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How Ocean Currents Work · Stuff You Should Know

0:00
Speaker 1: Welcome to Stuff You Should Know from House Stuff Works
0:04
Speaker 1: dot com. Hey, and welcome to the podcast. I'm Josh
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Speaker 1: Clark with Charles W. Chuck Bryant, and Jerry and this
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Speaker 1: is Stuff you Should Know, the one about ocean currents.
0:21
Speaker 1: We should start titling our episodes like Friends did. Yeah,
0:25
Speaker 1: the one where Ross talks about ocean currents. Yeah, the
0:29
Speaker 1: one where Chuck's eyes glazed over. I love this stuff, man,
0:33
Speaker 1: Like Earth science really gets me jazz. That's good, it
0:37
Speaker 1: really does. Like it's so like, it's very detailed. There's
0:43
Speaker 1: a lot to it. It's often oversimplified, but it's also
0:48
Speaker 1: very understandable. And when you really like learn about it,
0:52
Speaker 1: you realize what an elegant system the whole thing is. Sure,
0:55
Speaker 1: maybe not necessarily a living organism, but I could see
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Speaker 1: how someone would characterize it as such. I like that.
1:03
Speaker 1: It's good intro. Yeah, that's what I got. Uh so, Yes,
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Speaker 1: tidal ocean currents, well, not tidal, that's part of the
1:11
Speaker 1: ocean currents. It's a type of current. It's under the
1:14
Speaker 1: current umbrella. I've misspoken the first ten seconds. I think
1:17
Speaker 1: it's funny that in this article the word current refers
1:21
Speaker 1: to the motion of water when speaking of water? Is
1:26
Speaker 1: that what it says when speaking of water, the word
1:30
Speaker 1: current refers to the motion of the water. Yeah, it
1:33
Speaker 1: was a little clumsy Miriam's defines. Yeah, uh, well, this
1:39
Speaker 1: is about ocean currents. Are all kinds of currents, river currents, Yeah,
1:43
Speaker 1: you know, there's currents in marshes and swamps and currents
1:46
Speaker 1: all over the place. But this is about ocean currents. Yeah,
1:50
Speaker 1: as long as water is not stagnant, there's currents present.
1:53
Speaker 1: And if it's stagnant, it's bad news Jack mosquitoes disease. Sure,
1:58
Speaker 1: But then again, you can make the case that if
2:00
Speaker 1: it's not stagnant, if if there's a current, it'll carry
2:03
Speaker 1: your car away in the blink of an eye. I
2:06
Speaker 1: don't even think about it. Boy, did you see the
2:08
Speaker 1: photos of the Downtown Connector the other day in Atlanta
2:11
Speaker 1: when it flooded. Apparently the storm drains backed up in
2:16
Speaker 1: the downtown Connector of Atlanta was a lake. Wow, Like
2:20
Speaker 1: it literally stopped traffic. I can believe that. Yeah, people
2:24
Speaker 1: in Atlanta don't know how to drive in the rain
2:26
Speaker 1: to begin with. Oh, I don't know about that really. Yeah,
2:31
Speaker 1: that's all we do was driving the rain man. People
2:33
Speaker 1: in l A don't have to driving the rain. Seems
2:35
Speaker 1: to me like everybody's brain just drops a couple of
2:38
Speaker 1: years when rain starts, and everyone starts like bumping into
2:41
Speaker 1: everybody else and like driving it two miles an hour,
2:44
Speaker 1: and you just like pedal to the metal. What's different
2:48
Speaker 1: all the time. I got good tires. Yeah, Look, because
2:52
Speaker 1: you liked our stores, right, I don't like tip stores,
2:56
Speaker 1: but I'm willing to spend time there to get good
2:59
Speaker 1: tires that move water away from my car so I
3:04
Speaker 1: can if I have really fast no matter what the weather,
3:07
Speaker 1: you should start your I want to point out. Jerry
3:10
Speaker 1: just sighed heavily at this tangent. I think your retirement
3:15
Speaker 1: business should be Josh's tire house. Yeah, and then have
3:19
Speaker 1: a really sweet setup. Would be like fine tires. Just
3:21
Speaker 1: here's like no place else on earth. Oh yeah, you
3:24
Speaker 1: got WiFi. You got a coffee machine? Well there's well no,
3:28
Speaker 1: I mean a baristah, like a you know, a little
3:31
Speaker 1: mini Starbucks right there in your tire shop. Games have
3:34
Speaker 1: icebreakers meet and greets. Yeah, I could serve icebreakers come
3:38
Speaker 1: to you get have tinder Tinder day. Okay, Well, I
3:42
Speaker 1: don't know a Roman therapy would be good to be
3:46
Speaker 1: a big one massage. Yeah, alright, let's my's my plan
3:50
Speaker 1: b all right, Josh's tire warehouse and pourium, I think
3:54
Speaker 1: is what we came up with. Josh's big house of
3:56
Speaker 1: tires or house with big tires. Okay, so ocean currents
4:01
Speaker 1: we're back to it. So um. One of the things
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Speaker 1: that I did not realize, Chuck, when researching this is
4:08
Speaker 1: that ocean currents they're they're old, but they aren't permanent.
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Speaker 1: They haven't always been around. Currents change, you know. Some
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Speaker 1: currents have been at it for thousands and thousands of years.
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Speaker 1: Other currents change months a month, very fickle in some cases.
