Speaker 1: Welcome to tech Stuff, a production from I Heart Radio.
Speaker 1: Hey there, and welcome to tech Stuff. I'm your host,
Speaker 1: Jonathan Strickland. I'm an executive producer with I Heart Radio
Speaker 1: and How the Tech Are Young. We are about to
Speaker 1: listen to a classic episode of tech Stuff. This episode
Speaker 1: originally published in March. It is called ice core Drilling.
Speaker 1: Pretty cool if you asked me, enjoy. I like to
Speaker 1: think about ancient times, so when I come on other shows,
Speaker 1: I like to be able to look to the past sometimes.
Speaker 1: So Jonathan, I want to talk to you about Lake Vostock.
Speaker 1: All right, So what is Lake Vostock. You've never heard
Speaker 1: of it. I know Lake Lanier. Is it near Lake Lanier?
Speaker 1: It's pretty close. No, it's a lake in Antarctica. But
Speaker 1: it's not just any kind of lake. It's a sub
Speaker 1: glacial lake, the biggest one in the world actually. So
Speaker 1: it is a lake that is under a glacier, a
Speaker 1: giant sheet of ice, and that glacier is really thick.
Speaker 1: I've seen estimates from about two miles thick to about
Speaker 1: four thousand meters of glacial ice over the lake, which
Speaker 1: would be like two and a half miles. I guess
Speaker 1: they're probably different segments where the ice is a different thickness,
Speaker 1: and it's been buried in ice for millions of years,
Speaker 1: al right, So in recent decades, scientists have been drilling
Speaker 1: samples of the ice above this lake to study what's
Speaker 1: down there. Um And whenever I picture this lake in
Speaker 1: my mind, this lake buried under ancient ice, it makes
Speaker 1: me think of Gollum's Lake under the mountain in the
Speaker 1: Hobbit in the misty Mountains. Yeah, misty mountains. What did
Speaker 1: the lake have a name or was it just where
Speaker 1: the yummy fishes. I don't think it had a specific name.
Speaker 1: If it did, it would have been a Goblin name,
Speaker 1: so I would be, you know, unpronounceable for a mere
Speaker 1: mortal that I am. Oh, I assume you speak Goblin.
Speaker 1: I know grish Nacht is fire. That's the only thing
Speaker 1: I can I can rattle off off the top of
Speaker 1: my head. Well, anyway, when scientists drill down into this deep,
Speaker 1: deep Antarctic golem lake below the ice, one of the
Speaker 1: craziest things is that they've found d n A and
Speaker 1: evidence of microbial life. And I remember there were stories
Speaker 1: about how some ice samples indicated there might even be
Speaker 1: more complex life like fish and arthropods in that water. Um. Now,
Speaker 1: I know that was highly controversial at the time. I
Speaker 1: just recently looked it up again to see if there
Speaker 1: were there were any developments on that. I found a
Speaker 1: piece of coverage from Nature News at the time throwing
Speaker 1: some serious doubts on the on the live fish and
Speaker 1: arthropods claim. So that's I'm sure not all that widely accepted,
Speaker 1: but just the idea of it is so cool that
Speaker 1: you have this completely sealed off ancient alien life in
Speaker 1: this lake below a mountain of ice, and things like
Speaker 1: that make me think about deep time, Like how ice
Speaker 1: is a cross section of geological time on Earth right,
Speaker 1: Like there is layer upon layer of evidence of what
Speaker 1: has happened in the past. Yeah. And and just in
Speaker 1: case people are curious, like how could a subglacial lake
Speaker 1: remain Why would you call that a lake? Why would
Speaker 1: that not just be another part of the glacier. Why
Speaker 1: wouldn't that just be ice? Geothermal heat actually counteracts the
Speaker 1: freezing action of the ice above it, allowing the lake
Speaker 1: to remain liquid. Oh, I actually didn't know why it
Speaker 1: was liquid. Oh yeah, it's because of geothermal geothermal vents
Speaker 1: that continue to keep the temperature of the lake above freezing.
Speaker 1: So yeah, that's why, uh there can be a lake,
Speaker 1: a sub glacial lake, because otherwise you would say, like, well,
Speaker 1: wait a minute, how could it still remain how could
Speaker 1: it remain unfrozen unless there are some other chemicals in
Speaker 1: the lake that would uh lower its freezing point below
Speaker 1: that of water. That's fascinating. Yeah, well, okay, you might
Speaker 1: be wondering, wait a minute, what does this have to
Speaker 1: do with technology. Well, we're getting get there in just
Speaker 1: a second. So when you think about glaciers, I guess
Speaker 1: at the polar regions. How do things like that form?
Speaker 1: It's actually a pretty simple process. Every year it snows,
Speaker 1: it'll it'll snow, and you get heavier snows in the
Speaker 1: winter and lighter snows in the summer. Right, But in
Speaker 1: some places in the world, unlike probably wherever you live,
Speaker 1: if it snows around your house or your yard, eventually
Speaker 1: that snow melts, right, right, you get to a point
Speaker 1: where the season's warm, the snow starts to uh to
Speaker 1: melt away, and then eventually you have no more snow.
Speaker 1: But there's some regions where either the snow accumulation is
Speaker 1: so great that it never completely melts or the temperature
Speaker 1: never rises above freezing and therefore it just continues to accumulate.
