February 18, 2021 • 36 mins
Geologists and biologists have recently realized that the planet’s oceans and coasts are littered with a unique type of ecosystem called blue holes, submerged sinkholes that were once dry caves. They are turning out to be weird and amazing places.
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Episode Transcript
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Speaker 1 (00:01):
Welcome to Stuff you Should Know, a production of I
Heart Radio. Hey you' welcome to the podcast. I'm Josh Clark,
and there's Charles W Chuck Bryan over there. Jerry's hovering
about and this is Stuff you should Know, another jazzy
(00:21):
Earth Science edition. Chuck. Yeah, and this is like, I
know we covered this head of an Internet Roundup? Did we?
I don't think we covered. I mean, we've done a
lot of cave stuff. We did sinkholes, cave dwellers, caving,
cave diving, peleology, and cave diving. So which one like
(00:43):
it could have come up in cave diving? I think maybe?
But I feel like I remember showing a picture. I'm
feeling Internet Roundup. Okay, yeah, we've been. That's kind of
funny because this, then is the second thing we've done
that we already did on Internet Roundup and then forgot about.
That's right, that's a trend. We're trending. Um. But the
cool thing about this one, Chuck, is that, like these
(01:05):
things that we're going to talk about today, blue holes
are so um new scientifically speaking, they're so unexplored um
that there's a lot we can get wrong, and no
one will know for like ten or fifteen years. Perfect.
We'll be done by then, isn't that great? Yeah, yeah,
we'll be We'll be sipping my ties on the beach
earning by then. Off German bearer bonds. What is that
(01:29):
trading places? No, that's a die Hard Okay, I think
that was a mash up. Oh yeah, that's funny how
things just kind of invade your subconscious like that. Well,
I mean trading places. They definitely were sipping drinks on
the beach, which did not happen in die Hard. No,
but he says it's like something like that. Yeah. Yeah,
(01:51):
he says, by the time the FBI figures out what's
going on, will be sitting on the beach. I think
he says sipping my ties earning. Does he say like
in trading places? That's right? Yeah, but he like breaks
the fourth wall and stairs right at the camera. We
need deliver. That would be great. So um, obviously, as
everyone's picked up by now, we're talking about blue holes
(02:13):
and if you don't know what a blue hole is,
I feel like this is definitely one of those ones
where we need to define it rather than just start
talking about it out of the gate. Uh, define what
it looks like or or the reveal of what it is. Okay, yeah,
we'll define what it looks like first. How about that?
All right, Well, it looks like a blue hole in
(02:34):
the ocean, like, you know, there's ocean, and then all
of a sudden, it's like, wait a minute, there's a
you know, sometimes they're pretty circular, like almost exactly circular,
and sometimes they're oddly shaped, but it's definitely like a
different color. And what it looks like from a bird's
eye view is like, well, hey, that looks like it
might be deeper right there, and it is. Yeah, and
(02:58):
it's a much much darker shade of blue than the
surrounding areas because it's a deep, deep hole in the
sea floor and the stuff around it is usually far
shallower comparatively speaking, so usually the area around is like
a much nicer, kind of lighter blue green, clearish color.
And then this is like this really stark, dark blue
(03:19):
hole again in the middle of the sea floor, and um,
it's a they're really popular diving spots. You have to
be a really good diver, as we'll see, to dive
on a blue hole, and they're also have long for centuries. Um,
been known locally um as really great fishing spots, both
commercially and for sport fishing. But the thing is, it's
(03:41):
like it's starting to become clear to geologists and biologists
that these things are kind of dotted all over the world.
There's some out to see, there's some that are actually landlocked, um,
but that they share some commonalities, and that these things,
these blue holes, submerged holes in the ground or the
sea floor are some of the weirdest, um most amazing
(04:04):
environments that that are exist on Earth right now. Yeah,
and you know, we should probably say that fishermen everywhere
are probably still mad at Jacques Cousteau who in nineteen
seventy two put the Great Blue Hole, which is one
particularly striking blue hole off the coast of Belize. He
put that on the map in nineteen seventy two on
(04:27):
a show that I used to love to watch, The
Undersea World of Jacques Gusta. Did you watch that? No,
I saw The Life Aquatic with Steve Zoo though so
close enough. Yeah, I was. I'm not sure what channel
it came on, or that was in reruns or if
I was watching it live, but it was sort of
like you know that in Mutual Omaha's Wild Kingdom were
(04:48):
the two big nature shows for me growing up as
far as turning me onto to all this stuff, right
the uh. I think the show ran from nineteen sixty
six to seventy six, so it's entirely possible you were
watching it live was a youngster. Probably reruns, yeah, but still,
I mean, I'm sure it immediately went in to reruns.
It was wildly popular. And that particular episode, if you're interested,
(05:09):
was Secrets of the Sunken Caves. But yeah, he put
this thing on the map, like, not literally, it was
on maps already, but he introduced it to the rest
of the world. UM. And the Great Blue Hole, as
that one in Belize that he covered is called UM
is on basically every serious scuba diver's bucket list to dive.
It's just it's just one of those places you have
(05:32):
to dive before you die. Hopefully you don't die while
you're diving on it, but it does happen sometimes it does. Uh.
And blue holes are basically uh. You know, I mentioned
sink or episode on sinkholes at the beginning. That was
a bit of an easter egg, because that's really all
they are is underwater sinkholes. It's a feature of what's
known as a karst system k a r st um
(05:56):
where you have this porous limestone making up the bedrock,
which you know leads to a lot of things. It's porous,
so it uh sentiment it like it wears away and
the road's kind of easier, I think than other kinds
of bedrock. That's where if you listen to any of
the caving episodes, is where you're gonna get some some
of these great stalactites and stalagmites because that acid rain
(06:19):
drips down and wears away that limestone, and you know,
it forms little icicles from the top and then when
it hits the bottom it forms reverse icicles on the floor.
And some of these blue holes have these stalactites and
stalagmites because they used to be you know, they used
to be land, right, they used to be dry caves.
(06:39):
Like that's the thing. Once they found stalactites and slag
mites um in these blue holes kind of give up
to see they're like, okay, this had to have been
above dry land because the dripping effect of water coming
from the top and then dripping down to the bottom.
It's kind of lost in the translation. When the thing
is already submerged in water, it has to be dry,
(07:00):
you know what I'm saying. Else not really No, I
think it just kind of goes every which way rather
than straight down. So yeah, when they when they started
finding these um collectively stalactites which come down from the
ceiling and stalagmites which come up from the floor. They're
collectively called spelio theems which we've talked about in plenty
of other episodes, when they started finding speleothems in in
(07:22):
these um blue holes, they're like, these were once on
dry land, which is pretty cool. But it also makes
sense too that these are just caves that formed at
some point in the great, great distant past on on
unearthed UM. I mean, where else are they going to form?