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Speaker 1: But there are some really ancient currents, some ancient ocean
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Speaker 1: currents out there that are um very old and have
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Speaker 1: been this way since say, like um, like the Gulf
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Speaker 1: Stream has been around for about five million years, ever
4:40
Speaker 1: since the Isthmus of Panama. Pretty cool stuff, huh. Yeah.
4:45
Speaker 1: I think what I found the most interesting was that
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Speaker 1: ocean currents they have a purpose. You know, it's not
4:53
Speaker 1: just like water moving around willy nilly. You know. If
4:56
Speaker 1: it wasn't for ocean currents, there would be no life
4:58
Speaker 1: in Antarctica. Right, well, maybe not all of Antarctica, but
5:02
Speaker 1: no ocean marine life. But that's that's an important point. Like,
5:08
Speaker 1: if there's no ocean marine life, then there's no like
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Speaker 1: to say, there's no phytoplankton, there's no phytoplankton, there's no
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Speaker 1: fishies eating the phytoplankton. There's no fishies around to eat
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Speaker 1: the phytoplankton. There's no seals to eat the fishies. If
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Speaker 1: there's no seals, Like, everything finds its support, its basis
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Speaker 1: in the ocean. Life that's all supported by the currents.
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Speaker 1: That's right. So the fact that has purpose, it's very
5:35
Speaker 1: teleological of you, chuck. So let's not put this off anymonger.
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Speaker 1: Let's talk about different types of currents. You can't talk
5:42
Speaker 1: about tire stores anymore. Okay, we're done with the tire stores.
5:46
Speaker 1: Like I started to get nauseated just talking that much
5:48
Speaker 1: about tire stores. Alright, I don't feel good. Well, uh,
5:52
Speaker 1: let's start with surface currents then, but I'll bring you
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Speaker 1: back to the to the ocean earth science, your home
5:58
Speaker 1: earth sciences that you love. Uh. Surface currents occur about
6:03
Speaker 1: three to fo um deep and above. Yeah, they're called
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Speaker 1: surface currents, right, and they're driven by the wind. Yeah,
6:12
Speaker 1: they make up for about ten percent of the ocean.
6:14
Speaker 1: And um, if you've ever gone to the beach, you've
6:17
Speaker 1: seen coastal currents. UM surface currents. There's a couple of types.
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Speaker 1: Coastal is one of them. You see them in action, right,
6:25
Speaker 1: like playing in the sand as a little kid or
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Speaker 1: as an adult. You're you're seeing coastal surface currents at work.
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Speaker 1: So let's step back one more degree. So service currents
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Speaker 1: are created by wave action, that's right. Especially coastal currents
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Speaker 1: are created by wave action, which is created by wind.
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Speaker 1: Waves are created by wind. And you know Buckminster Fuller,
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Speaker 1: the inventor of the geodesic dome, among other great things,
6:53
Speaker 1: he was the person who pointed out that the wind
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Speaker 1: doesn't blow, the wind sucks. It's a good point, right, So,
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Speaker 1: and so if coastal currents begin with waves, waves begin
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Speaker 1: with wind. Wind begins with heat because at the equator
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Speaker 1: you have a lot of sunshine all year round and
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Speaker 1: it's very warm, as anyone who's been near the equator
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Speaker 1: can attest. Um, And that heat heats up air, and
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Speaker 1: as the air heats up, it moves away from the equator.
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Speaker 1: It's like, I gotta go cool off. It moves towards
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Speaker 1: the poles north and south, and as it moves toward
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Speaker 1: the poles, it cools down and turns back around. It's
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Speaker 1: like I need to heat back up at the equator, right.
7:36
Speaker 1: And as a result of this, you have wind. And
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Speaker 1: this wind pushes on the surface of the water, transfer
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Speaker 1: some of its energy in the form of friction to
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Speaker 1: the water surface and creates waves and those waves transfer
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Speaker 1: the energy to shoreline and when they come in at
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Speaker 1: an angle, that's when you get that coastal current. Right. Yeah,
7:54
Speaker 1: Like with you've again, if you ever been to the
7:56
Speaker 1: beach and you see the tide or the waves coming
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Speaker 1: in at that angle, and you see it moving with
8:04
Speaker 1: the beach, Like if you've ever been out playing on
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Speaker 1: like a raft is a little kid, you look up
8:09
Speaker 1: an hour later and your parents are like half a
8:11
Speaker 1: mile down the beach from where you start, right. It's
8:13
Speaker 1: a bit of a panicky situation, it is. And also
8:16
Speaker 1: you're like, what kind of parents do I have that
8:18
Speaker 1: they just let me drift half a mile? Yea, you
8:20
Speaker 1: know they're passed out in the sand at that point.
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Speaker 1: Uh So that is called when when uh, a wave
8:26
Speaker 1: breaks on the beach at that angle, it's gonna pull
8:29
Speaker 1: sediment and sand and water down in what's known as
8:32
Speaker 1: a long shore current. That is, uh it's directed off parallel,
8:36
Speaker 1: also perpendicular, but the parallel movement is the long shore
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Speaker 1: uh current. Yeah. It's like when a wave comes into
8:42
Speaker 1: an angle to the shore, it distributes its energy. Part
8:45
Speaker 1: of it directly on to the shore. Part of it
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Speaker 1: parallels is short and um, that's that long shore current,
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Speaker 1: like you said. And one of the things that it does,
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Speaker 1: you also said, is it takes sand and other stuff
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Speaker 1: and deposits it elsewhere further down and along the way.