Speaker 1: So every season you get a new layer of snow.
Speaker 1: What happens when a new layer of snow goes on
Speaker 1: top of the old layer of snow, Well, eventually it
Speaker 1: gets kind of heavy. Yeah, it compresses in to the
Speaker 1: point where the lower layers of snow are compressed into ice.
Speaker 1: So then you get layers of ice. And if you
Speaker 1: were able to look at these layers of ice collectively,
Speaker 1: you could start to draw some conclusions about what had
Speaker 1: happened the years when that snow first accumulated. And this
Speaker 1: is what leads us to the practice of drilling down
Speaker 1: into ice sheets and glaciers to retrieve samples to kind
Speaker 1: of get a look back into the geological past of
Speaker 1: the Earth. Yeah, exactly, So ice core drilling is a
Speaker 1: way of getting at this cross section of geological time
Speaker 1: that we can see in the ice layers of glaciers,
Speaker 1: and a lot of it's going to be you know
Speaker 1: and play like Greenland or in Antarctica. Those are the
Speaker 1: two chief sites for ice core drilling, where people have
Speaker 1: to come up with these huge vertical samples of ice
Speaker 1: that might be miles thick, right, And what I wanted
Speaker 1: to know was, how on earth do they do that?
Speaker 1: It can't be all that easy, can it is? It's
Speaker 1: well easy, It is not simple. It is similar than
Speaker 1: I would have expected, actually it is. It is a
Speaker 1: simple method in the sense that it doesn't require tons
Speaker 1: of complex machinery or techniques. But it is not easy
Speaker 1: to do because it is difficult to reach to access
Speaker 1: the areas, and the methodology can often require people to
Speaker 1: essentially live on an ice sheet for a very you know,
Speaker 1: like like a month at a time, depending on how
Speaker 1: deep they want to drill. Right. So, uh, Within each
Speaker 1: of those layers of snow that have turned into ice,
Speaker 1: there are records of things of the past, like the
Speaker 1: you know, ice can trap chemicals, for example, precipitation can
Speaker 1: trap chemicals, and as that precipitation, in this case, snow
Speaker 1: hits the ground, then you have a record of what
Speaker 1: the chemical composition was at that given time. And then
Speaker 1: other layers will pack on top of it and they
Speaker 1: will have their own kind of you know, unique chemical fingerprint,
Speaker 1: if you will. The layers don't just show you a
Speaker 1: cross section of time. Each layer has data from the
Speaker 1: time it comes from. It might even have like ash
Speaker 1: from volcanic eruption. You can see chemical data like you
Speaker 1: were just talking about the concentrations of different gases in
Speaker 1: the atmosphere that become dissolved in little bubbles in these layers,
Speaker 1: or you can see exactly ash from volcanic eruptions. You
Speaker 1: can even discern things about the local weather patterns where
Speaker 1: the glacier was at certain times in the past. We'll
Speaker 1: be back with more about ice core drilling in just
Speaker 1: a moment, but first let's take a quick break. Another
Speaker 1: thing that I think is kind of cool with the
Speaker 1: volcanic ash layers is that it lets you compare one
Speaker 1: sample against another sample that was gathered somewhere else and
Speaker 1: not necessarily justin ice. There are other core uh coreing
Speaker 1: methods like that, going through peat bogs, for example, And
Speaker 1: if you find a layer of ash that corresponds to
Speaker 1: another layer of ash and a completely different sample, you
Speaker 1: can say, oh, well, these both came from that same eruption.
Speaker 1: That allows us to to corus correlate these two dates
Speaker 1: together by the chemical composition of the ash and the
Speaker 1: two layers, because the chemical composition is going to be
Speaker 1: unique each eruption, So that way you can actually start
Speaker 1: to build a global view of what had happened during
Speaker 1: any given you know, uh year or span of years
Speaker 1: in Earth's past, which is really interesting. I think. Yeah,
Speaker 1: it's way cooler and more full of creep be ancient
Speaker 1: power than you would have imagined ice drilling to be.
Speaker 1: But I want to hear about the drilling itself. How
Speaker 1: do they get these cores out of the glacier? Okay, Well,
Speaker 1: there are two basic categories of drills, and then there
Speaker 1: are are of you know, different examples of each category.
Speaker 1: So the first big one are mechanical drills. Now, these
Speaker 1: are drills that drilled down into the ice through mechanical action,
Speaker 1: essentially rotating. Right. But normally when you think of a
Speaker 1: drill that's making a hole in something, you are not
Speaker 1: removing any section of that substrate intact. You're just making
Speaker 1: a hole. I'm drilling in the wall. Well, it's going
Speaker 1: to be this sort of like you know, cylindrical object
Speaker 1: that's got screw thread kind of things on the outside
Speaker 1: to move the shavings out of the hole as it
Speaker 1: goes deeper in. It's just a solid knot. Yeah, it's
Speaker 1: not going to give you a cross section of the wood.
Speaker 1: So how do you get that? So in order to
Speaker 1: do that, you have to have a drill bit that
Speaker 1: is is an actual hollow cylinder right the middle of this.