You know? Um? And it also makes sense that as
a cavern formed through the same process that forms spelio
(07:45):
theems um. It's just the water kind of carves out
a hole in the limestone, it dissolves it, and then
it gets bigger and bigger over time, and then all
of a sudden you have a cavern that the roof
of that area is not supported like it is surrounding
and so it's a vent going to clap in, whether
it's on dry land and as a sinkhole, or if
it's on dry land, and then that eventually becomes submerged
(08:06):
by water, you have a blue hole. So it's just
a sinkhole that's now out to see because the sea
level rise. Basically, Yeah, and one of the cool things
about the Great Blue Hole is when they started looking
at these stalactites and stalagmites, are like, well, some of
these look like you would expect because when things dripped,
they dripped straight down or build straight up. But some
(08:27):
of these are angled, sometimes up to twelve degrees, and
they're like, that's pretty interesting. So what it probably means
is that this thing formed over many, many many years
and the Earth's tectonic plates started shifting and so they
started dripping at different angles. So you've got this really
cool effect that happens where you have these you know, Uh,
(08:49):
it's something that you wouldn't see normally in a cave. Basically,
So if a couple of years ago, uh nat g
O and Richard Branson did an expedition where they were
are basically tried to map the Great Blue Hole three
D map. It and they went down there, and they
they went deeper than I think had been before in
a in a submarine like that, and found a bunch
(09:12):
of stuff. Um. They found that it was filling up
very slowly. I think they likened it to like an
underwater hour glass. Um, it's very slowly, so it's not
like it's going to be full anytime soon. Uh. They
found a two leader bottle of coke, uh, go pro
camera and some some dead people, some dead humans, a
(09:33):
lot of dead animals, but some dead humans as well. Yeah.
So the blue hole um has claimed at least three
lives that we know of on record right, um, which
is actually kind of a low ratio compared to some
other blue holes out there. UM. But they are still
down there, and like you said, two of them were
found by Branson and the nat GEO crew and they
(09:54):
came back and told the authorities and Belize exactly where
they were. Um. And they also apparently said, but look,
it's really quiet down there. It's really like a RESTful place,
like you could do a lot worse for a final
resting place than the bottom of the blue hole in Belize.
And I guess the authorities, I don't know if they
consulted with the families or what. But I was made
(10:15):
to think by some of the stuff I read that
the authorities in Belize said, you know, let's just leave
them down there and that will be their final resting place,
which sounds a little morbid from the outside, but that's
actually kind of customary when it comes to cave diving
in particular. I think we talked about that a little
bit in Caved the cave Diving episode, Yeah, for sure. Um.
(10:37):
And the cool thing about the Great Blue Hole is
that at one point it was it was in the jungle. Yeah,
so that would make it a different kind of blue hole,
which is still technically a blue hole, but it's called
the uh Ankielin I'm pretty sure that's right pool, which
is a blue hole, but it's landlocked, so like the
(10:57):
rim is exposed to dry air. It's not underwater like
on the sea floor because the sea levels just aren't
that high. And one of the interesting things about the
Great Blue Hole in Belize is it was at some
point because sea levels lowered so so dramatically um during
the last interglacial maximum about twenty six thousand years ago,
(11:19):
that that a significant portion of this vertical cave which
is now the Great Blue Hole in Belize was dry.
It was just totally dry, Like you could walk around
the top of the rim because it was no longer underwater.
You could jump in. You would die, but you could
jump in, and you would go all the way down
and then maybe at about the bottom, say twenty meters
(11:41):
of the cave, you would finally hit seawater. So over time,
the seawater levels have risen from the last time the
Earth was in a ice age UM, and the seawaters,
the sea levels have risen so much that now the
cave is totally submerged and is actually um many meters
under the surface of the sea because of sea level rise. Yeah,
(12:06):
and there's there's some really cool things you can learn from, uh,
from studying these blue holes, and maybe we should take
a break and learn about those right after this. Alright,
(12:36):
So there's a couple of really cool things that you
can learn by studying blue holes. UM. One of them is, uh,
you can look at this sediment and you can basically
kind of get a snapshot of of ancient weather patterns. UM.
I think when they when Branson and the gang went
down to the Great Blue Hole, they found a lot
(12:58):
of sediment where it's sort of indicated that UM in
different areas that indicated that that perhaps the Mayan Empire
had several severe hurricanes and maybe had something to do
with them not being around for much longer. Yeah, because
so the these UM these blue holes are basically at
a certain level cut off from the ocean above them,
(13:22):
like there's a point where there's no currents any longer,
whether the waves can affect it um, where there's no
oxygen dissolving past a certain boundary that we'll talk about
in a second, and so beneath a certain depth, they're
just like this, this perfect record of the Earth's geological history,
(13:44):
frozen and sequestered from everything else. So if you go
down there and this is the kind of the trend
that they're starting to figure out that these are the
expeditions are trying to launch and start taking samples of
the sediment, you can get like a really good picture
of Earth's say like her a cane passed or drought passed.
Apparently UM when when there's spikes and iron content, they
(14:05):
take that as UM from dust storms from Africa, which
which UM says that there's probably severe drought around the
world that year. So there's all of this information you
can glean that's just trapped and locked in the bottom
of these these great blue holes because they're so deep
and so remote and so unaffected by the world above them.
I just think that's amazing. It's super cool. Uh. The
(14:28):
other cool thing you can learn about is um sea
level rise over the years. We don't have the clearest
picture in science of anciency levels and when they were,
you know, like exact levels of when there were glacial
periods and interglacial periods and the rising and falling of
the seas. But if you go down there and you
radio carbon date these stalactites and stalagmites, you can compare
(14:51):
them to the relative depths of the whole cave system,
and then you can basically say when was their air here,
when was there water here, and get a pretty, you know,
at least a much better picture of what the sea
levels used to look like. Yeah, and they figured out
that the cave itself was formed um between about a
hundred and fifty three thousand years ago to about fifteen
(15:12):
thousand years ago. There are four major dry periods where
the cave was exposed during that time, and I don't
know if they figured out from the um the Great
Blue Hole itself or if they just already knew this,
But apparently in the past the sea level has risen
really quickly a couple of different times UM. I think
(15:33):
eleven thousand years ago and eight thousand years ago. Over
the course of less than a hundred and fifty years,
it rose twenty five ft and then again twenty one
ft in less than less than two centuries, which is
a really significant rise UM. And having information like that
is really vital to kind of placing our current sea
(15:54):
level rise and experience of climate change in context in
this greater context of Earth's history and possibly it's normal
rhythms or what's abnormal. So to be able to understand
that because of the kind of the record that's kept
in the blue holes is extremely helpful. Yeah. And I
think the usual level of sea rises about a meter
(16:16):
every century, so a spike of twenty four and twenty
ft is really really big. It's I mean, you could
basically watch it happening. You know, it's start to come
up around your ankles if you stood in there the
same place long enough. Another cool thing about blue holes,
and in particularly the Great blue hole is that there
(16:36):
is a layer of hydrogen sulfide that basically acts like
a blanket, uh, And there are different depths depending on
which blue hole you're talking about, But it's just a
real concentrated layer of hydrogen sulfide. That is, it's a
bike product of decaying plant material, and it's kind of stinky.
It's kind of that sulfury eggy smell that you might
(16:57):
smell sometimes, and it's uh, really really clear water below
in this area it is really brown and kind of gross,
and then you know it's it's so far down it
doesn't look brown and gross from the top. It still
looks nice and blue. But it's really a separation point
where above it you have life and below it there's
no oxygen getting through, so you have no life now.
(17:20):
And I saw it described as like kind of hazy brown,
kind of cobwebby layer. I think in the Great Blue
Hole in particular. It's about thirty ft thick and it
starts at about the ninety meter mark and do you
have to you have to go down past it, and
I guess creepy. It is creepy, but it's also apparently
(17:43):
like even though you have a rebreather on or scuba apparatus.
It still steeps in through your skin while you're swimming
through it, and people will like throw up and UM
get itchy, kind of breakout and hives start to get
nauseated and headaches because it starts it creeps in through
your skin in just that short time. UM. So it's
really gross. It's really really toxic in this concentrated form.