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Speaker 1: It creates things like barrier islands and sandbars and all
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Speaker 1: that stuff. And that's ever shifting, ever moving, um, eroding
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Speaker 1: and depositing of sand and sediment and those little underwater
9:14
Speaker 1: and sometimes above water deposits create other types of current,
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Speaker 1: specifically a riptide current. Yeah. Um, that's the longshore drift
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Speaker 1: and um, like if you've ever seen like the beach
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Speaker 1: curve back in pretty hard. The water can't make that
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Speaker 1: turn really, so it's just gonna deposit stuff and sort
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Speaker 1: of drop it off there at the end of that
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Speaker 1: point and it'll build up and what's known as a spit, right,
9:40
Speaker 1: and so all of those, all those obstructions, um, all
9:44
Speaker 1: those deposits form obstructions for waves. When they're going back
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Speaker 1: out once they transfer their energy, they're like, oh, I'm
9:51
Speaker 1: pretty far inland. I need to get back out of
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Speaker 1: the ocean. Yeah, And so it backs up right, and
9:59
Speaker 1: as it does encounters these underwater barriers that it itself
10:03
Speaker 1: have deposited. It's kind of a big ironic moment. And
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Speaker 1: so it can't get back out to see as fast
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Speaker 1: as it wants because it's running into these obstructions. And
10:13
Speaker 1: when there's like a break in the obstruction, like a
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Speaker 1: sandbar or something like that had a break in the sandbar,
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Speaker 1: it provides a natural funnel and that creates a rip
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Speaker 1: tide current. Yeah, like, hey, look at that little narrow channel.
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Speaker 1: I'm gonna take all this water that would normally just
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Speaker 1: flow out nice and easy. I'm gonna send it through there,
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Speaker 1: and I'm gonna grab your little kid and take it
10:34
Speaker 1: taken with me. Right. If this, it creates basically suction.
10:38
Speaker 1: Just like when you open a drain in a bathtub
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Speaker 1: and it starts to drain, it drains pretty quick. Yeah,
10:44
Speaker 1: it's dangerous, Like that's how you drown when you're swimming
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Speaker 1: in the ocean. You hear about strong rip currents and
10:50
Speaker 1: inclement weather and um, it's no joke. Even really good
10:53
Speaker 1: swimmers can get caught in a ripping. Yeah, and it's
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Speaker 1: bad news riptide, very bad news. Um. And then there's
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Speaker 1: some other currents that are created that um don't just
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Speaker 1: occur at the at the shore, but they do. They
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Speaker 1: occur in the ocean and at the shore there's this
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Speaker 1: thing called upwelling. This stuff and upwelling can happen in
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Speaker 1: a few different ways, but as far as the coast
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Speaker 1: is concerned. When wind comes in and it basically blows
11:22
Speaker 1: water away from an area, like from the shore, right,
11:26
Speaker 1: water likes to try to even itself out. So as
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Speaker 1: some water is blown away from the surface, this stuff
11:32
Speaker 1: that's below it, the deeper water will come up and
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Speaker 1: basically replace it, and that's upwelling. Yeah. It's another like
11:40
Speaker 1: what strikes me when you look at wind and all
11:42
Speaker 1: these currents. Everything is circular almost right, so a lot
11:45
Speaker 1: of spinning going on. Yeah, there's a really um distinct
11:49
Speaker 1: relationship between wind and water. It's inseparable, especially when you're
11:53
Speaker 1: talking about global winds and currents together, right, But both
11:58
Speaker 1: of them are broken down to fluid dynamic X and
12:00
Speaker 1: they do form these circles and cycles and clockwise motions
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Speaker 1: and counterclockwise motions depending on where you are in the world. Yeah.
12:07
Speaker 1: And in the case of upwelling and downwelling, it's not
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Speaker 1: a horizontal spin, but it is a vertical um from
12:14
Speaker 1: top to bottom and then from bottom back up to
12:16
Speaker 1: the top. Yeah. And you want to talk about um
12:19
Speaker 1: that was which one. Well, both it's the same pattern
12:24
Speaker 1: from top to bottom and bottom to top with upwelling
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Speaker 1: and down welling. Right. And the whole thing about upwelling
12:29
Speaker 1: and downwelling, whether it's at the shore or in the ocean, um,
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Speaker 1: is that the ocean is kind of It's not like
12:38
Speaker 1: if you take a slice of ocean at the top,
12:40
Speaker 1: you take a slice of ocean at the bottom, very
12:42
Speaker 1: different and you look at them. Yeah, under a microscope
12:45
Speaker 1: or test um for whatever, you know, using some sort
12:48
Speaker 1: of uh, spectroscope, maybe some sort of oscillator, glavin or
12:53
Speaker 1: something like that, or just look at it. Yeah, you're
12:56
Speaker 1: going to find that there's it's like two different types
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Speaker 1: of water. Even though it's from the same part of
13:01
Speaker 1: it's from the same section of ocean, right, And the
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Speaker 1: stuff at the top is going to be very oxygen rich.
