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El Niño and La Niña – Australia's Boom-and-Bust Rainfall · Talking Science

0:00
You know, there is a very particular kind of
0:02
memory that a lot of Australians carry. For sure.
0:07
It doesn't even matter if you spent your whole
0:08
life working on the land or if you've, you know,
0:10
never left the city. It's that memory of a summer
0:13
defined by just relentless dust. Right. The really
0:16
bad ones. Exactly. Like dry dams, total fire
0:20
bans stretching on for weeks, the sky completely
0:24
hazy with smoke. And then maybe just a few years
0:27
later, you get the exact opposite. Total whiplash.
0:29
Yeah. Summer of absolute relentless rain, swollen
0:32
rivers, paddocks turned into shallow lakes and
0:35
like mold literally growing on your shoes in
0:37
the closet. It is. It's a landscape defined by
0:41
incredible extremes. And looking at those wild
0:43
swings going from bone dry to completely underwater.
0:46
it is incredibly tempting to just write it off
0:48
as, you know, random runs of bad luck. Or just
0:51
the chaotic nature of the weather acting out,
0:53
right? Exactly. But the reality is far more structured
0:55
than that. Right. And that's exactly why we're
0:57
here today. I've got a massive stack of sources
1:00
in front of me for this deep dive, research papers,
1:03
climate data, and particularly this incredibly
1:06
detailed, extensive article that breaks down
1:09
the actual mechanics behind Australia's extreme
1:11
climate swings. It's fascinating stuff. It really
1:14
is. And the mission... of our deep dive today
1:17
is to take all this source material and decode
1:19
this massive, slow moving ocean and atmosphere
1:23
pattern that dictates these wild extremes. And
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I think the wildest part of all this is that
1:28
the pattern governing whether an Australian farm
1:30
gets rain or dust is happening thousands of kilometers
1:34
offshore. Yeah, way out in the middle of the
1:35
tropical Pacific Ocean. Which is just crazy to
1:38
think about. We are talking about the El Nino
1:40
Southern Oscillation. Or scientists usually just
1:43
shorten that to ENSO. Right, ENSO. And it is,
1:46
without a doubt, the single biggest driver of
1:49
year to year climate variability affecting not
1:52
just Australia, but large parts of the globe.
1:54
So our goal today for you, the listener, is to
1:57
break down exactly what this is, the physical
1:59
machinery of how it pushes the weather between
2:01
such wild extremes, and honestly, the limits
2:04
of our ability to predict it. And we're going
2:07
to do it without relying on a textbook full of
2:10
jargon. OK, let's unpack this, because before
2:12
we can understand how the weather breaks down
2:14
into these crazy extremes, we have to understand
2:17
the baseline. Right. What's normal? Yeah. If
2:19
we are looking at the Pacific Ocean in a quote
2:22
unquote normal year, what are the baseline rules?
2:25
Well, the best place to start looking is right
2:28
along the equator. In an ordinary year, you have
2:32
prevailing winds called the trade winds. Okay.
2:34
And these blow steadily from east to west. So
2:37
picture a massive continuous current of air moving
2:40
from the coast of South America, tracking all
2:43
the way across the vast expanse of the Pacific
2:45
Ocean, heading straight toward Australia and
2:48
Indonesia. And because that wind is blowing across
2:50
thousands of miles of open ocean constantly,
2:53
it is actually doing physical work on the water,
2:56
right? Like it's creating friction. Exactly.
2:59
Friction. And that friction is dragging the sun
3:02
-warmed surface water of the ocean westward.
3:04
The wind literally pushes this thin layer of
3:08
warm water. And over thousands of miles, that
3:11
water piles up. It forms a remarkably deep layer
3:15
of warm water near Indonesia and northern Australia.
