- 3 weeks ago
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00:00Every morning, I check the weather, but lately, I find myself wondering what's even normal anymore.
00:21Whew, it's windy.
00:23A powerful storm system is behind a surge of tornado activity.
00:26Breaking rain is flooding entire towns.
00:28B.C. is in a state of emergency as wildfires continue to grow.
00:33As people fled for their lives, the fear was there would be nothing to return to.
00:38It's hard to know what's coming.
00:40Here in B.C., the wildfire season is getting longer, more intense, and harder to predict.
00:46And the smoke doesn't always stay local.
00:48It can drift all the way across the continent.
00:51We can all see the weather's getting more intense, and I want to understand what's setting it in motion.
00:57So I'm meeting the scientists who study the invisible, yet powerful, forces that are driving extreme events.
01:04Could shifting air currents make a heat wave worse?
01:07It was so unprecedented to have temperatures that were that high.
01:11How do rising temperatures affect volcanoes?
01:14Oh, my gosh.
01:16If one system changes, could it throw off the weather somewhere else?
01:20What happens in the Sahara is connected to our daily lives here in North America.
01:25And just how far could shifts in weather reach?
01:29It will have implications for the wider ocean and the globe itself.
01:33This is a story about how currents flowing through the ocean, the atmosphere, and even deep in the ground are triggering wild swings in weather.
01:41Miami is on the front lines of an increasingly chaotic forecast.
01:55Behind the scenes, meteorologists like Larissa Abreu have to deconstruct what's going on with local weather every single day.
02:03This has been the headliner across the weather department.
02:07We continue to watch the storm.
02:09These storms are getting scarier.
02:11They're getting stronger.
02:13They're more intense.
02:14When we're talking about extreme weather, I make sure I leave no stones unturned.
02:20The more you understand the science, the better and more accurate your delivery is.
02:25This sometimes is life or death, but you have to deliver it because at the end of the day, you can't stop the weather.
02:33Does it seem like there are more extreme weather events now than when you started work here?
02:37100 percent.
02:38Being here in South Florida, I think that that is all people talk about.
02:43And it's a coastal community, so you see the impacts of climate change more with disappearing shorelines, with hurricanes, with intense rain, with heat, with flooding.
02:54And so there are definitely more extremes in the weather department.
02:58I'm from the West Coast, and our extreme weather is about heat domes and forest fires and smoke and atmospheric rivers.
03:06I mean, all of these are unusual, but they're becoming more frequent.
03:10So every year, we continue to break records as far as temperatures.
03:16And this year has been Earth's warmest year on record.
03:20Unfortunately, we've seen that happen the year before that as well.
03:25There's so many impacts with extreme heat and how it's a domino effect in so many ways.
03:34A heat advisory that's locked in place.
03:36The changes to the extreme summers that the southeast are seeing, to the huge and strong storms that we continue to see every year in the Atlantic, are all related to the warming in the Arctic.
03:48I mean, it's all connected.
03:53The Arctic is a long way from Miami, but it's amplifying extreme weather here and across much of the planet.
04:01To understand how it can have such a wide-ranging impact, a team of German scientists launched the largest polar expedition ever.
04:10The Arctic is absolutely key for the global climate.
04:14It's the epicenter of global warming.
04:16No other place of our planet does warm as rapidly as the Arctic.
04:21It's three times, perhaps four times faster in the Arctic than in the rest of the world.
04:25And that has severe implications for weather and climate in the northern mid-latitudes where we live.
04:32The expedition involved freezing their ship into the ice and spending a year investigating what could be speeding up the warming.
04:40One factor stood out.
04:42The Arctic has lost nearly a third of its summer sea ice.
04:46And that's triggering a feedback loop called the albedo effect.
04:50The rapid decline of the sea ice in the Arctic is directly relevant for climate and weather in our latitude.
04:56That is because when the sea ice declines and retreats, then you get a dark ocean surface.
05:03There you previously had a white surface of the ice.
05:05That dark ocean can absorb much more of the sunlight, of the energy coming from the sun, and it amplifies the warming.
05:13Bright ice reflects most of the sun's energy.
05:16But as the ice melts, the darker ocean is exposed.
05:20And that surface absorbs heat instead of bouncing it away.
05:23The more it melts, the faster things heat up.
05:27It's like swapping a white shirt for a black one on a hot day.
05:30You heat up faster.