Speaker 1: Instead of it being a solid shaft, it's a cylinder
Speaker 1: that has cutting teeth on one end of it, so
Speaker 1: that when it rotates, it creates this the the the
Speaker 1: actual drill itself rotates around a column of ice, it
Speaker 1: creates a column of ice cuts away so that you
Speaker 1: know the center of the drill bit starts to accumulate
Speaker 1: this ice. It goes straight down until you get to
Speaker 1: the length of the drill itself, and obviously then you
Speaker 1: can't go any further because you hit the cap, like
Speaker 1: the top of the drill, and that's where you would
Speaker 1: have to stop and try and retrieve the ice that
Speaker 1: you've just drilled. Right, So you might think about it
Speaker 1: kind of like this. Imagine like a tin can or
Speaker 1: like a pipe, and then the lip of that pipe
Speaker 1: is sort of like a circular saw blade. It's got
Speaker 1: the blade is parallel to the length of the pipe obviously,
Speaker 1: so it can screw down in right, and it's also
Speaker 1: the teeth are usually adjustable, like you can either uh
Speaker 1: extend them or attract them a little bit, depending upon
Speaker 1: the nature of the ice that you're cutting into. So,
Speaker 1: for example, if they are if the if the teeth
Speaker 1: are retracted too far, it's gonna be really hard to
Speaker 1: get purchase on the ice. It's gonna kind of skitter around.
Speaker 1: Anyone who's had any experience with ice, nos, it's slippery,
Speaker 1: and so you'd have to have the teeth be a
Speaker 1: little bit longer. If they're too long, then they're going
Speaker 1: to get caught in the ice. So it'll make it
Speaker 1: more difficult to turn the drill and drill down into
Speaker 1: the ice. So you have to find that that sweet spot.
Speaker 1: And that's usually why the the teeth are adjustable, so
Speaker 1: that you can make it the perfect length for whatever
Speaker 1: conditions you encounter. You when you turn the drill the
Speaker 1: proper way, it cuts into the ice and it and
Speaker 1: it pulls in that cylinder like we were talking about. Now,
Speaker 1: there's also gonna be some waste product from this drilling
Speaker 1: in there. Yeah, chips of ice obviously are going to accumulate,
Speaker 1: so uh often these drills have treads on the outside
Speaker 1: of them, which will put push chips up to the surface.
Speaker 1: Some of them have chambers that will hold chips to
Speaker 1: keep it away from the ice core sample, because obviously,
Speaker 1: if you're looking at at creating a sample for you
Speaker 1: to study in the lab, you don't want to end
Speaker 1: up mixing that material all up, because then you don't
Speaker 1: have an accurate representation of what happened over any given
Speaker 1: length of time. Right, You've you've corrupted your sample. So
Speaker 1: most of these have a method of funneling chips up
Speaker 1: into a chamber. Uh. And you know, are the the
Speaker 1: simplest of these mechanical drills are the hand powered augers.
Speaker 1: You actually move these by hand. It looks like a
Speaker 1: kind of like a very long can, right, and the
Speaker 1: top of it has like a t junction handle, and
Speaker 1: like in cartoons when people have a dynamite box and
Speaker 1: they push it right or like a jackhammer, you know
Speaker 1: that kind of thing, And except of course, instead of
Speaker 1: going up and down, you're twisting this in order to
Speaker 1: create the rotational force. This translated into lateral force because
Speaker 1: the drill is kind of like a the inversion of
Speaker 1: a screw, right, So you're you're drilling down that way.
Speaker 1: And you might think, well, you were talking earlier about
Speaker 1: how some of the UM the core samples. We look
Speaker 1: at our our kilometers long. How could you possibly get
Speaker 1: a sample that's that long using a handogger? Well, first
Speaker 1: of all, you can't, but secondly, uh, when we talk
Speaker 1: about these core samples, Yeah, the entire sample might be
Speaker 1: several kilometers long, but that's made up of segments. So
Speaker 1: depending upon the drill you're using, your segments maybe between
Speaker 1: one and six meters long, right, so uh, that's between like, uh,
Speaker 1: you know, around three ft two around twenty ft long roughly,
Speaker 1: um And in order for you to create a full
Speaker 1: uh core sample, than what you would have to do
Speaker 1: is lower the drill back down into the borehole that
Speaker 1: you've started until it reaches the bottom, and you have
Speaker 1: to use extenders to come up out of the borehole
Speaker 1: so you can continue to drill downward. That sounds like
Speaker 1: you pretty quickly reach a sort of maximum depth. For
Speaker 1: these hand operated versions, you absolutely do, yeah, because eventually
Speaker 1: you're not going to the the amount of rotational force
Speaker 1: you'll have to create to rotate the entire thing, the
Speaker 1: the drill and all the extenders will exceed the strength
Speaker 1: and flexibility of that device, So you can't you can't
Speaker 1: indefinitely use a handogger. It would also just seem to
Speaker 1: be that that combined with whatever you have to hang
Speaker 1: it on to get it deeper and deeper, would get
Speaker 1: really heavy. Yeah. Yeah, you know, you keep in mind
Speaker 1: like you're talking about lifting up six meters of ice. Uh,
Speaker 1: And of course the diameter of this depends upon the
Speaker 1: drill to write the drill, the drills diameter will determine
Speaker 1: the diameter of the core sample. But you're still talking
Speaker 1: about lifting all that ice, which is heavy lifting the
Speaker 1: drill itself, which is heavy lifting all the extenders, which
Speaker 1: are heavy. So eventually you get to a point where
Speaker 1: you know you're just not gonna have the integrity to
Speaker 1: keep that all together, which is when you need to
Speaker 1: look at possibly switching to something else. So your typical
Speaker 1: handoggers can go pretty darn deep. I mean, we're talking
Speaker 1: twenty to thirty meters, that's like sixty six ft. That's
Speaker 1: deeper than I would have expected. Yeah, me too, And
Speaker 1: according to some of the things I read, it's more
Speaker 1: like fortys is the maximum. Twenty to thirty tends to
Speaker 1: be what people limit themselves to. But I think the
Speaker 1: record was somewhere around forty so it's even further than that. Um.