3:18
And there's a name for that, right? Yeah, oceanographers
3:20
call this the warm pool. The warm pool. Okay,
3:23
so the wind is shoveling all this warm surface
3:25
water to the west. But, I mean, there can't just
3:28
be an empty hole in the ocean back in the east
3:30
near South America. Something has to replace
3:32
the water that was pushed away. Nature abhors
3:35
a vacuum, right? Exactly. So as that warm surface
3:37
water departs toward Australia, colder water
3:40
is drawn up from the deep ocean off... the coast
3:42
of South America to take its place. Okay, that
3:44
makes sense. This process is called upwelling.
3:47
The Earth's rotation actually helps pull this
3:50
deep, frigid water to the surface. So the end
3:53
result is that in a typical year, the western
3:55
Pacific near Australia is noticeably warmer at
3:58
the surface than the eastern Pacific near Peru
4:00
and Ecuador. You've got it. Think about it like
4:02
having a giant bathtub. If you turn on a massive
4:05
industrial -sized fan on one side of the tub
4:08
blowing across the surface, that wind is going
4:11
to physically push all the warm water to bunch
4:14
up on the far side. That's a great way to picture
4:16
it. Right. So one side of your bathtub now has
4:19
a deep pile of warm water, and the side near
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the fan has colder water rising from the bottom
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to replace it. That bathtub is our baseline Pacific
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Ocean. And that seemingly simple temperature
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difference. I mean, sometimes it's just a few
4:34
degrees between the east and the west. It has
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enormous consequences. Because it affects the
4:38
air above it. Exactly. It acts like an engine
4:41
for the atmosphere. This difference in sea surface
4:44
temperature drives a massive loop of air, which
4:47
meteorologists call the Walker circulation. Which
4:49
operates on a pretty simple thermodynamic principle,
4:52
right? Hot air rises. It does. So over that deep,
4:55
warm pool near Australia and Indonesia, the ocean
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heavily heats the air directly above it. Okay.
5:01
That warm, moisture -laden air rises high into
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the atmosphere. As it gains altitude, it cools
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down. And cool air can't hold as much moisture.
5:09
Right. So it releases all that water as rainfall.
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This is the primary reason why northern Australia
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and Indonesia get such reliable heavy rain in
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a normal year. But that air doesn't just stay
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up there in the stratosphere. I mean, it has
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to go somewhere once it hits the ceiling of the
5:25
lower atmosphere. Yeah, it gets pushed eastward
5:27
at high altitude, traveling all the way back
5:29
across the Pacific. Towards South America. Exactly.
5:32
By the time it reaches the eastern Pacific near
5:35
South America, it has cooled significantly and
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it begins to sink back down over that colder,
5:40
upwelling water. And here is a fundamental rule
5:43
of how our weather works, which you see all over
5:45
the sources. Sinking air suppresses rainfall.
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Yes, it creates high pressure and clear skies.
5:51
So the eastern Pacific stays relatively dry.
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And then what? Finally, that air flows back westward
5:57
along the ocean surface as those trade winds
5:59
we started with. It's an elegant, self -reinforcing
6:03
loop. The wind pushes the water. The warm water
6:06
heats the air, the air rises and makes rain,
6:08
and then flows back east to sink and create more
6:11
wind. It's a perfectly balanced engine. But the
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focus of our sources today is what happens when
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that engine breaks down, the phenomenon known
6:18
as El Nino. Right. During an El Nino event, that
6:22
giant fan over the bathtub loses power. The winds
6:26
just stop. Well, the steady trade winds weaken,
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and in some rare cases, they can even briefly
6:31
reverse direction. Wow, reversed completely.
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Why does that happen? The reasons are incredibly
6:36
complex. It often involves temporary disruptions
6:40
in the atmosphere, like... Large waves of stormy
6:43
weather traveling eastward along the equator,
6:45
which interrupt the steady flow of the trade
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winds. So the wind just loses its grip on the
6:49
ocean, and without that steady westward push,
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gravity takes over, right? The tub levels out.
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Exactly. That massive warm pool of water that
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was banked up near Australia and Indonesia just
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sloshes back eastward across the Pacific. Migrating
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towards South America. Yeah. The term oceanographers
7:06
use is a Kelvin wave, but slosh is honestly a
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brilliant way to visualize it. A giant slosh.