05:31And if the Arctic is now warming more rapidly than the rest of the planet,
05:37the temperature contrast between the cold Arctic and the warming with latitudes will reduce.
05:43And the jet stream becomes less stable.
05:46And that is connected to extreme weather.
05:49The jet stream is a fast-moving river of air that flows in a fairly steady path
05:54when there's a strong contrast between the cold north and the warm south.
05:58But with that contrast breaking down, Larissa is watching things closely.
06:03How influential is the jet stream on the weather that we see?
06:06It is extremely influential.
06:08The jet stream is a column of air, and it basically drives our weather in this country from west to east.
06:16So this is an area of high pressure that we're watching here.
06:18It's the jet stream, and it's bringing in some rain out towards the Pacific Northwest
06:23and even western portions of Canada.
06:26It influences the weather we see every day.
06:28But the jet stream itself is shaped by huge, invisible forces
06:32that atmospheric scientists like Rachel White are working to decode.
06:37These things are happening at such a scale above our atmosphere
06:41that it's really hard to wrap our heads around.
06:44Yeah, it's happening at the top of the troposphere.
06:47We're like, whoa, 10 kilometers above the Earth's surface?
06:49And so the jet stream's roughly about the height of where airplanes fly.
06:56And so it actually means it does impact the speed at which planes can go.
07:00And the speed of the jet stream depends on the temperature difference
07:04between the Arctic and the equator.
07:07If you have a bigger difference between your equator and your pole,
07:11you'll have a stronger jet stream in the middle.
07:13But if you have a weaker difference, then you're going to have a weaker jet stream.
07:17The thing that climate change is doing, if you look at the surface temperatures,
07:22is the Arctic is warming so much faster than the equator.
07:26Because we're weakening this equator-to-pole temperature gradient,
07:30we're going to weaken the jet.
07:31That's going to create more waves.
07:33We're going to see more extreme events.
07:35To show how waves in the atmosphere shape what happens on the ground,
07:38Dr. White and her team map real-world data onto a pretty unique projector.
07:43This one is showing us the jet stream and surface temperatures at the same time.
07:48So the jet stream is the white band typically moving from west to east.
07:53And sometimes they stop moving and they become sort of what we call quasi-stationary.
07:58And that's what happens in some of these extreme events
08:00and can lead to these extreme temperatures.
08:03And so this is part of Lualawi's research,
08:05is trying to understand these quasi-stationary waves.
08:08Let's stop and unpack quasi-stationary.
08:11The jet stream isn't just for planes.
08:14It moves weather along, like a high-speed highway.
08:17But when there's a sharp bend, traffic slows and the weather can get stuck in place.
08:22Climate change is making these atmospheric traffic jams
08:25three times more common and more deadly.
08:29This is what happened during one of the most extreme weather events of my lifetime.
08:33On this one, we have the 2021 Pacific Northwest state wave.
08:38And you'll see the jet stream cuts off and almost becomes a circular around that region.
08:43Those red colours, those are showing temperature anomalies during the event.
08:47And when you are contained in that circle, actually, you also don't see any clouds
08:50because weather is almost not allowed in that region.
08:54Certainly for those of us who were there and lived through it,
08:57it really felt like you were suffocating.
09:00There was nowhere to go.
09:02We broke temperature records for three days in a row.
09:06On the fourth day, the town of Lytton burned to the ground.
09:10Over 600 people died in B.C. alone.
09:12I mean, this was unbelievable times.
09:16That's what these atmospheric blocks are doing.
09:19That the longer this atmospheric circulation sits in this wavy configuration,
09:26the worse those extreme events can get.
09:29But interestingly, it's the same sort of atmospheric circulation pattern
09:33that causes cold extremes.
09:35A historic winter storm brings Texas to a standstill.
09:39Dozens of deaths were reported, many from hypothermia.
09:42On this other plot, we're looking at the Texas cold snap
09:46that happened in February 2021.
09:49There was a lot of power out of this
09:50because when such events happen in regions that are not used to it,
09:54there's no infrastructure to deal with these kinds of events.
09:57A cold wave is so rare in Texas.
10:01And you can see that as the jet stream passes through this North America region,
10:05by meandering like that, this jet stream is bringing cold air from the poles.
10:10Here, the purple colors are very low temperatures
10:12with respect to what we see regularly or on average.
10:15And it was a very significant event.