Speaker 1: So what do you do when you reach that that
Speaker 1: limit where you can't use the handoggers anymore? Well, that's
Speaker 1: when you try try kind of. You're using the electro
Speaker 1: mechanical drills. These are suspended on a cable, so instead
Speaker 1: of it having like a physic cool um turning mechanism
Speaker 1: that extends all the way up to the surface there,
Speaker 1: they they are actually suspended by cable lowered into a
Speaker 1: borehole and they consist typically of two barrels. You have
Speaker 1: an external barrel that remains uh motionless, it is, it
Speaker 1: does not turn all right, So the external barrel is
Speaker 1: uh just a stationary holding device. Then the inner barrel
Speaker 1: is the one that can rotate, all right. So the
Speaker 1: cable that suspends an electro mechanical drill, the cable doesn't
Speaker 1: move at all either. It's just there to supply the
Speaker 1: suspension mechanism and the power. So it's it's got the
Speaker 1: power lines that go down to power the drill. The
Speaker 1: inner barrel will rotate in the proper direction to continue
Speaker 1: drilling down. And the inner barrel also has treads on
Speaker 1: the external side of it, right, So those are going
Speaker 1: to be like the threads on your drill little bit
Speaker 1: that are getting the shavings out of the wall and
Speaker 1: the expa they're transporting the ice chips up along the
Speaker 1: length of the drill. That's right, and so you would
Speaker 1: use this the same way you would use your handdogger,
Speaker 1: except of course, in this case it's an electrical uh action,
Speaker 1: electro mechanical action that is causing it. So it's you know,
Speaker 1: it's a it's a little bit easier on the people
Speaker 1: who are operating it. They just have to make sure
Speaker 1: that they're lowering it properly, and then it's at the
Speaker 1: correct depth all of that kind of stuff, and and
Speaker 1: that the teeth are at the right length. It's just
Speaker 1: like the handdoggers. You've got to make sure that those
Speaker 1: those teeth are are proper so that they can cut
Speaker 1: into the material to ice properly. Uh So, usually you
Speaker 1: also have another cool mechanism literally to hold the ice
Speaker 1: in place. Once you've reached the point where you're ready
Speaker 1: to lift up the next segment. They have spring loaded
Speaker 1: lever arms inside that inner barrel that think of it
Speaker 1: like little pincers that come in and hold that core
Speaker 1: in place. Because you want it to be really steady.
Speaker 1: When you're lifting that drill up. You know, you're talking
Speaker 1: forty or more up a borehole. You don't want to
Speaker 1: lose the grip on that ice core sample because that
Speaker 1: would be bad. So the spring loaded lever arms hold
Speaker 1: them and they are called something that I love, core dogs.
Speaker 1: It's like it's like going to the county fair. You
Speaker 1: get yourself and a couple of core dogs. I like
Speaker 1: to go to Pelucaville to get my core dogs. Local
Speaker 1: establishment here in Atlanta. Now there is another type of
Speaker 1: drill that I love. Yeah, I think this is excellent.