(18:07):
It's like basically UM concentrated gas forms suspended in a
blanket layer and UM oxygen can't get past it. So
there it's an anaerobic environment in that lower layer UM,
which means it should be totally dead and lifeless. But
one of the things that they're finding out about blue
holes is that even in this anaerobic, toxic layer UM,
(18:31):
there is archaea, another type of life that's not quite
bacteria UM and definitely not you carryotes um or Procariot's.
I can never remember which one we are UM. But
they lived down there, their extreme aphiles is what they're
usually called these these days, And there's a whole kind
of teeming colony of life down there that actually takes
(18:55):
all of this stuff that accidentally falls into the blue
holes and digests them and turns them into this bioavailable
nutriatment ranch sediment that's just kind of trapped down at
the bottom of the Blue Hole. Yeah, and in the
Great Blue Hole when they went down there, they saw
I think they described it as a I say conk
They were saying conch. I'm not sure which is correct,
(19:16):
but I've always said conk um, but like a conk
graveyard down there, basically where it's just littered with all
these poor little sea creatures that happened to fall below
that that layer and they can't get back out, and
it's like Silence of the Lamb's esque. There's even like
scratch marks where you can tell they've tried to get
out over the years and we're unable to. Yeah, conk
(19:37):
fingernails that have peeled off and are stuck on the
sides of the walls. It's it's a bad jam. What
do you think about that Claires show? Is it going
to be any good? I like the concept, Yeah, I
mean too, but of a direct sequel, But I don't know.
I saw that they um, they seem to be recreating
the Lamb thing, and I think one of the I
(19:59):
just saw this movie like a week ago and it's
still just so good. Um. I think one of the
strengths of is that they don't show any of that story.
It's all just Clarice and her her telling of the
story makes it so much creep here. Yeah, there's no
like flashback scene or anything. Right, So this TV show
did that, and I'm wondering if that says a lot
(20:21):
about it or not. I'm wondering who is playing Buffalo Bill,
because they recreate some of that stuff. It looks like
my friend, it's our old pal, Tommy Chong, the note holder.
He got himself a pretty sweet gig he's playing him. No,
I'm just it's like, man, I mean they should just
get that that guy. He's around and still creepy looking. Yeah. Yeah,
(20:44):
Jamee Gum, the guy who played Jamee Gum. Yeah, sure,
uh yeah, why not? Uh so where are we here?
We were talking about little crabs and things trying to
get up unsuccessfully, which really is super sad. Yeah. So
there's a whole con Conch graveyard done. Who is saying
conch where they British? M hmmm, I don't remember because
(21:07):
I've always heard conk too. So yeah, there's a whole
conk and hermit crab graveyard down at the bottom of
the blue hole UM. And it is sad, but it's
just kind of like the circle of life thing. But again,
the weird thing about these blue holes is that some
of them are not circles. It's all just a one
way deposit of stuff from the top down to the bottom,
and everything just kind of gets stuck there and again
(21:29):
forms this pretty cool record isolated in time. UM. That's
not entirely true of all blue holes. It is for
the Great Blue Hole UM, and plenty of other blue
holes where it's just like things go in they don't
come back out. But there are other blue holes out there, UM,
including one called Green Banana Blue Hole UM in the
(21:49):
Gulf of Mexico I think off the coast of Sarasota.
That is UM pretty deep. It's like, uh, four hundred
and fifty feet I think for her in thirty five
ft below the surfaces the bottom of it UM and
it starts a hundred and fifty four ft below the surface,
and it's some incredibly vibrant, alive oasis in the midst
(22:12):
of this relatively barren Gulf of Mexico desert. UH. And
they are trying to figure out what the heck is
going on because other blue holes ares just like life suckers,
and this blue hole is like, have some more life.
You get some life, You get some life, and you
get some life. You know. It's a pretty interesting conundrum.
(22:34):
Does the green banana have that layer? Yes, although so
I'm sorry it doesn't have the layer, but it has
plenty of hydrogen sulfide in it. There's some, there's some, yeah,
And they're trying to figure out why. Because there's another
hole it's similar called Amberjack Hole that they've explored, and
it definitely has a layer, but there's also some sort
(22:54):
of nutrient flux or exchange with Amberjack too, But in
the green Banana, there's like it's like a two way
highway going from the top to the bottom up to
the rim. And what's interesting is they've figured out that
there are microbes there, I think archaa that actually eat
the inorganic carbon that leaches out of the dissolving walls
(23:15):
of the cave underwater. It eats it and turns it
into organic carbon, which then makes its way up somehow
to the rim, so that there's actually more life that
can be sustained there's more bioavailable carbon than would be
there if those microbes weren't chomping on it and turning
it into two organic carbon. So it's pretty interesting stuff.
(23:37):
And like, you don't find this kind of thing just anywhere.
So they're starting to really figure out that, like, these
blue holes are very unusual, unique communities, even among compared
to one another, but especially when you step back and
compared to like Topeka, it really knocks your socks off. Yeah,
(23:57):
and these are you know, they're all underwater capses ms.
There are parts of these cape systems that are still
unexplored because they're so vast or so deep. Uh, And
like you said, there's new in there. You know, it's
dangerous to to get down there, even if you're Richard
Branson in a fancy, you know, multimillion dollar submarine. One
of the things in the ones off the coast of
(24:18):
Florida that they're trying to figure out is whether they
actually connect to the aquifers in Florida and whether or
not that is the reason why, uh, there's some saltwater
intrusion going on in the state's drinking water. Yeah, and
it's it's possible that that flow of nutrients up and
down the green banana has to do with some sort
of tidal connection because there's like a flushing mechanism. Maybe
(24:41):
it could be from the aquifers. They don't know. Um,
but that would be a big one to figure out
because saltwater intrusion, especially down to Miami, is an enormous
problem and will probably lead to that city being abandoned
in the next fifty years. Poor Miami. Unless I mean,
we could always figure out desalination p sesses. But um, yeah,
(25:02):
that'd be a town to save, if you ask me.
I love Miami. Oh yeah. Oh it's vibrant. I'm not
the biggest fan, but you know it's not for everyone. Sure, no,
but it is. I like it. I think it's a
great town. Uh. Should we take another break here? Yes,
(25:22):
all right, we'll take a break and we'll finish up
with with diving in these things. I guess. Sure, it's okay, Chuck,
(25:50):
Like I said, you know, Jacques Cousteau kind of said, hey,
everybody go check out the Great Blue Hole. It's amazing,
But there are plenty of other blue holes out there
that everybody wants to dive on, and we should say
the Great Blue hole is not just famous because of
Jacques Cousto. It's not just noteworthy because of Jacques Cousto.
Not like he could have gone to just any blue
hole and it would have been like the the best
(26:12):
known blue hole in the world. Like it's incredibly large,
it's it's not the deepest blue hole on the planet.
I think that one actually goes to one in the
South China Sea called the Young Lee Marine Cavern, which
is about three nearly a thousand feet deep UM. This
one is uh, I think four hundred and fifteen feet
(26:33):
deep UM. But it's a thousand feet across. So if
you combine it's width and its depth, it's the biggest
blue hole out there as far as we've discovered yet. Yeah,
and that's what makes it great, and that's what makes
it a diving destination. But it is very dangerous. UM
is not something any kind of novice diver um wants
(26:53):
to take part in. In fact, I'm sure I'm not
sure how they You're probably not even allowed to unless
you're at a certain level of diving ability, would be
my guess. I think it how they can police that, right, Yeah,
that's that's my question too. I don't I don't know
how they police at all. I've I've read about one
called Jacob's Well, I think in New Mexico or Texas that, um,
(27:15):
some people die diving on it, and somebody tried to
put up a great that kept people out of the
rest of the cavern system and they just immediately removed
it and kept going. So I don't know how you
would police that either. But it is dangerous because it's
super super deep. It's dangerous because of that layer of
hydrogen sulfide that we talked about. UM, you know we've uh,
(27:39):
I know we talked about the Ben's in quite a
few episodes, but um, nitrogen narcosis can happen at just
a hundred feet down. So, like, the conditions are just
so different than anything you would normally encounter as a diver.