10:18Looking at it from here, you really can see how connected everything is.
10:22Like it's all one system.
10:24Exactly. All of it's connected.
10:27Jet streams do more than just carry storms.
10:30They also move dust from one side of the world to the other.
10:34Here on a rooftop weather station in Florida,
10:39atmospheric chemists are tracking these particles
10:41and their surprising impact on temperatures.
10:45When we think about climate change, at least,
10:47I don't think about dust and particles in the air,
10:50but that is such a big part of what you do.
10:53Yes, and dust has been a real big player
10:55in many different facets of Earth's climate.
10:59On dusty days, we don't get as much visibility.
11:03Well, that also affects, you know, the temperature that we experience, right?
11:06When it's a clear day right now, it's quite warm.
11:09But on a dustier day, we might not get as much sun affecting us.
11:15Dust is kind of like sunscreen.
11:17It blocks some of the harmful rays, and this cools things down.
11:21But not all dust is the same.
11:23And Dr. Gaston is especially interested in the type
11:26that travels all the way from the Saharan Desert.
11:29What happens in the Sahara is connected
11:31to our daily lives here in North America.
11:35You have intense heating of the North African continent.
11:39This lifts dust from the Sahara Desert into the atmosphere.
11:43The Saharan air layer, once it gets lofted,
11:46gets pushed across the Atlantic Ocean due to the jet.
11:50And because it's high up in the atmosphere,
11:53as it transports across the Atlantic Ocean,
11:56it descends slowly,
11:58and that's how it's able to make its way
12:00all the way across into the Amazon rainforest.
12:03It's like a fertilizer,
12:05and it can stimulate plants
12:07that then take carbon dioxide out of the atmosphere.
12:11The climate system impacts how much dust is in the atmosphere,
12:15and then the dust in the atmosphere
12:17in turn impacts the climate system.
12:20Since dust plays a powerful role in shaping temperatures,
12:23Dr. Gaston and her team want to know whether it's reaching Miami.
12:28What we can do with the tower is,
12:30this is a high-powered pump
12:32that can actually suck air out of the atmosphere.
12:35We try to piece together where these particles are coming from.
12:39Is the particle coming from the ocean?
12:42Is it coming from the Sahara?
12:44Is it coming from the causeway?
12:46And in my lab,
12:47we can get an assessment of what's in the air.
12:50This is blowing my mind.
12:52I never knew there were so many different types of dust.
12:55So basically what you're telling me
12:56is you're a chemical detective.
12:58Is that right?
12:59Yeah, that's exactly right.
13:02So we've measured the dust going back to the 1960s,
13:06and we have seen shifts in how much dust
13:10comes to the Caribbean and to the Americas.
13:12When we have changes in air currents and pressure systems,
13:15it can shift the dust such that it doesn't go to the Amazon.
13:19That could really reduce how much carbon gets absorbed by the Amazon.
13:24We'd have an increase in warming.
13:27Like any good detective story,
13:29the tale of Saharan dust has a scary twist.
13:32When it drifts off its usual path,
13:34it's bad news,
13:35not just for keeping temperatures down,
13:38but for hurricane season too.
13:41Storms require a lot of moisture.
13:44And so when that desert air interacts with a brewing storm,
13:48it can suck some of that moisture out of it,
13:51and that can possibly diminish the storm.
13:53So we were in Barbados when hurricane Beryl hit.
13:57We had a big dust cloud coming,
13:59and at first people thought,
14:01well,
14:01the dust should suppress the storm from intensifying too rapidly.
14:06But what happened was we had a rain event.
14:08It washed the dust out of the atmosphere,
14:11and it facilitated Beryl spinning up
14:13and intensifying into as bad of a storm as it was.
14:16Beryl wasn't just destructive.
14:20It made history as the earliest Category 5 hurricane the Atlantic has ever seen.
14:26Storms are now getting much worse, much faster.
14:29This is the world's largest hurricane simulator,
14:32and scientists are using it to investigate what's driving storms to these new extremes.
14:37Here we focus on what happens where the two fluids that are so important on our planet,
14:43how the air and the water mix.
14:45So a lot of things that are really important for weather
14:47have to do with how those two things interact.
14:50So air and water, they interact all the time,
14:54but we can't really see what's going on.
14:57And so it's so helpful when you have a modeling system like this
15:01where you can visualize it.