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It is a slow motion migration of millions of
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square kilometers of warm ocean water. It takes
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months for this warm water to travel across the
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Pacific. Right. And here is the mechanism that
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actually changes the weather. The rising air
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and the massive rain clouds, they don't stay
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over Australia. They follow the warm water. Because
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the heat source moves. So the storm clouds move
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with it. Right. I really want to emphasize this
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point for everyone listening. The rain doesn't
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magically vanish from the earth. It literally
7:40
just relocates to the central or eastern Pacific.
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That's spot on. But for Australia, that relocation
7:47
is devastating. Because the rain is gone. Because
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the rising air moved away. Yeah. Yeah, the system
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flips. You end up with sinking air over the Australian
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continent. And as we established... Sinking air
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suppresses rainfall. Exactly. That means below
8:00
average rainfall, a sharply increased likelihood
8:03
of drought, and a severely elevated risk of bushfires
8:07
because the vegetation dries out and soil moisture
8:10
plummets. Though it shifts the odds, right. It
8:12
doesn't mean a catastrophic fire is guaranteed
8:15
in every single town because local geography
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and weather fronts still play a role. Right.
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It's not a guarantee. But it heavily loads the
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dice toward drier conditions across huge swaths
8:24
of the continent. Very much so. But here's something
8:27
I found really fascinating in the research. Scientists
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don't just look out the window and say, looks
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dry, must be El Niño. No, no, not at all. They
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have incredibly strict metrics for this. How
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do they actually measure the slosh? Well, they
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focus their instruments on a very specific patch
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of the central and eastern tropical Pacific.
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It's designated as the Niño 3 .4 region. Nino
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3 .4. Yeah. This specific box of ocean is monitored
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because it acts as the pivot point for the whole
8:57
atmospheric engine. Forecasters constantly compare
9:01
the current water temperature in that box against
9:04
the long -term historical average. So they're
9:06
basically waiting to see if that specific patch
9:09
hits a certain temperature threshold. A temperature
9:11
threshold sustained over time. For an agency
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like the Bureau of Meteorology to officially
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declare an El Nino. that Niño 3 .4 region has
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to remain warmer than average for several consecutive
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months. It can't just be a quick spike. Exactly.
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And furthermore, it must be coupled with the
9:27
atmosphere. The ocean and the sky have to agree.
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What does that mean? You need the warm water
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in that box, plus the observable weakening of
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the trade winds and the shift in rainfall patterns
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we talked about. And the sources note that this
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entire system can swing in the complete opposite
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direction too, which gives us La Niña. If El
9:45
Nino is the fan turning off, La Nina is the fan
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getting stuck on overdrive. That's a great way
9:50
to put it. During La Nina, those trade winds
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overperform. They blow with far more intensity
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than normal. Pushing even more water. Yeah. This
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drives an excessive amount of warm water into
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the western Pacific, building an unusually deep
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and intensely hot, warm pool right on Australia's
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doorstep. Which means the updraft of rising air
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goes into overdrive, too. The rising air and
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convective rainfall intensify dramatically over
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Australia and Indonesia. This brings massive
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amounts of moisture, leading to above average
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rainfall. Which sounds nice during a drought.
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It sounds like a relief, but it brings a severe
10:24
risk of catastrophic flooding. This is especially
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true if you get multiple consecutive La Nina
10:29
years. Because the ground is just full. Exactly.
10:32
The soil becomes so saturated that any new rain
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immediately turns into floodwater, much like
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the devastating multi -year floods eastern Australia
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saw in the early 2020s. I do want to push back
10:43
on something here, though, acting on behalf of
10:45
anyone who follows climate news. Okay, sure.
10:48
The sources state that neutral conditions, where
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the ocean is neither El Nino nor La Nina, are
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actually the most common state. They are. The
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Pacific spends more time in neutral than in either
10:58
extreme. But wait, if that's true, why does it
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feel like we are constantly hearing about El
11:04
Niño or La Niña in the news? Are we just obsessed
11:07
with the extremes? It is a totally valid observation.