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Speaker 1: There's gonna be a lot of life phytoplankton, that kind
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Speaker 1: of stuff, um, but not too many nutrients. The stuff
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Speaker 1: at the bottom is gonna be lousy with C O two. Yeah,
13:18
Speaker 1: very cold and a lot of nutrients. Right. And when
13:22
Speaker 1: both of these things are needed at different spots, So
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Speaker 1: the upwelling and the downwelling creates this kind of gas
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Speaker 1: exchange and nutrient exchange throughout the ocean. And the oxygen
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Speaker 1: at the top when it's deposited down lower thanks to
13:37
Speaker 1: down welling, all of that oxygen circulates downward through the
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Speaker 1: ocean and all the fishies that need oxygen in their
13:43
Speaker 1: gills get to breathe it in, right. Yeah. And with upwelling,
13:47
Speaker 1: like I mentioned earlier in Antarctica, where it's super cold
13:51
Speaker 1: and you would not expect marine life to do so well,
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Speaker 1: it is because of the upwelling that brings the nutrients
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Speaker 1: from the bottom up to the top. And that's iCal
14:00
Speaker 1: and that's called life. And one other really neat thing
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Speaker 1: about upwelling and down welling is um that oxygen that's
14:07
Speaker 1: at the top of the ocean. Were it to just
14:09
Speaker 1: sit there for very long and dissolve, we would have
14:13
Speaker 1: a very big problem because all of that life, once
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Speaker 1: it dies, would decay very quickly up tops. No, it wouldn't,
14:21
Speaker 1: because anaerobic bacteria would begin to thrive and we'd have
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Speaker 1: a over abundance of hydrogen sulfide, which would lead to
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Speaker 1: ocean acidification, which would mean the end of the world. Basically,
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Speaker 1: So that nutrient swap is very important for everybody on
14:36
Speaker 1: the planet. Yeah, and there's this elegant solution to the
14:38
Speaker 1: oceans that happens every day everywhere in the ocean thanks
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Speaker 1: to upwelling and downwelling. All right, well that's a good start,
14:46
Speaker 1: my friend. Um my eyes are not glazed over, actually good,
14:49
Speaker 1: they're sharp, full of life. Um. We will talk after
14:53
Speaker 1: this break about some more surface currents. All right, Josh,
15:17
Speaker 1: there's more than one kind of surface current. We covered
15:19
Speaker 1: the I kind of like that first part, but there's
15:21
Speaker 1: also surface ocean currents. And uh, again, the wind is
15:27
Speaker 1: the big contributor to how these babies form um and specifically,
15:33
Speaker 1: I guess we should talk about the Coriolis effect. Yeah,
15:36
Speaker 1: this is a this is a game changer, as people
15:39
Speaker 1: who read self help books on airplanes would call it. Right, yeah,
15:43
Speaker 1: so um. Again, it all starts with heat, and all
15:46
Speaker 1: that heat is found in its thickest part at the equator.
15:53
Speaker 1: And my brain is broken. So at the equator it's
15:56
Speaker 1: the hottest, right, that's right. And it's also also a
15:59
Speaker 1: spinning fast or the equator than at the poles, right,
16:02
Speaker 1: it is okay, so um, it's the Earth that is yeah,
16:06
Speaker 1: so um. At the equator it's hot, it's spinning faster
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Speaker 1: because of the spin. Because of the heat. The ocean
16:13
Speaker 1: is actually about eight centimeters high higher here than at
16:18
Speaker 1: the rest of the ocean. That's so much higher, So
16:21
Speaker 1: there's a right, it's just enough to make water flow
16:24
Speaker 1: away from the equator. Plus you've got wind that's whipped
16:28
Speaker 1: up because hot air at the equator starts moving northward
16:32
Speaker 1: and cools down and that creates wind. Right, So if
16:36
Speaker 1: the Earth didn't rotate, you would still have these things.
16:39
Speaker 1: But wind would travel in a straight line away from
16:42
Speaker 1: the equator towards the poles, cool down and turn around
16:46
Speaker 1: and come back in a straight line. That's right. But
16:48
Speaker 1: that's not the case. No, it isn't because the Earth
16:51
Speaker 1: does rotate and it produces the Coriolis effect. Yeah, it's
16:54
Speaker 1: like a curve. Basically, it uh curves to the right
16:57
Speaker 1: in the northern hemisphere and to the left in the
16:59
Speaker 1: southern hemisp here. Right, so it makes wind curve and
17:03
Speaker 1: since wind drives surface currents, it makes surface currents curve
17:07
Speaker 1: as well. Right, that's right. So what's really cool is
17:11
Speaker 1: the ocean has its own topography. It's it's definitely not fight.
17:15
Speaker 1: Anybody who's looked at ocean could be like, oh, it's
17:17
Speaker 1: pretty choppy. But if you if you could step back
17:19
Speaker 1: even further and you had the right kind of topographical
17:24
Speaker 1: glasses on, maybe you would see that there's like valleys
17:28
Speaker 1: and ocean and mountains and maybe not mountains, but little
17:31
Speaker 1: tiny hills and valleys in the ocean. So, like I said,
17:35
Speaker 1: it has its own topography. And this is created by
17:38
Speaker 1: those winds that push on the water. And as they're
17:41
Speaker 1: pushing the water up and the Coriolis effect is turning
17:44
Speaker 1: at some water starts to kind of mound. So in
17:48
Speaker 1: some parts of the ocean you have water that forms
17:50
Speaker 1: a mountain that's about like three to six ft tall. Yeah,
17:54
Speaker 1: it doesn't sound intuitive, no water mounding up on itself.