15:02So can you walk me through a Category 5 class hurricane?
15:07When we turn on our fan, you'll see that the wind will start to cycle up
15:12and the waves will start at the front and start to grow.
15:19It's probably about a Category 1 now.
15:22Wow, look at that spray.
15:30For a hurricane to grow, first of all, you need warm water
15:33that is heating the lower atmosphere and evaporating water.
15:37And you need all the other atmospheric conditions to be right.
15:41It needs to be kind of an unstable condition
15:43where you have the air can start rising
15:45and there's not a lot of dry air in the atmosphere
15:48like from the Saharan Desert.
15:50If all the ingredients are in place,
15:52that rising air starts rotating and can grow into a hurricane.
15:59Well, this is a Cat 5 now.
16:01The simulator cranks the wind to 300 kilometers an hour.
16:10It's the only one in the world to reach this speed
16:13and it shows how sea spray adds heat and moisture
16:31to supercharge a hurricane.
16:33To get up to the Category 5,
16:34there'll be a tremendous amount of spray in the air
16:36and almost continuous breaking of the waves.
16:40In the ocean, you can go from a tropical storm
16:43to a Category 5 hurricane in just over a day.
16:46And that is called rapid intensification.
16:49Your house may lose the roof,
16:51maybe destroy yourself, but you may still survive.
16:53But if you have 10 feet of water in your home
16:57and you don't have any way to get out,
16:58it's really hard to survive that situation.
17:01What's terrifying isn't just their strength.
17:05It's how fast hurricanes are intensifying.
17:08It's even shocking veteran meteorologists.
17:11Hurricane Milton has been rapidly intensifying already.
17:15John Morales, his demeanor while reporting the weather
17:19has always been cool like a cucumber.
17:21And so to see that man with such a legacy break down
17:26because he understood the severeness
17:29of Hurricane Milton at the time,
17:32I think it struck a chord with many.
17:34It has dropped 50 millibars in 10 hours.
17:40Um, I apologize.
17:42This is just horrific.
17:46Where the storm was in that particular moment,
17:48it was hitting an area
17:50that they have just basic necessities,
17:53not an area that has the infrastructure
17:55to withhold and survive a Category 5 storm.
18:01Rapid intensification is becoming more common,
18:04mostly because there's a lot more warm water out there.
18:06You have more warm water,
18:07you have more potential energy there
18:09that the hurricane can grow on.
18:11Hurricanes are now intensifying
18:13over the hottest oceans on record.
18:16But the ocean's role in driving extreme weather
18:18doesn't stop there.
18:23As a marine biologist,
18:24I've always been focused on looking down into the water.
18:27But learning how ocean currents affect weather
18:30makes me think about what's happening above.
18:34Brad DeYoung is studying how currents are changing
18:36and what that means for the forecast.
18:39So the ocean obviously drives the atmosphere
18:42both in heating and cooling it.
18:44And if you don't know the ocean,
18:46then you can't include that in your weather forecast.
18:49Forecasting used to rely mostly on data from the skies.
18:53But the atmosphere shifts so quickly
18:55that predicting anything beyond a few days
18:57was unreliable.
19:00Up until about a decade ago,
19:02it was impossible to make a weather forecast
19:04longer than about five days.
19:06You can now get forecasts to between seven and ten days.
19:09The reason is we have a whole program
19:11of these autonomous floats
19:13providing the ocean information
19:15that allows you to see beyond the five-day window.
19:21I joined the Department of Fisheries and Oceans Canada
19:24to launch instruments
19:25that track how the ocean moves heat
19:27and shapes the weather.
19:29The gear's high-tech,
19:31but surprisingly simple to launch.
19:34You'll pick it up
19:35and you'll just kind of dump it in.
19:37Yeah.
19:39There's a program called Argo
19:40with almost 4,000 floats.
19:45They're measuring mostly temperature and salinity.
19:48This program has already collected more data in 10 years
19:53than all oceanographers did in the previous century.
19:58Perfect.
19:59Wow.
20:00That's how you do science.
20:01Sciencing.
20:02We also use ocean gliders,
20:06which look like torpedoes.
20:09And so all these cool technologies
20:11allow us to make measurements
20:13that even 20 years ago
20:15were just undreamt of.
20:17How have things changed over those 20 years?
20:20Well, the big story is
20:21the ocean has absorbed about 90% of the heat
20:25as a result of global warming.