You can't just use your regular rule book and playbook
and think everything is going to be just fine. Like,
it's very specific conditions. Really got to know what you're
(28:00):
doing as far as blue hole specific diving goes. Uh.
And like we mentioned earlier, those three people died, um
at least three people. UM, there's probably been more, I
would guess, but three verified people have died in the
Great blue Hole alone. Yeah, from what I saw, when
you dive a blue hole, it's a combination of technical diving,
(28:23):
which is like really really deep diving that requires all
sorts of planning and skill, combined with cave diving, which requires,
like we we talked about before, all sorts of finesse.
Like if your flipper just flicks one of these spilea
them's um, it just dissolves into a cloud of silt
and you don't have any idea what's up and what's
(28:44):
down any longer. So it is really really tricky. Um,
and you know people do die. Uh. You saw that
one article I think I sent from fizz dot org
I think where I was talking about them, um searching
the cave system under Dean blue Hole in the Bahamas,
and um, they came across a diver who was still
(29:05):
wearing his nineteen seventies scuba equipment and had been left
in place there after dying there. So it's like really
really dangerous diving. And there's a blue hole in Egypt
that's considered the graveyard, the diver's graveyard, I think, so
that that diver looked like Brad Pitt in Once upon
a Time in Hollywood basically. I mean, wouldn't that make
(29:27):
it exponentially creepier to just the fact that it's like
seventies diving equipment, that's just something about it would make
that horrifying to come upon in a dark cave. It's
cooler looking equipment, for sure. They should have never progressed
past that design into the you know, mountain dew electric
(29:49):
yellow kind of thing that they've got going on today.
Back when they were called skin divers exactly. I don't
even know what that means. I don't either. Um, I
don't either, because you usually are wearing a wet suit.
Maybe maybe there there it's like the opposite of dry
suit diving. I don't know, who knows. Everybody in the
(30:10):
seventies was stoned on pot so you can't make heads
or tails at what they're talking about these things. Blue
holes are also a good place to go if you
are a free diver, uh and if you're interested in
setting any kind of a free diving record, a blue
hole is a great place to go, even though it's
dangerous because it's super deep. Um. We talked about free
(30:31):
diving before, but that's you know, that's diving without the
scuba gear. It's people that can hold their breath really
really long time, people that can um whose bodies can
adjust to those depths uh better I guess, or maybe
they're just trained to adjust better than other people. And
I think um it was the site up until semi
(30:52):
recently where they actually had a competition. They are called
Vertical Blue where they have set world records, but don't
think they do it there anymore, right, I don't know
if they hold Vertical Blue or not. But there is
a type of free diving called um no Limits free diving,
which is I think they stopped recording records because they
(31:13):
didn't want to encourage people to do this any longer.
It's like the most extreme version of one of the
most extreme sports there is. Free diving on its own,
it's just crazy nuts. But um no limits free diving
is where you have I think flippers on in a
wet suit in a mask, and that's it. You just
take a deep, deep breath and hold it, and then
you take a weighted sled that pulls you, plunges you
(31:36):
down to the depths of the blue hole very very quickly,
and then when you reach the level that you're trying
to reach usually just set a new record. Um, you
grab onto a buoy that's down there and it takes
you back up really quickly, and I was like, how
can you not get the bends? And the key is
the trick is you're not breathing at depth. You're just
(31:57):
holding your breath when you breathe it. That's how nitrogen
bubbles can get dissolved into your bloodstream, if you're just
holding your breath. I guess that that could happen, but
I think it's much less likely for it to happen
either way. It's not it can't possibly be good for
your body because these guys are holding like they're holding
their breath for nine minutes I saw in one case.
(32:19):
I can't imagine what it does to your body going
that fast down and then that fast back up again,
Like I can't go eight feet down in a swimming
pool without my ears doing something funny. You just come
up like, oh, it didn't hurt. But it's I don't know.
I mean, obviously it's practice and training and all that stuff,
but I say, no, thank you. Yeah, And so we
(32:40):
should tell people like with the depths, we're talking about
the guy who holds the record right now is named
Herbert Niche. He doved seven hundred and two feet like
this back in two thousand and seven, and in two
thousand and twelve he did it again, this time to
eight hundred and thirty one ft by but by that
time they weren't recording records any longer, so it's an
(33:01):
unofficial record. But eight hundred and thirty one feet on
a breath and then back up this nuts man. So
when you can imagine that when people try this stuff,
they die sometimes. And at that vertical blue competition at
Dean's Blue Hole, which is a Ankiellen pole or pool
up in the Bahamas, Um, it's a guy named Nicholas
(33:24):
Mvoli died back in two thousand and twelve. Very sad
it is. It's a very dangerous thing to do free diving.
It's also a dangerous thing to do diving on blue holes.
But I guess it's one of those ones where that
you work toward a goal and you finally get to
do it and your life has changed forever. Kind of
you know, you got anything else? I got nothing else?
(33:47):
I don't either. Man. If you want to know more
about blue holes, there is a lot to learn. Out there,
so just start researching and uh, thank us later. And
since I said thank us later, it's time for listener mail. Uh.
This is a good one. This was in response to
the in Double a CP episode. Hey guys, just finished
listening to in Double a CP made me think of
(34:08):
my father's college days. He attend an old miss when
James Meredith joined the school. Uh, and one day saw
an opportunity to help a young field reporter named Dan
Rather move his equipment from the registration building to the library.
My dad kept in contact with Mr Rather and let
him know that he was actually living in the same
dorm as Mr Meredith. Uh. And that is how his
time as a stringer began um, providing mostly audio clips
(34:32):
of events happening at the school. He said. At the
time he was selling reels to CBS, ABC, UH, CBC
and the BBC, making around six to eight hundred dollars
a week, which is real money for a college kid
in the sixties. I mean, that's real money now. It
was only a matter of time before the university found
out who was providing the footage and offered my dad
the choice of stopping or being expelled. He opted for expulsion,
(34:55):
thinking he could just enroll in another college, but then
learned that his and scripts were flagged and he could
not just pick up and move to another school, so
he had to go I know right, Uh, So he
had to go back to Old Miss and promised not
to report anymore so he could finish and get his degree,
which he did. Uh. Several years later, he married my
mom and they took a trip to the CBS studios
(35:18):
near them, and my dad suggested they pop in to
say hi to Dan Rather. My mom thought he was
pulling her leg. They went to the studio as to
speak to him and was promptly asked if they had
an appointment and was turned away. As they were leaving,
Dan Rather walk by and said John last name redacted,
How the heck are you curse word redacted? Uh? And
(35:39):
according to my mom, she almost fainted. Anyway, my family
has always taken a lot of pride that my dad
helped shed light on the UH integration at Old Miss. Granted,
his role could have been filled by almost any of
the students living in his dorm, but he was the
one who did it. And that is Brenda in sarah Sota, Florida.
That's a great story. Brendan, they jibes quite well with
(36:00):
our blue holes theme because there's some office hea soda too. Totally.
That's great. Yeah, the University of Mississippi's like, you better
stop reporting now get back to class and journalism school exactly.
Uh well, thanks again, Brenda, And if you want to
get in touch with this, like Brenda did, you can
send us an email to Stuff Podcast at iHeart radio
(36:21):
dot com. Stuff you Should Know is a production of
I Heart Radio for more podcasts for my heart Radio
because at the iHeart Radio app, Apple Podcasts, or wherever
you listen to your favorite shows.