11:10
But the reason the extremes dominate the conversation
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is entirely due to human impact. Because normal
11:15
doesn't make the news. Right. A neutral year
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means the weather is generally doing what we
11:19
expect. Farmers get their average rainfall. Fire
11:22
seasons stay within normal parameters. We don't
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write news headlines about the bathtub staying
11:27
perfectly full. We only care when it breaks.
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We make headlines when the bathtub overflows
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and destroys the house or when it runs completely
11:34
dry and the crops die. Yeah. The extremes dictate
11:38
our disasters. Right. So when that temperature
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needle in the Nino 3 .4 region starts to move.
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The entire world pays attention because food
11:47
security, the economy, and lives are on the line.
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Here's where it gets really interesting. We threw
11:52
these terms around El Nino and La Nina, and they
11:55
are used by serious meteorologists running supercomputers
11:58
today. But their origins have nothing to do with
12:00
modern science. Not at all. The origin story
12:03
is centuries old. It originates from a completely
12:05
different kind of observation. Generations ago,
12:08
long before weather satellites, Fishing communities
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along the coast of Peru and Ecuador noticed a
12:13
recurring pattern. Under normal conditions, their
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coastal waters were freezing cold, but incredibly
12:19
rich in nutrients, all thanks to that deep ocean
12:22
upwelling we discussed earlier. Because the cold
12:25
water pulls up nitrogen and phosphorus from the
12:27
ocean floor, right? Oh, wow. Which feeds the
12:29
phytoplankton, which feeds the fish. It is an
12:32
incredibly productive food web. Exactly. But
12:35
these fishermen noticed that every few years,
12:38
this cold water would vanish. The outpouring
12:41
would stop. The coastal waters would turn unusually
12:44
warm. And without those nutrients, the fish stocks
12:46
would completely collapse. Just a disaster for
12:49
them. Their livelihood would be devastated. And
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the timing of this warm water arriving usually
12:54
peaked around December. Around Christmastime.
12:56
Right. So out of a cultural connection to the
12:59
season, they named this periodic, devastating
13:02
warming of the ocean El Nino. which translates
13:05
to the boy child, referring directly to the Christ
13:08
child. It is staggering to think about the butterfly
13:10
effect of that. A term coined by Peruvian fishermen
13:14
to describe why they couldn't catch any fish
13:16
in December is now the strict scientific label
13:19
for a phenomenon that dictates whether an Australian
13:21
wheat farm survives the summer. It really shows
13:24
how connected everything is. Later in the 20th
13:26
century, scientists began connecting the dots
13:29
and added the second half of the acronym, the
13:31
Southern Oscillation. This is the SO in ESO.
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Yes. They discovered that the ocean temperature
13:37
changes were directly linked to a massive atmospheric
13:41
seesaw in pressure. They found that surface air
13:44
pressure at Darwin in northern Australia and
13:47
air pressure at Tahiti out in the Central Pacific
13:49
move in exact opposite directions. So if the
13:52
pressure goes up in Darwin, it goes down in Tahiti.
13:55
They are connected. Meteorologists track this
13:57
using the Southern Oscillation Index, or the
14:00
SOI. By comparing the pressure difference between
14:03
those two locations, they have a reliable mathematical
14:05
gauge of how the atmosphere is responding. So
14:08
it's another way to measure it. Yeah, it tells
14:10
us whether the whole system is leaning toward
14:11
El Nino, plunging into La Nina, or just sitting
14:14
in neutral. And the shockwaves of that atmospheric
14:17
seesaw travel far beyond the Pacific Rim because
14:20
the atmosphere is deeply interconnected, altering
14:23
the walker circulation messes with the jet streams
14:25
globally. The teleconnections are vast. The exact
14:29
same reshuffling of heat that causes drought
14:31
in eastern Australia will simultaneously bring
14:34
torrential flooding rains to the arid deserts
14:37
of South America. It alters the timing and intensity
14:40
of the monsoons in South Asia, which directly
14:43
impacts the food supply for billions of people.