Speaker 1: I love looking at the picture. I was looking at
Speaker 1: a picture of this before I read about what it was,
Speaker 1: and I was like, I don't understand how it cuts
Speaker 1: because it just looked like a pipe with kind of
Speaker 1: a strange lip. It didn't have any teeth, right, And
Speaker 1: then I read about it and I was like, oh,
Speaker 1: I see it doesn't thermal drill. Yeah, so it's using heat. Yeah,
Speaker 1: So imagine sort of a pipe that on the end
Speaker 1: of the lip at the pie ape has a heating
Speaker 1: element and it gets hot, melts straight through the ice
Speaker 1: and just sinks on down there. Yeah. Yeah, until you
Speaker 1: get to again to the end of the capacity of
Speaker 1: the drill, and then you have to lift it back
Speaker 1: up again. So yeah, it's really I love that idea,
Speaker 1: the idea of of of let's just use heat to
Speaker 1: work our way. I mean, come on, it's ice, let's
Speaker 1: use heat to melt away down there. Yeah. That actually
Speaker 1: does seem like you would have some limitations though, and
Speaker 1: it does. In fact, you are you're more likely to
Speaker 1: use that when you're using ice that is above minus
Speaker 1: ten degrees celsius for example, you don't know, which is
Speaker 1: fourteen degrees fahrenheit. By the way, you wouldn't use that
Speaker 1: in colder areas because the melt off the water that
Speaker 1: you would be creating as the heating element melts, the
Speaker 1: ice would likely start to refreeze and that would become
Speaker 1: a problem. So you are more likely to use it
Speaker 1: in uh in quote unquote warmer since you waitions it
Speaker 1: will still be really cold. Um. And then if you
Speaker 1: were to encounter those colder situations, you would use electro
Speaker 1: mechanical drill. And in fact, there are plenty of ice
Speaker 1: core drilling projects that that will switch out the drills
Speaker 1: based upon whatever the current conditions happen to be as
Speaker 1: they are drilling. You've got a little bit more show
Speaker 1: to go before we get to that. We're gonna take
Speaker 1: one more quick break now. I would imagine that once
Speaker 1: you get down to a certain depth, the whole enterprise
Speaker 1: sort of changes. I mean, once you're getting two thousands
Speaker 1: of feet down, you're going to start dealing with the
Speaker 1: ways that ice behaves kind of like a plastic and yeah,
Speaker 1: do you know what I mean. You gotta remember this
Speaker 1: ice is under a lot of pressure. I mean, just
Speaker 1: from wait alone, it's under a ton of pressure. But
Speaker 1: there's also there are other elements there too. There's glacial flow, right,
Speaker 1: glaciers move, they don't move very quickly, but there is
Speaker 1: this pressure from glacial flow where the glacier is potentially
Speaker 1: moving in a specific direction, which means that's putting pressure
Speaker 1: on the borehole too. And if the pressure is too great,
Speaker 1: that borehole can close, and by clothes, we've pretty much
Speaker 1: mean collapse in on itself. Like closing sounds pretty gentle,
Speaker 1: it's not a gentle thing. Well, whether it's gentle or not,
Speaker 1: it's a big problem for your research project exactly. So, Uh,
Speaker 1: there are times where you will have these these projects
Speaker 1: where they will start pumping liquid down the whole, and
Speaker 1: there's a couple of different reasons for this. Some will
Speaker 1: pump anti freeze liquid down the whole in order to
Speaker 1: make sure that any melted runoff, for example, if you're
Speaker 1: using a thermal drill doesn't refreeze, but then you may
Speaker 1: need to put down a different type of liquid, another
Speaker 1: one that would be less likely to freeze, in order
Speaker 1: to equalize the pressure from inside the hole to what
Speaker 1: what is outside the hole. Yeah, I read somewhere that
Speaker 1: the drill fluid that they would normally use can be
Speaker 1: something like kerosene, like a petroleum derived fluid. Uh, And
Speaker 1: it just basically has to have the right freezing point.
Speaker 1: And they wanted to be of a certain thickness right
Speaker 1: right because they have to you know, if it's if
Speaker 1: it's too thin, then it's not going to create the
Speaker 1: pressure that they need in order to keep the whole stable.
Speaker 1: And if the freezing point is too is too high,
Speaker 1: then it's going to just end up mucking everything up anyway.
Speaker 1: So it is a delicate balance. There's one project in
Speaker 1: particular I wanted to talk about the kind of give
Speaker 1: an idea of what it's like to work on one
Speaker 1: of these. Again, it all depends upon how deeply you
Speaker 1: need to go when you're retrieving the ice core sample.
Speaker 1: You know, how far back are you going to be looking. Uh.
Speaker 1: There's one called the West Antarctic Ice Sheet Divide Project.
Speaker 1: There's a recent effort by the United States and which
Speaker 1: an ice core that was three thousand, four hundred five
Speaker 1: meters long, so three point four kilometers long, was retrieved
Speaker 1: over the course of six field seasons. Now, they defined
Speaker 1: a field season as approximately forty days of drilling. The
Speaker 1: actual drilling took place six days a week, so obviously
Speaker 1: more than um. Since you're not drilling seven days a week.
Speaker 1: Forty days of drilling is you know, you've got to
Speaker 1: divide that up properly. But twenty four hours a day,
Speaker 1: three shifts UH for drilling per day, with three UH
Speaker 1: project workers per shift, so nine people working for six
Speaker 1: days a week and drilling is going on twenty four
Speaker 1: hours a day. I'm sure that's not an easy job,
Speaker 1: but I would kind of like that job just to
Speaker 1: be able to say I drilled course of ancient ice
Speaker 1: at one of my past jobs. But you might you
Speaker 1: might have some interesting stories to tell about the the
Speaker 1: the quirks of the two shift workers you shared all
Speaker 1: that time with and whether or not you ever want
Speaker 1: to see that person ever again. To the two am
Speaker 1: to ten am shift is kind of rough in Antarctica.
Speaker 1: You can also just be like, I will never not
Speaker 1: hear the sound of ice being drilled. It is just
Speaker 1: gonna go through my head through the rest of my days.
Speaker 1: But anyway, Yeah, it's it's a really serious endeavor and
Speaker 1: it's very important scientific work. And so because it's important,
Speaker 1: and because this is something that you know, once you
Speaker 1: once you have retrieved the ice core sample, you've only
Speaker 1: just started, you have to make sure that you can
Speaker 1: store them properly so that you have the chance to
Speaker 1: actually examine them later. Right, So you've got these cylindrical
Speaker 1: segments of you know, essentially priceless scientific data that are
Speaker 1: just in containers. And yeah, and it's perishable. It's perishable.
Speaker 1: There's something that's beautiful about this to me, the fleeting
Speaker 1: nous of it. How you know, this is something that
Speaker 1: could be millions of years old, but it's frozen bran.