17:59
Speaker 1: You think if it as ye, But there is actually
18:02
Speaker 1: water that's mounded up into little hills, okay. And so
18:06
Speaker 1: that means that gravity wants to push this water downward, right,
18:12
Speaker 1: But it doesn't just go back down the hill, because
18:14
Speaker 1: the Coriolis effect pushes it upward. And the net outcome
18:20
Speaker 1: is that instead the water just says, how about it
18:24
Speaker 1: just go around instead? Yeah, you stay up here on
18:27
Speaker 1: the mound, you stay down here, but I AM going
18:29
Speaker 1: to just go around. And what it does is, since
18:32
Speaker 1: a mound is roughly circular, it creates a current that
18:36
Speaker 1: goes around these things, around these mounds. And there's five
18:39
Speaker 1: major ones in the entire world where you're headed, and
18:42
Speaker 1: they form what are called gyres, that's right, g y R, E, S,
18:46
Speaker 1: and um. They are the North Atlantic, South Atlantic, North Pacific,
18:50
Speaker 1: South Pacific, and then the Indian Ocean has its very
18:53
Speaker 1: own gyre. There are smaller ones around Antarctica, but those
18:57
Speaker 1: are the five major gyres. We about the Gulf Stream earlier.
19:01
Speaker 1: That is a part of the North Atlantic gyre, and
19:05
Speaker 1: it carries times the water of the entire Mississippi River.
19:11
Speaker 1: The Gulf Stream does. Yeah, the Gulf Stream is the
19:14
Speaker 1: hero of all gyres. It is it moves um. Let
19:18
Speaker 1: me see, I've got to find this one because this
19:21
Speaker 1: is so amazing. So the the Gulf Stream, at any
19:25
Speaker 1: given point, it moves water at a rate of fifteen
19:31
Speaker 1: superdomes worth per second. So you remember the superdome in Louisiana. Yes,
19:38
Speaker 1: say you've filled it with water, and then you took
19:42
Speaker 1: copied fourteen more times, so you have fifteen superdomes full
19:46
Speaker 1: of water. That's how much water passes through any given
19:50
Speaker 1: point per second. Okay in the Gulf Stream. All right,
19:55
Speaker 1: that's a lot of water. How many big max is
19:57
Speaker 1: at It's trillions of big max billions and billions served.
20:01
Speaker 1: But the the Gulf Stream itself is actually um. It's
20:05
Speaker 1: technically the western boundary current of the North Atlantic gyre. Yeah,
20:11
Speaker 1: and it's gonna carry warm water. It's it has a
20:13
Speaker 1: big impact in the world. It's gonna carry warm water
20:17
Speaker 1: up north from the Gulf of Mexico. And that's why
20:20
Speaker 1: if you're living on the east coast of Florida, you're
20:23
Speaker 1: gonna have cooler summers and warmer winters. Um. Western Europe
20:27
Speaker 1: is gonna be a lot warmer than other places on
20:29
Speaker 1: its exact same latitude. And this is all because of
20:33
Speaker 1: the Gulf Stream. You can deposit bodies in it if
20:36
Speaker 1: you're dexter, and those things are gonna yep, see a
20:40
Speaker 1: later body. Yeah, it will probably get carried to England
20:43
Speaker 1: and they'll be like blind, me was this? Uh So
20:46
Speaker 1: that's just the Gulf Stream. There's actually at least four
20:49
Speaker 1: major currents that form the boundary currents of the North
20:52
Speaker 1: Atlantic Gyre, and the North Atlantic Gire is just one.
20:56
Speaker 1: We've also talked about jarres before with the Great Pacific
20:58
Speaker 1: Garbage Patch. Yeah we covered did we do waves or
21:01
Speaker 1: did we just do We did rogue waves too, but
21:05
Speaker 1: we covered waves and surfing. Okay, ye remember that. Um
21:08
Speaker 1: But these these boundary currents are created again in part
21:13
Speaker 1: by the the winds flowing away from the um equator,
21:18
Speaker 1: the Coriolis effect, turning the waves and the mounds of
21:21
Speaker 1: water circulating the waves in around them. So you've got
21:26
Speaker 1: these like just clockwise or counterclockwise depending on which hemisphere
21:29
Speaker 1: you are, currents that are just massive that move water
21:33
Speaker 1: around and again they cycle nutrients. Like you said, they
21:37
Speaker 1: affect the weather because they deposit warm water from the
21:42
Speaker 1: south up to all the way up to England apparently.
21:46
Speaker 1: Um so you know, England is on the same latitude
21:52
Speaker 1: as like, um, some glacial parts of Canada. Yeah, that
21:57
Speaker 1: makes sense. But they're they're winners, are like nothing into that,
22:00
Speaker 1: you know, Thank you ocean. Same thing as a Bermuda
22:04
Speaker 1: is very temperate, has very nice climate, and it's on
22:07
Speaker 1: the same latitude as North Carolina, which is you know,
22:11
Speaker 1: it can get kind of cold there. That's all thanks
22:14
Speaker 1: to the Gulf Stream. Thank you Gulf Stream. And if
22:17
Speaker 1: you want to thank the Gulf Stream, Chuck, you can
22:19
Speaker 1: thank Ben Franklin because he's the one who named it. Yeah.