14:46
Our sources even point out that it messes with
14:48
hurricanes on the other side of the planet. Oh,
14:50
absolutely. El Nino alters the high altitude
14:52
winds over the Atlantic Ocean, creating wind
14:56
shear that basically rips hurricanes apart before
14:58
they can form, leading to a quieter Atlantic
15:01
hurricane season. Right. But La Nina. La Nina
15:04
removes that wind shear, allowing Atlantic hurricanes
15:07
to become supercharged. An ocean temperature
15:10
shift off the coast of Peru can dictate whether
15:13
a hurricane hits Florida. It highlights how fluid
15:16
and connected the Earth's systems are. But, you
15:19
know, if you want to fully understand the extremes
15:21
of Australian weather, the Pacific is only half
15:24
the story. There's more. The atmosphere doesn't
15:26
care about the lines we draw on maps. There is
15:28
another major ocean pattern happening simultaneously
15:31
on the western side of the continent. We have
15:33
to look at the Indian Ocean Dipole, or the IOD.
15:36
Okay, so a different ocean, but a similar kind
15:38
of seesaw. How does the Indian Ocean Dipole operate?
15:41
It operates on the same basic thermodynamic principles,
15:44
just on a slightly smaller geographic scale.
15:47
The IOD measures the temperature difference between
15:50
the western Indian Ocean over near the coast
15:53
of Africa and the eastern Indian Ocean, situated
15:55
near Indonesia and Australia. So what does a
15:58
positive phase of this dipole look like? In a
16:01
positive IOD phase, the water near Africa becomes
16:04
warmer than average, and the water near Australia
16:07
becomes cooler than average. Okay, and cooler
16:10
water means? Cooler water means less evaporation.
16:13
Less evaporation means there is significantly
16:15
less moisture rising into the atmosphere to form
16:18
rain clouds that would normally sweep across
16:20
Australia from the west. So it dries things out.
16:23
The result is a suppression of rainfall, bringing
16:25
severe dry conditions, particularly to the southeastern
16:29
parts of Australia. And conversely, a negative
16:31
IOD means warmer water pools closer to Australia,
16:34
pumping vast amounts of moisture into the air
16:37
and leading to much wetter conditions. Exactly.
16:39
But the real devastation happens when you realize
16:41
these two oceans, the Pacific on the east, the
16:43
Indian on the west, are acting on the same landmass
16:46
at the same time. That's when things get truly
16:49
bad. Think about it this way. Having an El Nino
16:52
year is like having a truly terrible day at work.
16:54
You're stressed, your resources are depleted,
16:57
things are dry. But a positive IOD is coming
17:00
home from that bad day at work to find you also
17:02
have a flat tire. The two events compound each
17:06
other to make the situation catastrophic. That
17:09
synthesis perfectly describes Australia's darkest
17:11
climate moments. When those two systems lock
17:14
into their dry phases simultaneously, the continent
17:17
is essentially starved of moisture from both
17:19
sides. Both sides. Look at the millennium drought,
17:22
which crippled Australian agriculture from roughly
17:24
2001 to 2009. That was driven by a relentless
17:28
sequence of El Nino and neutral years, with virtually
17:31
no wet La Nina years to break the cycle and refill
17:34
the soil moisture. And the sources specifically
17:36
highlight the Black Summer bushfires of 2019
17:38
and 2020. Black Summer is the textbook example
17:41
of a compound disaster. How so? The continent
17:44
had already endured years of background drought,
17:46
so the vegetation was critically dry. Then a
17:49
remarkably strong positive IOD materialized,
17:52
shutting off moisture from the West, while the
17:54
Pacific also leaned dry. completely dry from
17:58
all directions. It created an environment where
18:00
the fires burned with an intensity and scale
18:02
that was historically unprecedented. Then in
18:05
a total whiplash event from 2020 to 2022, the