Speaker 1: It could melt if the power goes off. You know, now,
Speaker 1: to be fair, if you're getting them from Greenland. I
Speaker 1: think the oldest we've looked at is a hundred thirty thousand,
Speaker 1: and Antarctica it's more like eight thousand, so not quite millions,
Speaker 1: but still well before human history was ever recorded or
Speaker 1: potentially even possible to record. You know, we're talking way back,
Speaker 1: we're talking back when Cathulu was running rampant. Probably not,
Speaker 1: but at any rate, they would that be detectable from
Speaker 1: the highest we see dissolved particulates of I don't know, yeah,
Speaker 1: just like there's there's one of the chemical constituents of
Speaker 1: the old ones, right, you could be like, well, there
Speaker 1: was a frozen sugar right that right around this level.
Speaker 1: So we're pretty sure it was around this time at
Speaker 1: any rate. So we have to we have to store
Speaker 1: these things obviously until they can be examined by various scientists,
Speaker 1: and a lot of the ice cores when they are stored, like,
Speaker 1: there are a lot of different research facilities that want
Speaker 1: to have a chance to to examine this stuff, so
Speaker 1: they have to go to a special facility to do that.
Speaker 1: One of those is the National Ice Core Laboratory, which
Speaker 1: stores more than seventeen thousand meters of ice that's incredible.
Speaker 1: And its main archive freezer is fifty five thousand cubic
Speaker 1: feet in size, that's one thofty seven cubic meters, And
Speaker 1: so incoming ice has to first reach a thermal equilibrium
Speaker 1: with the temperature inside the freezer, which is minus thirty
Speaker 1: six degrees celsius or minus thirty two point eight fahrenheit.
Speaker 1: And the reason for that is obviously you don't want
Speaker 1: to start handling the ice before it's reached thermal equal
Speaker 1: equilibrium for fear of damaging the sample. Right, So once
Speaker 1: it's reached that thermal equilibrium, that's that only then can
Speaker 1: you actually unpack it and then label it and and
Speaker 1: racket categorize it. I've seen pictures of these two ridge facilities.
Speaker 1: It looks like kind of like a National Film Archive
Speaker 1: or something that's got these silver cans and the shelves
Speaker 1: going to the ceiling. Though I do wonder that if
Speaker 1: there's a temptation for people working in these places every
Speaker 1: now and then to get a little cheeky and make
Speaker 1: themselves a highball, it's just just an ancient on the rocks, right, Yeah,
Speaker 1: on the ancient rocks. I guess. Then again, you may
Speaker 1: be unleashing microbes into your into your body that you
Speaker 1: have no natural defenses. Again, Yeah that that. Yeah, I
Speaker 1: see that. We're kind of starting to mix up movie
Speaker 1: genres too, because this is kind of a rolling emeric,
Speaker 1: you know, kind of into the world derivative, right, and
Speaker 1: then and then Judd Apatel where you get like the
Speaker 1: kind of stoner comedy. So you get like the stoner
Speaker 1: character who's just trying to make a drink. And then
Speaker 1: unleash is the terrible super flu Hey this this this,
Speaker 1: this particular bacteria or virus or whatever has been in
Speaker 1: suspended animation for hundreds of thousands of years now has
Speaker 1: been unleashed on the plant. There's money in this, Joe,
Speaker 1: I think we need to develop it. But before that
Speaker 1: we have to finish this podcast. So wait a second. Okay,
Speaker 1: So once they've got the ice, Yeah, you have this
Speaker 1: priceless repository of ancient data. How do you analyze it
Speaker 1: and what can you learn? Well, the first thing you
Speaker 1: can do is look at it. I know that sounds silly.
Speaker 1: You are a man of many insights using your eyeballs,
Speaker 1: so uh. The interesting thing about an ice core sample
Speaker 1: is you can actually see the passage of time just
Speaker 1: by looking closely at the ice core sample. Yeah, you
Speaker 1: should look up an image of this if you're listening
Speaker 1: on a computer or device where you can have internet access.
Speaker 1: It's cool. It's got stripes, yeah, and those stripes represent
Speaker 1: summers and winters, right. So winters are darker because you
Speaker 1: usually have much greater snow accumulation during the winter. Summers
Speaker 1: are lighter because you have less snow accumulation. So you
Speaker 1: get these dark bands separated by light bands, and together
Speaker 1: those represents a year's passage of time. Right, You've got
Speaker 1: the summer and winter there, and so you just start
Speaker 1: counting backwards. It's like rings on a tree, except you'd
Speaker 1: be counting vertical stripes rather than the concentric circle exactly. Yeah,
Speaker 1: So you count that backward and you can actually say, oh, well,
Speaker 1: this particular year is such and such because it's so
Speaker 1: many far back from the surface. And then you can
Speaker 1: start or at least you can estimate, like within a
Speaker 1: reasonable degree of certainty, what year that represents. And in fact, uh,
Speaker 1: they have done tests, they being scientists, have done tests
Speaker 1: to make sure that this is the case by looking
Speaker 1: at various layers identifying what year that layers should represent
Speaker 1: testing the chemical composition of that particular layer of the
Speaker 1: ice and comparing it to data that we have from
Speaker 1: others other means, like and we're talking like around the
Speaker 1: nineteen fifties, like looking at the nineteen fifties, so counting
Speaker 1: back until you hit to nineteen fifty on the ice
Speaker 1: core sample and then testing it to see if it
Speaker 1: actually matches the other records we have, and they match,
Speaker 1: so it shows that this actually does work. Now, however,
Speaker 1: that being said, when you start going to deeper levels,
Speaker 1: it starts getting more and more difficult to differentiate. Yeah,
Speaker 1: I think I was seeing various concerns about how factors
Speaker 1: in the physics of the glacier can change what happens
Speaker 1: to these levels. I mean, number one, you just have
Speaker 1: that more pressure, but I think the glacier flow can
Speaker 1: also change how the levels are represented, right, Yeah, yeah,
Speaker 1: I mean, if you if you think about like, these
Speaker 1: glaciers don't necessarily all move. It's like one big solid unit.