20:27So most of the heat isn't in the atmosphere.
20:29This is a huge finding.
20:33With the ocean absorbing so much extra heat,
20:36the effects are far-reaching.
20:38While the jet stream acts like a highway for weather,
20:41ocean currents work more like conveyor belts,
20:44moving heat slowly around the planet.
20:47One of the most powerful is the AMOC.
20:49It's moving more than 100 times
20:52all of the energy production of all humans
20:54everywhere on the planet
20:55from everything we have,
20:57electric power plants and you name it.
20:59And it's doing that every year.
21:02You slow that down by even 10%
21:05and that's still 10 times the energy production of humans.
21:08So small changes can have big impacts.
21:11Billions of people would feel these impacts.
21:14If the AMOC moved less heat,
21:17weather could be disrupted across the planet.
21:20Short for Atlantic meridional overturning circulation,
21:24the system includes the Gulf Stream,
21:26which carries warm water northward.
21:29There, it cools, sinks into the deep ocean
21:32and flows back south.
21:34The AMOC is what keeps Europe milder
21:36than it would be otherwise.
21:38To show what's driving the circulation,
22:04oceanographer Didier Swingadu set up a simple demo.
22:07Using warm and cold water.
22:10Cet aquarium représente en fait l'océan.
22:13Depuis les tropiques, ici,
22:17jusqu'au pôle, représenté ici.
22:20Vous avez du froid ici,
22:22du chaud ici.
22:25Et donc c'est cette différence de densité
22:28qu'on appelle un gradient
22:29qui va générer le courant.
22:31As the water cools down,
22:33it sinks because it's denser than warmer water.
22:36And that sinking helps power the global conveyor belt.
22:40But Arctic warming is changing the balance
22:42as the surface ocean is becoming less cold
22:45and less salty.
22:48The Arctic milk water is releasing fresh water
22:51into the surface ocean.
22:52If you add too much fresh water,
22:54then the water never gets dense enough to sink
22:57and so that stops happening.
23:00And then that changes the way in which
23:01the whole ocean circulation develops.
23:05The AMOC is under pressure
23:06and tracking such a big system is hard.
23:09Scientists don't yet know
23:11when all this fresh water
23:12might jam the planet's conveyor belt
23:14or how bad it could be.
23:17But one key place
23:18could hold important clues.
23:20The Florida Straits.
23:21Between Miami and the Bahamas,
23:23the Gulf Stream flows through
23:25a narrow channel at full force.
23:27The Gulf Stream contains the water
23:32that eventually will overturn
23:34in the northern North Atlantic.
23:35If the Gulf Stream is weakening,
23:38that's a sign that the overturning is weakening.
23:41Oceanographer Lisa Beal
23:43is leading a study
23:44that deploys ocean moorings evenly
23:46all the way across the Florida Straits.
23:49She's searching for signs
23:50that the current might be shifting.
23:52Whenever you put anything
24:04at the bottom of the ocean, right,
24:05it has to withstand a lot of pressure.
24:08These things sit at the bottom
24:09of the Florida Straits
24:10in hundreds of meters of water.
24:13So this instrument,
24:15it has a current meter
24:16that measures the velocity of the water
24:18as it flows past the instrument.
24:20We have them all programmed
24:21to send 16 pings
24:23to the surface every 10 minutes.
24:25So it's really
24:26a very high volume of data, yeah.
24:29No kidding.
24:30We usually go on
24:32the University of Miami vessel,
24:33the Walton Smith.
24:35So that's how we've been
24:37taking out our instruments
24:38and laying them in the Florida Current.
24:41Half of our instruments
24:42are actually in Bahamian waters,
24:44and that feels really special to me.
24:46I grew up in the Bahamas,
24:47and when I was 50,
24:49and my island was destroyed
24:51by Hurricane Joaquin,
24:52and that was a pivotal moment for me,
24:54and it helped kind of inspire
24:55this desire to work
24:57in the climate change space
24:58to help my country.
24:59So do you feel empowered
25:01to make that difference
25:02and to be part of that change?
25:04Yeah, definitely.
25:05And for me,
25:06this research is really important
25:08because it helps us understand more
25:10about how changes in the Florida Current
25:12are really impacting
25:13those day-to-day flooding,
25:15sea-level rise events
25:16in both countries.
25:18It often floods here
25:20even when it hasn't rained,
25:22something known
25:23as sunny-day flooding.