18:08
system flipped and delivered three consecutive
18:11
La Nina years, which the sources note is statistically
18:15
very rare. Highly unusual. It wasn't just a heavy
18:18
rainy season. It was a relentless multi -year
18:21
soaking where the soil couldn't absorb another
18:23
drop. The rivers had nowhere to drain, culminating
18:27
in the massive catastrophic floods across New
18:29
South Wales and Queensland. The damage from both
18:32
ends of the spectrum runs into the billions of
18:34
dollars, not to mention the immense human and
18:36
ecological toll, which makes predicting these
18:39
shifts one of the most critical scientific endeavors
18:41
on the planet. Given the destruction these compounding
18:44
ocean patterns cause, the logical next question
18:46
is, How do we defend ourselves? Like, how good
18:49
is our crystal ball? Well, we have vast institutions
18:51
dedicated entirely to this. The Bureau of Meteorology
18:55
continuously monitors these oceans and publishes
18:58
seasonal outlooks. Right. Underpinning that is
19:01
the CSIRO, Australia's National Science Agency,
19:05
conducting the deep research into how these systems
19:08
behave. Since the 1980s, the physical infrastructure
19:11
has improved exponentially. Like satellites and
19:14
things. Yeah. We have arrays of moored buoys
19:16
plunging into the deep ocean, fleets of autonomous
19:19
gliders, and satellites measuring sea surface
19:22
height and temperature down to the millimeter.
19:24
With all that hardware, you'd think we could
19:26
predict this perfectly. But the sources outline
19:28
a major limitation called the autumn predictability
19:30
barrier. What exactly is that? It is a notoriously
19:34
difficult window for meteorologists. During the
19:37
Australian autumn months, roughly March through
19:39
May, the temperature gradients across the tropical
19:41
Pacific are at their weakest. So they're not
19:43
strongly leaning one way or the other. Exactly.
19:46
The system isn't strongly anchored in either
19:48
El Nino or La Nina. Because the ocean and atmosphere
19:51
aren't tightly coupled together during this window,
19:54
the entire system becomes highly volatile. meaning
19:57
it can change quickly. It is incredibly susceptible
19:59
to being tipped in one direction or the other
20:02
by completely random short -term weather events,
20:05
like a random burst of spring storms. So a forecast
20:08
made in April about what will happen in December
20:10
is inherently less reliable than a forecast made
20:14
in August. Exponentially less reliable. And this
20:16
brings us to the fundamental truth about predicting
20:18
the weather. The Earth's climate. is a chaotic
20:22
system. When you say chaotic system, you mean
20:24
chaos theory. The classic idea of a butterfly
20:27
flapping its wings in Brazil causing a tornado
20:30
in Texas. The butterfly effect is the perfect
20:32
way to understand it. In a chaotic system, the
20:36
future state is highly, almost unimaginably sensitive
20:39
to tiny, unmeasurable differences in the initial
20:42
starting conditions. Okay, so if one number is
20:44
slightly off... Exactly. If our satellite reading
20:47
of the ocean temperature is off by just a fraction
20:49
of one degree... Or if a wind speed measurement
20:51
misses a small gust, that microscopic error multiplies
20:55
over time in the computer models. Within a few
20:58
months, that tiny uncertainty cascades into a
21:00
completely different forecast. So, what does
21:03
this all mean? If the system is chaotic and prone
21:06
to tiny errors, how do scientists provide any
21:09
useful warnings to farmers or firefighters? They
21:12
don't try to predict one perfect future. They
21:15
use a technique called ensemble forecasting.
21:17
Ensemble forecasting. Instead of running one
21:20
single computer simulation, they run dozens,
21:22
sometimes hundreds, of separate simulations of
21:25
the ocean and atmosphere. But for each simulation,
21:28
they slightly tweak those initial starting conditions.