Speaker 1: Keep in mind that this is this is a a
Speaker 1: solid form of a fluid, but it still has some
Speaker 1: fluid mechanics to it, right, It's not not all of
Speaker 1: the glacier is necessarily moving. As in concert with itself, right,
Speaker 1: So you could have sections of the glacier that are
Speaker 1: moving that could end up changing a little bit of
Speaker 1: what you would expect to find as you're counting back
Speaker 1: to a certain depth. And so it's one of those
Speaker 1: things where, uh, you know, you have to after at
Speaker 1: some point you have to start looking at alternative means
Speaker 1: of dating that particular part of the ice core sample,
Speaker 1: and that could involve doing something like performing some geochemistry
Speaker 1: on it. So you look to see what materials are
Speaker 1: in that layer and how does that correspond with the
Speaker 1: records we have about our geological history. So it's usually
Speaker 1: mass spectrometry that we use where we try and see
Speaker 1: what chemicals are represented within that layer and kind of
Speaker 1: map that to what else we know about our history. Um,
Speaker 1: there's also that layers of ash. So if we find
Speaker 1: layers of ash, then we know that this is uh,
Speaker 1: you know, a mark of a volcanic eruption and based
Speaker 1: upon our records, we can kind of date it from
Speaker 1: that point. Or it could be just another emergence of hexus.
Speaker 1: Could be could be likely a volcanic eruption, but could
Speaker 1: be electrical conductivity because again depending on what the what
Speaker 1: materials are dissolved within that ice, it's going to be
Speaker 1: either more or less conductive, and so by doing that
Speaker 1: we can make determinations of what materials are in there
Speaker 1: and thus kind of get an idea of how where
Speaker 1: in the the timeline that particular part of the ice
Speaker 1: core sample falls. Numerical flow models which help us correlate
Speaker 1: age to depth. This is what we were talking about
Speaker 1: just a second ago, Joe, the idea of the glacial
Speaker 1: flow and how that can can make things a little
Speaker 1: more complicated. Uh, having those numerical flow models, which essentially
Speaker 1: that's a simulation of what must have happened within a
Speaker 1: particular body of ice over a given amount of time,
Speaker 1: and by modeling it and trying to get that as
Speaker 1: accurate as possible, we can try and correlate, all, right,
Speaker 1: at what depth would we consider, like, how how far
Speaker 1: down would we go before we hit I don't know,
Speaker 1: two thousand years for example. This is a kind of
Speaker 1: I'm just throwing that out there as as a off
Speaker 1: the top of my head example. And also radiometric dating dating,
Speaker 1: which is a not away for nuclear physicists to know,
Speaker 1: hang out and find that special someone. They use tender
Speaker 1: just like everybody else. It's more about actually looking at
Speaker 1: um radioactive decay. Not every layer of ice has anything
Speaker 1: in it like that, but some layers of ice do
Speaker 1: have trace amounts of uranium dust, and that would might
Speaker 1: be a way that we could date certain types. This
Speaker 1: is pretty deep in the Antarctic ice usually. Um As
Speaker 1: for what we can learn, we can learn lots of stuff, right,
Speaker 1: I mean, like it's really important information that tells us
Speaker 1: about the way our world has changed over huge expanses
Speaker 1: of time. Right. Well, I know one of the main
Speaker 1: things that scientists are looking at ice cores for these
Speaker 1: days is to help understand what past climate systems look
Speaker 1: like and to help predict what changes will be brought
Speaker 1: about by the current climate change we're observing right right,
Speaker 1: And of course you know, uh, you can't really make
Speaker 1: predictions without necessarily understanding what has happened in the past, right.
