker 1: only going to have water if I know it was
• 59:39
  Speaker 1: imported from the art cloud. Very high maintenance and look
• 59:44
  Speaker 1: out for our new fancy influencers supported bottles of Water
• 59:47
  Speaker 1: Water Water. Thanks everyone for joining us. Tune in next time.
• 59:59
  Speaker 1: Thank you're listening, and remember that. Daniel and Jorge Explain
• 1:00:02
  Speaker 1: the Universe is a production of I Heart Radio. For
• 1:00:05
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• 1:00:12
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