21:31
Oh, I see. They change the wind speed by a fraction
21:33
or bump the ocean temperature up by a hundredth
21:36
of a degree. They intentionally inject the chaos
21:38
to see what happens. They run a hundred different
21:40
parallel universes to see where they all end
21:42
up. And then they look at the consensus. If 90
21:46
out of 100 simulations agree that the warm pool
21:48
is going to slosh east and form an El Nino, forecasters
21:53
have high confidence to issue a warning. But
21:55
if they don't agree? If the simulations are scattered
21:57
everywhere, some predicting El Nino, some La
22:00
Nina, some neutral, that widespread tells forecasters
22:04
that the system is currently too chaotic to call.
22:07
That uncertainty is honest, valuable information
22:10
in itself. Which means scientists aren't predicting
22:13
exact raindrops for a specific Tuesday in November.
22:17
They are basically counting cards at a casino.
22:20
that's exactly what they're doing they are looking
22:22
at the deck the ocean temperatures the wind speeds
22:25
the computer models and they are telling water
22:27
authorities and grain growers the deck is heavily
22:31
stacked for a dry season we can't guarantee you'll
22:34
draw a bad hand but you have a significant mathematical
22:37
edge if you prepare for drought and that mathematical
22:39
edge dictates major economic decisions Grain
22:43
growers use those probabilistic outlooks months
22:45
in advance to decide if they should plant drought
22:47
-resistant crops. And water management too, I
22:49
imagine. Yes. Water authorities use them to calculate
22:52
whether they need to hold on to reservoir water
22:54
or if they can safely release it for irrigation.
22:57
Fire agencies use them to position aircraft and
23:00
crews before a single dry lightning strike even
23:02
hits the ground. It's incredible to pull back
23:04
and realize that a farmer's decision about planting
23:07
wheat in rural Australia is fundamentally linked
23:10
to a microscopic temperature change in a patch
23:13
of water thousands of miles away near South America.
23:16
When you look out at a flooded river or a parched,
23:19
dusty paddock, you aren't just looking at local
23:22
weather. You are witnessing the visible, on -the
23:25
-ground consequences of a vast, invisible conversation
23:28
between the wind and the water across the entire
23:31
Pacific basin. It is a brilliantly complex machine.
23:35
And we must also acknowledge the critical context
23:38
of climate change here. A warming planet is injecting
23:41
more energy into this entire system. How that
23:44
excess heat will affect the frequency or the
23:46
sheer intensity of future El Nino and La Nina
23:48
events remains an area of intense, unsettled
23:51
scientific investigation. Because the models
23:53
aren't totally clear yet. The models show varying
23:55
projections, so maintaining honest scientific
23:57
caution while researchers gather more data is
23:59
the only responsible approach. It is a system
24:02
we are still learning to read. Which brings me
24:04
to a final thought I want to leave you with today.
24:07
Our sources mention that the CSIRO doesn't just
24:10
look at satellites. They study ancient coral
24:13
reefs and tree rings to map out how ESO behaved
24:17
centuries, even millennia, before the Industrial
24:20
Revolution. Yeah, that historical data is amazing.
24:23
It really is. Corals lock in chemical signatures
24:26
of ocean temperatures in their growth rings.
24:29
So if scientists can read these ancient records
24:31
and see the massive extreme El Nino patterns
24:34
that happened a thousand years ago. What if we
24:37
use that ancient data to completely redesign
24:39
our modern agriculture? Wow. That's an interesting
24:42
idea. Right. Instead of just planning our farms
24:45
and water systems around the weather of the last
24:47
50 years, what if we build our food infrastructure
24:49
to withstand the massive extremes that the coral
24:51
tells us are physically possible? Are we hobbling
24:54
our preparation for the future by ignoring the
24:56
deep past? It's a profound question. The blueprint
24:59
for what the Earth is capable of is written in
25:01
the natural world. It just depends on how boldly
25:03
we choose to read it. So the next time you see
25:05
a dusty summer sky or a relentless spring downpour,
25:09
remember. You are looking at the final act of
25:12
a story that started with the wind halfway across
25:15
the world. Thank you for joining us on this deep
25:17
dive. Until next time.