22:23
Speaker 1: As the first Postmaster General of the United States, he
22:27
Speaker 1: wanted to figure out why Mayo took so many more
22:30
Speaker 1: weeks longer to get from England to the US than
22:34
Speaker 1: it did from the US to England, because they're they're
22:36
Speaker 1: going against traffic exactly. But he didn't know that, and
22:39
Speaker 1: he found out and he took some measurements and roughly
22:42
Speaker 1: charted the Gulf Stream back in the eighteenth century. He
22:46
Speaker 1: was a smart dude, he really was. That was pretty amazing.
22:49
Speaker 1: I didn't know he dabbled in oceanography. But again, the
22:52
Speaker 1: Gulf stream amazing, and it's just one boundary current of
22:56
Speaker 1: one major gyre. Yeah, it's kind of a hypnotic. If
23:00
Speaker 1: you look at these motion maps of global motion maps
23:03
Speaker 1: of like trade winds and ocean currents. Yeah, I could
23:06
Speaker 1: watch those videos all day. It's just stuff spinning around
23:09
Speaker 1: and like traveling around, and it's really it's soothing, and
23:13
Speaker 1: especially when they do like heat gradients or topographical gradients,
23:17
Speaker 1: so it's really colorful too, and it's ever shifting. You
23:20
Speaker 1: can just get a little jewel out of the corner
23:22
Speaker 1: of my mouth when I watched though, it's about as
23:24
Speaker 1: good as watching Phantasia. Um. There's one other thing we
23:27
Speaker 1: should say about those surface currents is they drag on
23:30
Speaker 1: the water below them, right, So the wind is transferring
23:34
Speaker 1: its energy to the surface of the water. Yeah, and
23:38
Speaker 1: it drags a little bit less is the deeper you go. Right.
23:40
Speaker 1: Apparently though, the current that the motion of water, um
23:46
Speaker 1: usually goes in opposition to the motion of wind. So
23:50
Speaker 1: what you end up having if you could take a
23:52
Speaker 1: column slice from top to bottom of the ocean, you
23:56
Speaker 1: would find that the water ultimately is making a very
23:59
Speaker 1: long down words spiral. Yeah. So, and that's called the
24:02
Speaker 1: ekmun spiral. Yeah, that there's a graphic of that that
24:06
Speaker 1: looks pretty neat as well, pretty neat again, mesmerizing stuff,
24:10
Speaker 1: so chuck um. After this, we will talk about the
24:14
Speaker 1: global conveyor belt. It's my favorite part, I think, all right,
24:36
Speaker 1: my favorite part of ocean currency. Ocean currents, the deep
24:43
Speaker 1: ocean current a k a. The Global conveyor belt is
24:46
Speaker 1: fascinating to me. Um. If you're talking about this is
24:50
Speaker 1: about if the surface currents are about ten about of
24:54
Speaker 1: the ocean's water, uh is part of the deep ocean current,
24:57
Speaker 1: and we can't see it, um because we're up here
25:01
Speaker 1: on Earth and we are not deep under the water.
25:04
Speaker 1: It's invisible to us. But um, it circles the globe
25:07
Speaker 1: at a four sixteen times is strong as all of
25:11
Speaker 1: the world's rivers combined, which is again still not as
25:15
Speaker 1: much as the the the Gulf Stream. Still pretty impressive.
25:20
Speaker 1: It's pretty impressive, um, but slow so like water. It
25:25
Speaker 1: moves super water a few centimeters a second, whereas the
25:28
Speaker 1: Gulf stream moves waters at like a couple dred centimeters
25:31
Speaker 1: a second. Yeah, I think the conveyor belt, they said,
25:34
Speaker 1: like one patch will take a thousand years to completely Yeah,
25:39
Speaker 1: around yeah, the circuit. Yeah, and it takes ten years
25:42
Speaker 1: for water to make a full circuit on the North
25:45
Speaker 1: Atlantic gyre. Yeah, so ten years and then a thousand years. Yeah. Um.
25:51
Speaker 1: So the global conveyor belt, it is uh driven by density,
25:55
Speaker 1: which I think is pretty interesting. Um. Yeah, because up
25:58
Speaker 1: to this point it's all been driven by wind, which
26:00
Speaker 1: is ultimately driven by heat. This is also driven by
26:03
Speaker 1: heat in a way, but in a completely different way. Yeah,
26:06
Speaker 1: heat and salt um thermohaline circulation thermo being heat and
26:11
Speaker 1: haling being salt. Uh. Warm water holds less salt. So
26:16
Speaker 1: what happens is like let's say you're in the Antarctic
26:20
Speaker 1: and water freezes to form an iceberg or water evaporates.
26:26
Speaker 1: Either way, salt is not going to be a part
26:28
Speaker 1: of that equation. Now the salt is left behind as
26:30
Speaker 1: the water freezes, and you know, icebergs on salt salty
26:33
Speaker 1: their fresh water. Yeah, so the salt is left behind.
26:36
Speaker 1: It's got to go somewhere. Um, it is going to
26:39
Speaker 1: be very dense at that point. So it is going
26:42
Speaker 1: to be cold and dense and sink to the ocean floor.