Welcome to Stuff you Should Know, a production of I
Heart Radio. Hey you' welcome to the podcast. I'm Josh Clark,
and there's Charles W Chuck Bryan over there. Jerry's hovering
about and this is Stuff you should Know, another jazzy
(00:21):
Earth Science edition. Chuck. Yeah, and this is like, I
know we covered this head of an Internet Roundup? Did we?
I don't think we covered. I mean, we've done a
lot of cave stuff. We did sinkholes, cave dwellers, caving,
cave diving, peleology, and cave diving. So which one like
(00:43):
it could have come up in cave diving? I think maybe?
But I feel like I remember showing a picture. I'm
feeling Internet Roundup. Okay, yeah, we've been. That's kind of
funny because this, then is the second thing we've done
that we already did on Internet Roundup and then forgot about.
That's right, that's a trend. We're trending. Um. But the
cool thing about this one, Chuck, is that, like these
(01:05):
things that we're going to talk about today, blue holes
are so um new scientifically speaking, they're so unexplored um
that there's a lot we can get wrong, and no
one will know for like ten or fifteen years. Perfect.
We'll be done by then, isn't that great? Yeah, yeah,
we'll be We'll be sipping my ties on the beach
earning by then. Off German bearer bonds. What is that
(01:29):
trading places? No, that's a die Hard Okay, I think
that was a mash up. Oh yeah, that's funny how
things just kind of invade your subconscious like that. Well,
I mean trading places. They definitely were sipping drinks on
the beach, which did not happen in die Hard. No,
but he says it's like something like that. Yeah. Yeah,
(01:51):
he says, by the time the FBI figures out what's
going on, will be sitting on the beach. I think
he says sipping my ties earning. Does he say like
in trading places? That's right? Yeah, but he like breaks
the fourth wall and stairs right at the camera. We
need deliver. That would be great. So um, obviously, as
everyone's picked up by now, we're talking about blue holes
(02:13):
and if you don't know what a blue hole is,
I feel like this is definitely one of those ones
where we need to define it rather than just start
talking about it out of the gate. Uh, define what
it looks like or or the reveal of what it is. Okay, yeah,
we'll define what it looks like first. How about that?
All right, Well, it looks like a blue hole in
(02:34):
the ocean, like, you know, there's ocean, and then all
of a sudden, it's like, wait a minute, there's a
you know, sometimes they're pretty circular, like almost exactly circular,
and sometimes they're oddly shaped, but it's definitely like a
different color. And what it looks like from a bird's
eye view is like, well, hey, that looks like it
might be deeper right there, and it is. Yeah, and
(02:58):
it's a much much darker shade of blue than the
surrounding areas because it's a deep, deep hole in the
sea floor and the stuff around it is usually far
shallower comparatively speaking, so usually the area around is like
a much nicer, kind of lighter blue green, clearish color.
And then this is like this really stark, dark blue
(03:19):
hole again in the middle of the sea floor, and um,
it's a they're really popular diving spots. You have to
be a really good diver, as we'll see, to dive
on a blue hole, and they're also have long for centuries. Um,
been known locally um as really great fishing spots, both
commercially and for sport fishing. But the thing is, it's
(03:41):
like it's starting to become clear to geologists and biologists
that these things are kind of dotted all over the world.
There's some out to see, there's some that are actually landlocked, um,
but that they share some commonalities, and that these things,
these blue holes, submerged holes in the ground or the
sea floor are some of the weirdest, um most amazing
(04:04):
environments that that are exist on Earth right now. Yeah,
and you know, we should probably say that fishermen everywhere
are probably still mad at Jacques Cousteau who in nineteen
seventy two put the Great Blue Hole, which is one
particularly striking blue hole off the coast of Belize. He
put that on the map in nineteen seventy two on
(04:27):
a show that I used to love to watch, The
Undersea World of Jacques Gusta. Did you watch that? No,
I saw The Life Aquatic with Steve Zoo though so
close enough. Yeah, I was. I'm not sure what channel
it came on, or that was in reruns or if
I was watching it live, but it was sort of
like you know that in Mutual Omaha's Wild Kingdom were
(04:48):
the two big nature shows for me growing up as
far as turning me onto to all this stuff, right
the uh. I think the show ran from nineteen sixty
six to seventy six, so it's entirely possible you were
watching it live was a youngster. Probably reruns, yeah, but still,
I mean, I'm sure it immediately went in to reruns.
It was wildly popular. And that particular episode, if you're interested,
(05:09):
was Secrets of the Sunken Caves. But yeah, he put
this thing on the map, like, not literally, it was
on maps already, but he introduced it to the rest
of the world. UM. And the Great Blue Hole, as
that one in Belize that he covered is called UM
is on basically every serious scuba diver's bucket list to dive.
It's just it's just one of those places you have
(05:32):
to dive before you die. Hopefully you don't die while
you're diving on it, but it does happen sometimes it does. Uh.
And blue holes are basically uh. You know, I mentioned
sink or episode on sinkholes at the beginning. That was
a bit of an easter egg, because that's really all
they are is underwater sinkholes. It's a feature of what's
known as a karst system k a r st um
(05:56):
where you have this porous limestone making up the bedrock,
which you know leads to a lot of things. It's porous,
so it uh sentiment it like it wears away and
the road's kind of easier, I think than other kinds
of bedrock. That's where if you listen to any of
the caving episodes, is where you're gonna get some some
of these great stalactites and stalagmites because that acid rain
(06:19):
drips down and wears away that limestone, and you know,
it forms little icicles from the top and then when
it hits the bottom it forms reverse icicles on the floor.
And some of these blue holes have these stalactites and
stalagmites because they used to be you know, they used
to be land, right, they used to be dry caves.
(06:39):
Like that's the thing. Once they found stalactites and slag
mites um in these blue holes kind of give up
to see they're like, okay, this had to have been
above dry land because the dripping effect of water coming
from the top and then dripping down to the bottom.
It's kind of lost in the translation. When the thing
is already submerged in water, it has to be dry,
(07:00):
you know what I'm saying. Else not really No, I
think it just kind of goes every which way rather
than straight down. So yeah, when they when they started
finding these um collectively stalactites which come down from the
ceiling and stalagmites which come up from the floor. They're
collectively called spelio theems which we've talked about in plenty
of other episodes, when they started finding speleothems in in
(07:22):
these um blue holes, they're like, these were once on
dry land, which is pretty cool. But it also makes
sense too that these are just caves that formed at
some point in the great, great distant past on on
unearthed UM. I mean, where else are they going to form?
You know? Um? And it also makes sense that as
a cavern formed through the same process that forms spelio
(07:45):
theems um. It's just the water kind of carves out
a hole in the limestone, it dissolves it, and then
it gets bigger and bigger over time, and then all
of a sudden you have a cavern that the roof
of that area is not supported like it is surrounding
and so it's a vent going to clap in, whether
it's on dry land and as a sinkhole, or if
it's on dry land, and then that eventually becomes submerged
(08:06):
by water, you have a blue hole. So it's just
a sinkhole that's now out to see because the sea
level rise. Basically, Yeah, and one of the cool things
about the Great Blue Hole is when they started looking
at these stalactites and stalagmites, are like, well, some of
these look like you would expect because when things dripped,
they dripped straight down or build straight up. But some
(08:27):
of these are angled, sometimes up to twelve degrees, and
they're like, that's pretty interesting. So what it probably means
is that this thing formed over many, many many years
and the Earth's tectonic plates started shifting and so they
started dripping at different angles. So you've got this really
cool effect that happens where you have these you know, Uh,
(08:49):
it's something that you wouldn't see normally in a cave. Basically,
So if a couple of years ago, uh nat g
O and Richard Branson did an expedition where they were
are basically tried to map the Great Blue Hole three
D map. It and they went down there, and they
they went deeper than I think had been before in
a in a submarine like that, and found a bunch
(09:12):
of stuff. Um. They found that it was filling up
very slowly. I think they likened it to like an
underwater hour glass. Um, it's very slowly, so it's not
like it's going to be full anytime soon. Uh. They
found a two leader bottle of coke, uh, go pro
camera and some some dead people, some dead humans, a
(09:33):
lot of dead animals, but some dead humans as well. Yeah.