Speaker 1: You need to have that model there so that you
Speaker 1: can have something to base your predictions upon. So one
Speaker 1: thing you can easily see, and by easily I mean
Speaker 1: I described looking at those layers and seeing the summer
Speaker 1: and winter. You can easily see the general precipitation trends
Speaker 1: year over year by the thickness of those layers. Right,
Speaker 1: So if one summer winter layer is very thin compared
Speaker 1: to the next one below it, you could say, well,
Speaker 1: there was a year where there was a relatively heavy
Speaker 1: amount of precipitation followed by a year where there was
Speaker 1: very light precipitation. Then you could go and start doing
Speaker 1: more studies to see, like, while all, there are other
Speaker 1: elements inside this ice core that could indicate why that
Speaker 1: might have been the case. What what was going on
Speaker 1: in the atmosphere that would have made one year particularly
Speaker 1: heavy with precipitation and the following year light. Oh I see,
Speaker 1: So maybe you could just, for example, look at concentrate
Speaker 1: of different atmospheric chemicals in the layers preceding the layers
Speaker 1: that have more precipitation, so like, oh, wow, it's strange
Speaker 1: there was more nitrogen in the atmosphere the past three
Speaker 1: seasons before we had these heavy precipitation seasons. Or it
Speaker 1: might be look here, that's not a real result. And
Speaker 1: then you can also look and say, oh, look at
Speaker 1: the concentration of carbon dioxide for example. Now you've gotta
Speaker 1: be a little careful with this, particularly with the green
Speaker 1: Land examples, because carbon diox i can get dissolved in water,
Speaker 1: and sometimes they're they're also melting layers. Melting layers are
Speaker 1: where uh, you know, the temperaturey got high enough so
Speaker 1: that some snow had melted. The water can trickle down
Speaker 1: into the snowpack and you get these kind of bubble
Speaker 1: free areas of ice. That's a melt layer, which can
Speaker 1: still have a lot of useful information in it. But
Speaker 1: it also means that sometimes water that has carbon dioxide
Speaker 1: dissolved in it can set down into older layers and
Speaker 1: thus change the composition of them, giving you a false
Speaker 1: positive that there was more common carbon dioxide in a
Speaker 1: layer than there really was. Fortunately, scientists are aware of this.
Speaker 1: You know what to look for and uh and like
Speaker 1: I said, that's more prevalent in Greenland and Antarctica. You
Speaker 1: don't tend to see that same issue. But uh, you know,
Speaker 1: you can also look at things like, um, the chemical composition,
Speaker 1: which will tell you more about the concentration of greenhouse
Speaker 1: gases uh in any given year, and you can look
Speaker 1: for trends. Right, you can actually look and see like
Speaker 1: it may not be uh, this love layer was thick
Speaker 1: and that layer was thin. It maybe we're seeing a
Speaker 1: gradual decrease in layers over a really long time, followed
Speaker 1: by a period where they were very very thin layers
Speaker 1: for a long time, and then very thick layers as
Speaker 1: another ice age started coming on. You could actually see
Speaker 1: these big trends, because that's really what we're talking about
Speaker 1: with climate. Right, Climate isn't weather. We often, like the
Speaker 1: people often will conflay the two. Right, climate influences weather, right,
Speaker 1: and and climate is like you know, a weather is
Speaker 1: this is this localized, regional, temporal thing. Like it's happening
Speaker 1: in a very small time span. You're talking like, while
Speaker 1: the weather is terrible today, climate is long reaching. It
Speaker 1: can it's a global thing. It's not or at least
Speaker 1: a much larger regional thing. Um and it it is not. Uh,
Speaker 1: it's not as mercurial you could say, as weather would be,
Speaker 1: because weather can change dramatically day to day. Climate are
Speaker 1: these long trends. Describing climate would be like describing Jonathan's personality.
Speaker 1: Describing weather would be like can you believe what Jonathan
Speaker 1: said this morning? Yeah, we'll put so. Uh. By looking
Speaker 1: at this, we can say, all right, during this period
Speaker 1: of time where we know there was a greater concentration
Speaker 1: of greenhouse gasses because it was trapped in the ice.
Speaker 1: We have we have, uh, we've analyzed the ice. We
Speaker 1: know what the concentrations are. We can see from the
Speaker 1: following layers how that affected climate over a great span
Speaker 1: of time. So because our records don't stretch back that far, heck,
Speaker 1: our our weather records don't stretch back far at all.
Speaker 1: We're talking like a century or so, and otherwise we're
Speaker 1: we're relying upon things like the recollections that people had
Speaker 1: written down and either letters or or you know, just
Speaker 1: the general language used by people who are writing at
Speaker 1: the time what the weather might have been. Like. This
Speaker 1: is an actual way for us to look back and say,
Speaker 1: here's what the climate was a hundred thousand years ago,
Speaker 1: and here's what here's how the climate changed over a
Speaker 1: twenty thousand years span. I mean, it's a big picture
Speaker 1: look at something that otherwise we would just be making
Speaker 1: wild guesses about. And that's really interesting to me. Yeah,
Speaker 1: it's obviously incredibly useful. I have to say again, how much.
Speaker 1: Maybe it's just me, but anything that's that old gives
Speaker 1: me this very cool, mysterious feeling. I get a little
Speaker 1: try about it. Yeah, yeah, I mean, it's it's neat
Speaker 1: to know that there there exists a record where by
Speaker 1: applying careful scientific, careful scientific approach to analyzing that material,
Speaker 1: we can draw very very uh, very interesting conclusions about
Speaker 1: what the Earth was like well before humans were walking
Speaker 1: around and being human ish. I hope you enjoyed that
Speaker 1: classic episode about ice core drilling. If you have suggestions
Speaker 1: for topics I should cover in future episodes of tech Stuff,
Speaker 1: please reach out to me and let me know. The
Speaker 1: handle for the show on Twitter is text stuff hs
Speaker 1: W and I'll talk to you again really soon. Tech
Speaker 1: Stuff is an I Heart Radio production. For more podcasts
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