26:46
Speaker 1: So remember back on talking about right, and we were
26:49
Speaker 1: talking about um, coastal um coastal currents and upwelling and
26:54
Speaker 1: down welling. Yeah, this plays apart. When water sinks, other
26:57
Speaker 1: water moves in to replace it. And so what starts
27:01
Speaker 1: off here? And this actually I think starts around the
27:03
Speaker 1: North Pole definitely in the North Atlantic. Um, as that
27:07
Speaker 1: water sinks and moves downward, it creates it starts this
27:10
Speaker 1: current that goes all the way around the world and
27:12
Speaker 1: again takes a thousand years to complete. Yeah, it just
27:16
Speaker 1: kick starts at basically. And um it's called the conveyor belt,
27:19
Speaker 1: I think because it never stops moving and it's super slow. Yeah,
27:23
Speaker 1: I kept getting that remember that, um whatever that Bugs
27:27
Speaker 1: Bunny assembly line song? Like it was always the same,
27:31
Speaker 1: Like do you remember that? I can't remember it either.
27:33
Speaker 1: Now I have our theme song in my head. I'm
27:35
Speaker 1: trying to think about it. But there's like anytime Bugs
27:37
Speaker 1: Bunny messed around on a conveyor belt or something, they
27:39
Speaker 1: use the same like composition. I'll try to find it. So, uh,
27:46
Speaker 1: once this water hits Antarctica, basically the same thing happens
27:49
Speaker 1: all over again. The cold water is gonna split. Some
27:53
Speaker 1: of it heads to the Indian Ocean, some heads to
27:56
Speaker 1: the Pacific, and this upwelling and downwelling, the cycle just
27:59
Speaker 1: start all over again, yeah, is it? As it moves
28:01
Speaker 1: closer to like the Indian Ocean and the Pacific, it
28:04
Speaker 1: gets closer to the equator, the water starts to warm up,
28:08
Speaker 1: it loses some of its salinity, it starts to thin
28:11
Speaker 1: out a little bit, and so it rises. And when
28:13
Speaker 1: it does, it takes all those nutrients and all that
28:16
Speaker 1: CEO two up with it. And it's very much like
28:20
Speaker 1: the gas exchange that occurs in the human cardio pulmonary system. Right. Yeah,
28:24
Speaker 1: it's not homeostasis, but it almost feels like that if
28:28
Speaker 1: you took the whole system overall. Yeah, it's homeostatic for sure,
28:32
Speaker 1: but it's like that by this exchange, this transfer from
28:35
Speaker 1: one part to another, from the deep ocean to the surface. UM.
28:39
Speaker 1: And and this this as it reaches the surface and
28:43
Speaker 1: it depletes its nutrients, it's carried back around UM. It
28:47
Speaker 1: basically tries to go up hits Um Alaska, Russia, Asia,
28:53
Speaker 1: North Asia, Northeast Asia, and UM turns back around and
28:58
Speaker 1: goes ends up finally back in the North Atlantic, up
29:02
Speaker 1: near the North Pole and gets cold and starts all
29:04
Speaker 1: over right, And by the time it gets there, it's
29:06
Speaker 1: basically nutrient depleted and it sinks and it starts to
29:10
Speaker 1: recharge again. That's right. And that just like blood in
29:14
Speaker 1: your in your cardio pulmonary system, it gets depleted, it
29:18
Speaker 1: ends up going past the lungs, it transfers out CEO two,
29:21
Speaker 1: it gets in oxygen. This is just the opposite. This
29:24
Speaker 1: is transferring out oxygen and gaining CEO two and nutrients.
29:27
Speaker 1: That's a good way to feel connected to the Earth.
29:29
Speaker 1: When you start looking at things like that, you know,
29:32
Speaker 1: it's not so different. It's I mean, we're all connected, man. Uh.
29:40
Speaker 1: And again there's a big nutrients swap meat happening as
29:44
Speaker 1: well with the conveyor belt like we're talking about, and
29:48
Speaker 1: basically kind of has the same effect as those surface
29:51
Speaker 1: uh currents do ye as far as exchanging the the
29:56
Speaker 1: oxygen and the CEO two and nutrients and just moving
29:59
Speaker 1: everything where needs to be. UM. I thought this was
30:02
Speaker 1: pretty cool in this article, UM, the it talks about
30:06
Speaker 1: there's also a density driven a thermohalen current in the
30:10
Speaker 1: Mediterranean because the Mediterranean is apparently saltier than the Atlantic,
30:15
Speaker 1: and as a result, this gradient. Anytime you have a
30:18
Speaker 1: difference in something, whether it's height, temperature, um, salinity, density.
30:24
Speaker 1: Homeostasis is the ultimate goal, so it's going to try
30:27
Speaker 1: to go towards the middle, from higher to lower. And
30:30
Speaker 1: this is the same thing. So it creates that oceanic current.
30:33
Speaker 1: And apparently in World War two, subs would um run
30:38
Speaker 1: silent by going in and out of the Mediterranean without
30:41
Speaker 1: their engines on, just using that currently, so they would
30:48
Speaker 1: run deep, run silent, run deep exactly. That's frightening. Alright,
30:53
Speaker 1: are we a title currents? You don't have to be frightened.
30:55
Speaker 1: It was years ago. Yeah, we're a title current that
30:59
Speaker 1: they still do that. Now there's no submarines anymore. We
31:04
Speaker 1: haven't been at war for years. They retired all the submarines. UM. Alright.
31:09
Speaker 1: Tidal currents are generated by the tides. UM. We did
31:13
Speaker 1: talk about UM, like we said, I think in the
31:16
Speaker 1: rogue waves and surfing about tides and waves and UM.