So the blue hole um has claimed at least three
lives that we know of on record right, um, which
is actually kind of a low ratio compared to some
other blue holes out there. UM. But they are still
down there, and like you said, two of them were
found by Branson and the nat GEO crew and they
(09:54):
came back and told the authorities and Belize exactly where
they were. Um. And they also apparently said, but look,
it's really quiet down there. It's really like a RESTful place,
like you could do a lot worse for a final
resting place than the bottom of the blue hole in Belize.
And I guess the authorities, I don't know if they
consulted with the families or what. But I was made
(10:15):
to think by some of the stuff I read that
the authorities in Belize said, you know, let's just leave
them down there and that will be their final resting place,
which sounds a little morbid from the outside, but that's
actually kind of customary when it comes to cave diving
in particular. I think we talked about that a little
bit in Caved the cave Diving episode, Yeah, for sure. Um.
(10:37):
And the cool thing about the Great Blue Hole is
that at one point it was it was in the jungle. Yeah,
so that would make it a different kind of blue hole,
which is still technically a blue hole, but it's called
the uh Ankielin I'm pretty sure that's right pool, which
is a blue hole, but it's landlocked, so like the
(10:57):
rim is exposed to dry air. It's not underwater like
on the sea floor because the sea levels just aren't
that high. And one of the interesting things about the
Great Blue Hole in Belize is it was at some
point because sea levels lowered so so dramatically um during
the last interglacial maximum about twenty six thousand years ago,
(11:19):
that that a significant portion of this vertical cave which
is now the Great Blue Hole in Belize was dry.
It was just totally dry, Like you could walk around
the top of the rim because it was no longer underwater.
You could jump in. You would die, but you could
jump in, and you would go all the way down
and then maybe at about the bottom, say twenty meters
(11:41):
of the cave, you would finally hit seawater. So over time,
the seawater levels have risen from the last time the
Earth was in a ice age UM, and the seawaters,
the sea levels have risen so much that now the
cave is totally submerged and is actually um many meters
under the surface of the sea because of sea level rise. Yeah,
(12:06):
and there's there's some really cool things you can learn from, uh,
from studying these blue holes, and maybe we should take
a break and learn about those right after this. Alright,
(12:36):
So there's a couple of really cool things that you
can learn by studying blue holes. UM. One of them is, uh,
you can look at this sediment and you can basically
kind of get a snapshot of of ancient weather patterns. UM.
I think when they when Branson and the gang went
down to the Great Blue Hole, they found a lot
(12:58):
of sediment where it's sort of indicated that UM in
different areas that indicated that that perhaps the Mayan Empire
had several severe hurricanes and maybe had something to do
with them not being around for much longer. Yeah, because
so the these UM these blue holes are basically at
a certain level cut off from the ocean above them,
(13:22):
like there's a point where there's no currents any longer,
whether the waves can affect it um, where there's no
oxygen dissolving past a certain boundary that we'll talk about
in a second, and so beneath a certain depth, they're
just like this, this perfect record of the Earth's geological history,
(13:44):
frozen and sequestered from everything else. So if you go
down there and this is the kind of the trend
that they're starting to figure out that these are the
expeditions are trying to launch and start taking samples of
the sediment, you can get like a really good picture
of Earth's say like her a cane passed or drought passed.
Apparently UM when when there's spikes and iron content, they
(14:05):
take that as UM from dust storms from Africa, which
which UM says that there's probably severe drought around the
world that year. So there's all of this information you
can glean that's just trapped and locked in the bottom
of these these great blue holes because they're so deep
and so remote and so unaffected by the world above them.
I just think that's amazing. It's super cool. Uh. The
(14:28):
other cool thing you can learn about is um sea
level rise over the years. We don't have the clearest
picture in science of anciency levels and when they were,
you know, like exact levels of when there were glacial
periods and interglacial periods and the rising and falling of
the seas. But if you go down there and you
radio carbon date these stalactites and stalagmites, you can compare
(14:51):
them to the relative depths of the whole cave system,
and then you can basically say when was their air here,
when was there water here, and get a pretty, you know,
at least a much better picture of what the sea
levels used to look like. Yeah, and they figured out
that the cave itself was formed um between about a
hundred and fifty three thousand years ago to about fifteen
(15:12):
thousand years ago. There are four major dry periods where
the cave was exposed during that time, and I don't
know if they figured out from the um the Great
Blue Hole itself or if they just already knew this,
But apparently in the past the sea level has risen
really quickly a couple of different times UM. I think
(15:33):
eleven thousand years ago and eight thousand years ago. Over
the course of less than a hundred and fifty years,
it rose twenty five ft and then again twenty one
ft in less than less than two centuries, which is
a really significant rise UM. And having information like that
is really vital to kind of placing our current sea
(15:54):
level rise and experience of climate change in context in
this greater context of Earth's history and possibly it's normal
rhythms or what's abnormal. So to be able to understand
that because of the kind of the record that's kept
in the blue holes is extremely helpful. Yeah. And I
think the usual level of sea rises about a meter
(16:16):
every century, so a spike of twenty four and twenty
ft is really really big. It's I mean, you could
basically watch it happening. You know, it's start to come
up around your ankles if you stood in there the
same place long enough. Another cool thing about blue holes,
and in particularly the Great blue hole is that there
(16:36):
is a layer of hydrogen sulfide that basically acts like
a blanket, uh, And there are different depths depending on
which blue hole you're talking about, But it's just a
real concentrated layer of hydrogen sulfide. That is, it's a
bike product of decaying plant material, and it's kind of stinky.
It's kind of that sulfury eggy smell that you might
(16:57):
smell sometimes, and it's uh, really really clear water below
in this area it is really brown and kind of gross,
and then you know it's it's so far down it
doesn't look brown and gross from the top. It still
looks nice and blue. But it's really a separation point
where above it you have life and below it there's
no oxygen getting through, so you have no life now.
(17:20):
And I saw it described as like kind of hazy brown,
kind of cobwebby layer. I think in the Great Blue
Hole in particular. It's about thirty ft thick and it
starts at about the ninety meter mark and do you
have to you have to go down past it, and
I guess creepy. It is creepy, but it's also apparently
(17:43):
like even though you have a rebreather on or scuba apparatus.
It still steeps in through your skin while you're swimming
through it, and people will like throw up and UM
get itchy, kind of breakout and hives start to get
nauseated and headaches because it starts it creeps in through
your skin in just that short time. UM. So it's
really gross. It's really really toxic in this concentrated form.
(18:07):
It's like basically UM concentrated gas forms suspended in a
blanket layer and UM oxygen can't get past it. So
there it's an anaerobic environment in that lower layer UM,
which means it should be totally dead and lifeless. But
one of the things that they're finding out about blue
holes is that even in this anaerobic, toxic layer UM,
(18:31):
there is archaea, another type of life that's not quite
bacteria UM and definitely not you carryotes um or Procariot's.