25:25In Miami,
25:26we don't always know
25:27when to expect, you know,
25:28really bad flooding
25:29because it's not just the tides,
25:31but the strength of the Gulf Stream,
25:33and the amount of heat it's carrying
25:34can also change sea level.
25:37The sea surface
25:38is about a meter higher
25:40in the Bahamas
25:41because of the Gulf Stream.
25:42So they wouldn't have
25:43the same rise in seawater.
25:45Exactly.
25:47Strength of the current
25:48is proportional
25:49to the difference in sea level
25:51between Miami and the Bahamas.
25:53We have the lowest sea level,
25:55so you can imagine
25:56if the current weakens,
25:57then the sea level
25:59could go up at the coast.
26:01And so we're trying
26:02to understand that aspect more.
26:05With a flood of new ocean data
26:07pouring in,
26:08leading climate modeler
26:09Ben Kurtman
26:10analyzes how ocean systems
26:12could change
26:12in the decades ahead.
26:15This is a server room.
26:17These are all data disks.
26:18Each one of these
26:19is just grinding away.
26:22So this picture
26:23is just showing you
26:25surface current speeds.
26:27This ribbon,
26:28that's the Gulf Stream.
26:29You see these less bright colors.
26:31The current is weaker than normal.
26:33And our estimates
26:34seem to suggest
26:35that we're going to see
26:36a reduction in the strength
26:37of that Gulf Stream
26:38associated with a weakening
26:40trend of the AMOC.
26:42So if the Gulf Stream
26:44starts to weaken,
26:45Yeah.
26:45And the currents around here
26:47start to weaken,
26:48sea level is just
26:49going to keep going up?
26:50Sea level rise continues.
26:52Coastal flood risk goes up,
26:53and then you combine that
26:54with the ice sheets melting,
26:56you've got yourself
26:57a perfect storm.
26:57So there's a Hollywood film
27:01called The Day After Tomorrow.
27:02In it, they say,
27:04okay, the AMOC has shut down.
27:06Is this at all likely?
27:08Not as far as that clearly.
27:10The time scales of the movie
27:12obviously required them
27:13to have that happen within days.
27:15And some of the results
27:17they showed were absurdly
27:19non-physical,
27:20massive water inundation
27:22of Manhattan.
27:24But I think reasonably likely
27:25are just really an acceleration
27:27of the patterns
27:28we've already been seeing.
27:30Extreme rainfall events,
27:32dramatic changes
27:33in hurricane patterns.
27:34It basically would shift
27:36the whole structure
27:37of our expectations
27:38for weather and climate,
27:40in the Atlantic in particular,
27:41but also around the planet.
27:45When the AMOC collapses
27:46in the movie,
27:47the North freezes
27:48almost overnight.
27:50In real life,
27:52changes would take decades.
27:53But if the odds of a plane crash
27:55were as high as this,
27:56no one would be flying.
27:59Turns out,
28:00the deep chill part
28:01isn't that far off.
28:11With the seasons
28:12a lot more marked
28:13than at the current time.
28:16A big effect
28:17on the temperatures
28:17which will remain cold.
28:24Then there are
28:24more high-scale consequences.
28:26The AMOC plays
28:27a lot of the position
28:28of the precipitation
28:29of the African-American moussons.
28:31So here,
28:31we're talking about
28:32a major impact
28:33in terms of agriculture.
28:35Because we'll have
28:35a diminution
28:36to 30% of the precipitation.
28:38So a major impact
28:39on the production
28:40of Sorgho,
28:40du Millet,
28:41which is a living culture
28:42for the people
28:43who live there.
28:45And we're talking
28:45about hundreds of millions
28:46of people.
28:51What happens
28:52in the Arctic
28:53clearly doesn't stay
28:54in the Arctic.
28:56Melting ice
28:56is flooding the ocean
28:57with fresh water,
28:59threatening the currents
29:00that have stabilized
29:00our climate
29:01for thousands of years.
29:03And the effects
29:04of melting ice
29:05don't stop there.
29:07They ripple
29:07through the atmosphere
29:08and down
29:09into the Earth itself.
29:10disturbing another
29:12powerful force,
29:13volcanoes.
29:23I've come to Mount Meagre
29:24to see how melting ice
29:26can trigger
29:26a local disaster.