31:22
Speaker 1: The gravitational pull of the moon and the Sun, but
31:24
Speaker 1: more of the Moon because the Moon is closer, is
31:27
Speaker 1: what's gonna cause that bulge on the sides, and it's
31:30
Speaker 1: gonna drive the water level UM at that bulge. Basically,
31:36
Speaker 1: it's going to decrease, it's going to increase where it's
31:39
Speaker 1: a line with the moon and decrease at the halfway
31:42
Speaker 1: point between those two places. And so and it's always
31:45
Speaker 1: changing because the moon, the position of the Moon and
31:48
Speaker 1: the Sun and the Earth are always changing, but they
31:51
Speaker 1: change in a very predictable manner, so we can predict
31:54
Speaker 1: when the tides happen. But if you just took a
31:56
Speaker 1: snapshot at any given point of the title effect, right,
32:02
Speaker 1: and if you imagine that the Moon is on one side,
32:06
Speaker 1: the Sun is on one side, and the Earth is
32:08
Speaker 1: on the middle. The world's oceans around the Earth stretch
32:13
Speaker 1: out on the sides and um because of that gravitational pull,
32:19
Speaker 1: and just imagine that it's always like that. It's always
32:22
Speaker 1: just this elliptical oval shape the world's oceans are and
32:26
Speaker 1: then the Earth, the dry Earth, is spinning within that
32:30
Speaker 1: and so the land masses on the Earth are always
32:33
Speaker 1: coming in and out of that bulge, and so they're
32:36
Speaker 1: going from higher to lower tide. It's kind of it
32:39
Speaker 1: just makes it easier for me, rather than to think
32:41
Speaker 1: of the oceans moving around the Earth, to think of
32:44
Speaker 1: the Earth spinning within the ocean, and that causes the
32:47
Speaker 1: change and tides that does something for you, does it
32:51
Speaker 1: all the way? Uh? And these are different than the
32:54
Speaker 1: other currents we talked about because they're not it's not
32:56
Speaker 1: a continuous stream and they switch directs. That's the high
33:00
Speaker 1: tide and low tide and um, it doesn't impact like
33:05
Speaker 1: the ocean current that much. It's shoreline stuff. Yeah, but
33:09
Speaker 1: it's pretty important. I mean, like fish, fishes lay eggs,
33:13
Speaker 1: and uh, low tide will pull those eggs out into
33:17
Speaker 1: the open ocean and those fish will they'll hatch. It
33:21
Speaker 1: also brings food in from the ocean into like marshland
33:26
Speaker 1: and that kind of stuff, or washes up jellyfish and
33:29
Speaker 1: to delight the children on the beach, yes, but don't
33:32
Speaker 1: touch them, you can just look. Uh. And when the
33:36
Speaker 1: tide is rising, um, that flow is directed towards the store.
33:40
Speaker 1: That's called the flood current. I've heard about that flood
33:42
Speaker 1: and the EBB. And the EBB is when it's directed
33:45
Speaker 1: back out to sea. And that makes it all very predictable.
33:48
Speaker 1: Like you said, we can go to the beach and
33:51
Speaker 1: listen to the tide report. It's also a very relaxing
33:54
Speaker 1: thing to do. Oh yeah, oh yeah, I listen to that.
33:57
Speaker 1: Like the a m like fishing and sharks and title reports. Yeah,
34:02
Speaker 1: it's very relaxing for me. I like it. I remember
34:04
Speaker 1: growing up listening to like grain future reports and hog
34:07
Speaker 1: reports or stuff like that. Pork futures, um chuck, just
34:12
Speaker 1: a couple more things. So, like, there are plenty of
34:15
Speaker 1: other currents, and there's also plenty of other wind patterns
34:19
Speaker 1: that drive these currents. They do things like create the
34:21
Speaker 1: l Nino, which basically takes weather, thunderstorms and stuff around
34:26
Speaker 1: the equator and moves them in different places that were
34:30
Speaker 1: not used to, which can lead to droughts and floods
34:32
Speaker 1: depending on where you are. And then also there's a
34:35
Speaker 1: lot of concern among scientists who are who know about
34:40
Speaker 1: this kind of stuff that um changes. Climate change is
34:45
Speaker 1: going to is going to ultimately and negatively affect the
34:49
Speaker 1: global conveyor belt because as um as the earth warms
34:54
Speaker 1: up uh more and more icebergs are gonna melt, creating
34:58
Speaker 1: much less salinity. And since the water will be less
35:02
Speaker 1: saline um and warmer, it's gonna sink less. And so
35:08
Speaker 1: that global conveyor belt that relies on cold, dense salty
35:12
Speaker 1: water to sink to get it started, is going to slow,
35:16
Speaker 1: and that could be bad because remember it's all that's
35:19
Speaker 1: the global nutrient exchange. Would no, because then the phytoplankton dies.
35:24
Speaker 1: And again when the phytoplankton dies, the fishes die, the
35:28
Speaker 1: seals die, polar bears are upset. Well, the poor seals die.
35:31
Speaker 1: Either way, it is very sad. Yeah, do you got
35:37
Speaker 1: anything else? No, that's it. That's ocean currents. Uh. If
35:41
Speaker 1: you want to know more about ocean currents, you can
35:44
Speaker 1: type those words into the search bart how stuff works
35:46
Speaker 1: dot com. And since I said search bars, time for
35:49
Speaker 1: a listener mail. I'm gonna call this French speaker. Um
35:55
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36:04
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36:07
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Speaker 1: I'm sorry, exchange, I could give you pickup lines in
37:12
Speaker 1: French voir or what? Or what Danielle? I have to say,
37:20
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