I can never remember which one we are UM. But
they lived down there, their extreme aphiles is what they're
usually called these these days, And there's a whole kind
of teeming colony of life down there that actually takes
(18:55):
all of this stuff that accidentally falls into the blue
holes and digests them and turns them into this bioavailable
nutriatment ranch sediment that's just kind of trapped down at
the bottom of the Blue Hole. Yeah, and in the
Great Blue Hole when they went down there, they saw
I think they described it as a I say conk
They were saying conch. I'm not sure which is correct,
(19:16):
but I've always said conk um, but like a conk
graveyard down there, basically where it's just littered with all
these poor little sea creatures that happened to fall below
that that layer and they can't get back out, and
it's like Silence of the Lamb's esque. There's even like
scratch marks where you can tell they've tried to get
out over the years and we're unable to. Yeah, conk
(19:37):
fingernails that have peeled off and are stuck on the
sides of the walls. It's it's a bad jam. What
do you think about that Claires show? Is it going
to be any good? I like the concept, Yeah, I
mean too, but of a direct sequel, But I don't know.
I saw that they um, they seem to be recreating
the Lamb thing, and I think one of the I
(19:59):
just saw this movie like a week ago and it's
still just so good. Um. I think one of the
strengths of is that they don't show any of that story.
It's all just Clarice and her her telling of the
story makes it so much creep here. Yeah, there's no
like flashback scene or anything. Right, So this TV show
did that, and I'm wondering if that says a lot
(20:21):
about it or not. I'm wondering who is playing Buffalo Bill,
because they recreate some of that stuff. It looks like
my friend, it's our old pal, Tommy Chong, the note holder.
He got himself a pretty sweet gig he's playing him. No,
I'm just it's like, man, I mean they should just
get that that guy. He's around and still creepy looking. Yeah. Yeah,
(20:44):
Jamee Gum, the guy who played Jamee Gum. Yeah, sure,
uh yeah, why not? Uh so where are we here?
We were talking about little crabs and things trying to
get up unsuccessfully, which really is super sad. Yeah. So
there's a whole con Conch graveyard done. Who is saying
conch where they British? M hmmm, I don't remember because
(21:07):
I've always heard conk too. So yeah, there's a whole
conk and hermit crab graveyard down at the bottom of
the blue hole UM. And it is sad, but it's
just kind of like the circle of life thing. But again,
the weird thing about these blue holes is that some
of them are not circles. It's all just a one
way deposit of stuff from the top down to the bottom,
and everything just kind of gets stuck there and again
(21:29):
forms this pretty cool record isolated in time. UM. That's
not entirely true of all blue holes. It is for
the Great Blue Hole UM, and plenty of other blue
holes where it's just like things go in they don't
come back out. But there are other blue holes out there, UM,
including one called Green Banana Blue Hole UM in the
(21:49):
Gulf of Mexico I think off the coast of Sarasota.
That is UM pretty deep. It's like, uh, four hundred
and fifty feet I think for her in thirty five
ft below the surfaces the bottom of it UM and
it starts a hundred and fifty four ft below the surface,
and it's some incredibly vibrant, alive oasis in the midst
(22:12):
of this relatively barren Gulf of Mexico desert. UH. And
they are trying to figure out what the heck is
going on because other blue holes ares just like life suckers,
and this blue hole is like, have some more life.
You get some life, You get some life, and you
get some life. You know. It's a pretty interesting conundrum.
(22:34):
Does the green banana have that layer? Yes, although so
I'm sorry it doesn't have the layer, but it has
plenty of hydrogen sulfide in it. There's some, there's some, yeah,
And they're trying to figure out why. Because there's another
hole it's similar called Amberjack Hole that they've explored, and
it definitely has a layer, but there's also some sort
(22:54):
of nutrient flux or exchange with Amberjack too, But in
the green Banana, there's like it's like a two way
highway going from the top to the bottom up to
the rim. And what's interesting is they've figured out that
there are microbes there, I think archaa that actually eat
the inorganic carbon that leaches out of the dissolving walls
(23:15):
of the cave underwater. It eats it and turns it
into organic carbon, which then makes its way up somehow
to the rim, so that there's actually more life that
can be sustained there's more bioavailable carbon than would be
there if those microbes weren't chomping on it and turning
it into two organic carbon. So it's pretty interesting stuff.
(23:37):
And like, you don't find this kind of thing just anywhere.
So they're starting to really figure out that, like, these
blue holes are very unusual, unique communities, even among compared
to one another, but especially when you step back and
compared to like Topeka, it really knocks your socks off. Yeah,
(23:57):
and these are you know, they're all underwater capses ms.
There are parts of these cape systems that are still
unexplored because they're so vast or so deep. Uh, And
like you said, there's new in there. You know, it's
dangerous to to get down there, even if you're Richard
Branson in a fancy, you know, multimillion dollar submarine. One
of the things in the ones off the coast of
(24:18):
Florida that they're trying to figure out is whether they
actually connect to the aquifers in Florida and whether or
not that is the reason why, uh, there's some saltwater
intrusion going on in the state's drinking water. Yeah, and
it's it's possible that that flow of nutrients up and
down the green banana has to do with some sort
of tidal connection because there's like a flushing mechanism. Maybe
(24:41):
it could be from the aquifers. They don't know. Um,
but that would be a big one to figure out
because saltwater intrusion, especially down to Miami, is an enormous
problem and will probably lead to that city being abandoned
in the next fifty years. Poor Miami. Unless I mean,
we could always figure out desalination p sesses. But um, yeah,
(25:02):
that'd be a town to save, if you ask me.
I love Miami. Oh yeah. Oh it's vibrant. I'm not
the biggest fan, but you know it's not for everyone. Sure, no,
but it is. I like it. I think it's a
great town. Uh. Should we take another break here? Yes,
(25:22):
all right, we'll take a break and we'll finish up
with with diving in these things. I guess. Sure, it's okay, Chuck,
(25:50):
Like I said, you know, Jacques Cousteau kind of said, hey,
everybody go check out the Great Blue Hole. It's amazing,
But there are plenty of other blue holes out there
that everybody wants to dive on, and we should say
the Great Blue hole is not just famous because of
Jacques Cousto. It's not just noteworthy because of Jacques Cousto.
Not like he could have gone to just any blue
hole and it would have been like the the best
(26:12):
known blue hole in the world. Like it's incredibly large,
it's it's not the deepest blue hole on the planet.
I think that one actually goes to one in the
South China Sea called the Young Lee Marine Cavern, which
is about three nearly a thousand feet deep UM. This
one is uh, I think four hundred and fifteen feet
(26:33):
deep UM. But it's a thousand feet across. So if
you combine it's width and its depth, it's the biggest
blue hole out there as far as we've discovered yet. Yeah,
and that's what makes it great, and that's what makes
it a diving destination. But it is very dangerous. UM
is not something any kind of novice diver um wants
(26:53):
to take part in. In fact, I'm sure I'm not
sure how they You're probably not even allowed to unless
you're at a certain level of diving ability, would be
my guess. I think it how they can police that, right, Yeah,
that's that's my question too. I don't I don't know
how they police at all. I've I've read about one
called Jacob's Well, I think in New Mexico or Texas that, um,
(27:15):
some people die diving on it, and somebody tried to
put up a great that kept people out of the
rest of the cavern system and they just immediately removed
it and kept going. So I don't know how you
would police that either. But it is dangerous because it's
super super deep. It's dangerous because of that layer of
hydrogen sulfide that we talked about. UM, you know we've uh,
(27:39):
I know we talked about the Ben's in quite a
few episodes, but um, nitrogen narcosis can happen at just
a hundred feet down. So, like, the conditions are just
so different than anything you would normally encounter as a diver.
You can't just use your regular rule book and playbook
and think everything is going to be just fine. Like,
it's very specific conditions. Really got to know what you're
(28:00):
doing as far as blue hole specific diving goes. Uh.
And like we mentioned earlier, those three people died, um
at least three people. UM, there's probably been more, I
would guess, but three verified people have died in the
Great blue Hole alone. Yeah, from what I saw, when
you dive a blue hole, it's a combination of technical diving,
(28:23):
which is like really really deep diving that requires all
sorts of planning and skill, combined with cave diving, which requires,
like we we talked about before, all sorts of finesse.
Like if your flipper just flicks one of these spilea
them's um, it just dissolves into a cloud of silt
and you don't have any idea what's up and what's
(28:44):
down any longer. So it is really really tricky. Um,
and you know people do die. Uh. You saw that
one article I think I sent from fizz dot org
I think where I was talking about them, um searching
the cave system under Dean blue Hole in the Bahamas,
and um, they came across a diver who was still
(29:05):
wearing his nineteen seventies scuba equipment and had been left
in place there after dying there. So it's like really
really dangerous diving. And there's a blue hole in Egypt
that's considered the graveyard, the diver's graveyard, I think, so
that that diver looked like Brad Pitt in Once upon
a Time in Hollywood basically. I mean, wouldn't that make
(29:27):
it exponentially creepier to just the fact that it's like
seventies diving equipment, that's just something about it would make
that horrifying to come upon in a dark cave. It's
cooler looking equipment, for sure. They should have never progressed
past that design into the you know, mountain dew electric
(29:49):
yellow kind of thing that they've got going on today.
Back when they were called skin divers exactly. I don't
even know what that means. I don't either. Um, I
don't either, because you usually are wearing a wet suit.
Maybe maybe there there it's like the opposite of dry
suit diving. I don't know, who knows. Everybody in the
(30:10):
seventies was stoned on pot so you can't make heads
or tails at what they're talking about these things. Blue
holes are also a good place to go if you
are a free diver, uh and if you're interested in
setting any kind of a free diving record, a blue
hole is a great place to go, even though it's
dangerous because it's super deep. Um. We talked about free
(30:31):
diving before, but that's you know, that's diving without the
scuba gear. It's people that can hold their breath really
really long time, people that can um whose bodies can
adjust to those depths uh better I guess, or maybe
they're just trained to adjust better than other people. And
I think um it was the site up until semi
(30:52):
recently where they actually had a competition. They are called
Vertical Blue where they have set world records, but don't
think they do it there anymore, right, I don't know
if they hold Vertical Blue or not. But there is
a type of free diving called um no Limits free diving,
which is I think they stopped recording records because they
(31:13):
didn't want to encourage people to do this any longer.
It's like the most extreme version of one of the
most extreme sports there is. Free diving on its own,
it's just crazy nuts. But um no limits free diving
is where you have I think flippers on in a
wet suit in a mask, and that's it. You just
take a deep, deep breath and hold it, and then
you take a weighted sled that pulls you, plunges you
(31:36):
down to the depths of the blue hole very very quickly,
and then when you reach the level that you're trying
to reach usually just set a new record. Um, you
grab onto a buoy that's down there and it takes
you back up really quickly, and I was like, how
can you not get the bends? And the key is
the trick is you're not breathing at depth. You're just
(31:57):
holding your breath when you breathe it. That's how nitrogen
bubbles can get dissolved into your bloodstream, if you're just
holding your breath. I guess that that could happen, but
I think it's much less likely for it to happen
either way. It's not it can't possibly be good for
your body because these guys are holding like they're holding
their breath for nine minutes I saw in one case.
(32:19):
I can't imagine what it does to your body going
that fast down and then that fast back up again,
Like I can't go eight feet down in a swimming
pool without my ears doing something funny. You just come
up like, oh, it didn't hurt. But it's I don't know.
I mean, obviously it's practice and training and all that stuff,
but I say, no, thank you. Yeah, And so we
(32:40):
should tell people like with the depths, we're talking about
the guy who holds the record right now is named
Herbert Niche. He doved seven hundred and two feet like
this back in two thousand and seven, and in two
thousand and twelve he did it again, this time to
eight hundred and thirty one ft by but by that
time they weren't recording records any longer, so it's an
(33:01):
unofficial record. But eight hundred and thirty one feet on
a breath and then back up this nuts man. So
when you can imagine that when people try this stuff,
they die sometimes. And at that vertical blue competition at
Dean's Blue Hole, which is a Ankiellen pole or pool
up in the Bahamas, Um, it's a guy named Nicholas
(33:24):
Mvoli died back in two thousand and twelve. Very sad
it is. It's a very dangerous thing to do free diving.
It's also a dangerous thing to do diving on blue holes.
But I guess it's one of those ones where that
you work toward a goal and you finally get to
do it and your life has changed forever. Kind of
you know, you got anything else? I got nothing else?
(33:47):
I don't either. Man. If you want to know more
about blue holes, there is a lot to learn. Out there,
so just start researching and uh, thank us later. And
since I said thank us later, it's time for listener mail. Uh.
This is a good one. This was in response to
the in Double a CP episode. Hey guys, just finished
listening to in Double a CP made me think of
(34:08):
my father's college days. He attend an old miss when
James Meredith joined the school. Uh, and one day saw
an opportunity to help a young field reporter named Dan
Rather move his equipment from the registration building to the library.
My dad kept in contact with Mr Rather and let
him know that he was actually living in the same
dorm as Mr Meredith. Uh. And that is how his
time as a stringer began um, providing mostly audio clips
(34:32):
of events happening at the school. He said. At the
time he was selling reels to CBS, ABC, UH, CBC
and the BBC, making around six to eight hundred dollars
a week, which is real money for a college kid
in the sixties. I mean, that's real money now. It
was only a matter of time before the university found
out who was providing the footage and offered my dad
the choice of stopping or being expelled. He opted for expulsion,
(34:55):
thinking he could just enroll in another college, but then
learned that his and scripts were flagged and he could
not just pick up and move to another school, so
he had to go I know right, Uh, So he
had to go back to Old Miss and promised not
to report anymore so he could finish and get his degree,
which he did. Uh. Several years later, he married my
mom and they took a trip to the CBS studios
(35:18):
near them, and my dad suggested they pop in to
say hi to Dan Rather. My mom thought he was
pulling her leg. They went to the studio as to
speak to him and was promptly asked if they had
an appointment and was turned away. As they were leaving,
Dan Rather walk by and said John last name redacted,
How the heck are you curse word redacted? Uh? And
(35:39):
according to my mom, she almost fainted. Anyway, my family
has always taken a lot of pride that my dad
helped shed light on the UH integration at Old Miss. Granted,
his role could have been filled by almost any of
the students living in his dorm, but he was the
one who did it. And that is Brenda in sarah Sota, Florida.
That's a great story. Brendan, they jibes quite well with
(36:00):
our blue holes theme because there's some office hea soda too. Totally.
That's great. Yeah, the University of Mississippi's like, you better
stop reporting now get back to class and journalism school exactly.
Uh well, thanks again, Brenda, And if you want to
get in touch with this, like Brenda did, you can
send us an email to Stuff Podcast at iHeart radio
(36:21):
dot com. Stuff you Should Know is a production of
I Heart Radio for more podcasts for my heart Radio
because at the iHeart Radio app, Apple Podcasts, or wherever
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