29:28Here,
29:29a team from UBC's
29:30Landscapes of Climate Change Lab
29:32is studying
29:33a disappearing glacier
29:34on top of a restless volcano.
29:37And now we can start
29:39to see the fumaroles.
29:40Dominous.
29:42Wow.
29:43So this does look different
29:44to the last time I was here.
29:45The fumaroles are a lot more obvious
29:47and a lot bigger.
29:49A fumarole is just a volcanic vent
29:50as spewing gases.
29:53And we're going to land
29:53on the glaciers
29:55where those fumaroles
29:56are erupting
29:57from the surface
29:58of the ice.
29:59They've really melted
30:00through that glacier ice
30:02which has just gotten
30:03so much thinner
30:04with successive years
30:05of heat domes
30:06and heat waves
30:07and hot summers
30:08just really melting it down.
30:11And then we've been having
30:11milder and warmer winters
30:13so there's less accumulation
30:14and restoration
30:15of the glacier.
30:17Mount Meagre
30:18is the site
30:18of the largest known eruption
30:20in Canada
30:21and it's still one of the country's
30:23most dangerous volcanoes
30:24in part
30:25because of how many people
30:27live nearby.
30:28The community of Pemberton,
30:30the Lilwat First Nation,
30:31farms
30:32and critical infrastructure
30:33all sit downstream.
30:46We've landed in fresh snow
30:48on Mount Meagre.
30:49This place is amazing!
30:52It's beautiful
30:52but the volcano
30:54is more dangerous
30:55than it looks.
30:56The snow covers a landscape
30:57that's crumbling
30:58from the inside out.
31:00I'm going to walk
31:01in your tracks.
31:02Great idea.
31:04I'm totally going to face plant.
31:07As the glacier melts
31:09it's triggering
31:10a cascade of changes
31:11that make the mountain
31:12more unstable.
31:14The team uses a drone
31:16to map the growing hazards.
31:20There's a lot of emergence
31:21of these enormous crevasses
31:23that we can see
31:24just to the left.
31:25The geothermal heat
31:26from the vents
31:27that's also going to be
31:28contributing to that retreat
31:30of the ice,
31:30the warming of the landscape
31:31from the bottom up
31:33and creating these distinct forms
31:35that we're seeing today.
31:36Did you hear the rock fall?
31:37No.
31:38Oh no.
31:39Yeah, so you can see
31:40over the funeral
31:41the blue ice
31:42and there's a lot of debris
31:43because it's all kind of
31:45unraveling from the valley walls.
31:47Rocks are falling off.
31:48There's a volcano right here.
31:50I mean, there's a lot of energy
31:51going on.
31:52Yes.
31:53Absolutely.
31:53And they're all
31:54kind of intersecting.
31:56As these glaciers are thinning
31:57then the volcano gets to expand
32:00because it's under less pressure.
32:03So as it expands
32:04it allows for more movement
32:07of magma and gases to come out.
32:09So you're getting these feedback
32:11between what's triggering
32:12the volcanic activity
32:13and then what's triggering
32:15the glacial activity
32:16and the two of them are dancing.
32:21In Iceland
32:22glaciers that once stretched
32:24for kilometers are retreating
32:26and scientists fear
32:27this could trigger more eruptions
32:29with severe consequences.
32:31In 2023
32:33the town of Grindavik
32:35was evacuated
32:36and left nearly empty
32:37for years.
32:39For Freystein Sigmundsen
32:41it's part of a dangerous
32:42new chapter he's tracking.
32:44In my research
32:47on the volcanoes
32:48the biggest surprise
32:49has been how
32:50the climate change
32:51can actually influence
32:53volcanoes.
32:55The volcanoes
32:55were very gentle
32:56to the people of Iceland
32:58for half a century.
33:00But what has happened
33:01here in Grindavik
33:02was truly a shock.
33:05There has been no eruptive
33:07activity here
33:08for 800 years
33:09so now we have had
33:11in the last three years
33:12nine eruptions.
33:14Here in Grindavik
33:15most visual is
33:16all the lava
33:16that has partly
33:17flowed into town
33:19but actually
33:20most of the damage
33:21is due to cracks
33:22earthquakes
33:23and faulting
33:24so this is destroying
33:26houses and property.
33:28While homes here
33:30are torn apart
33:30by ground movements
33:32melting ice
33:32is reshaping the land
33:34on a much larger scale.
33:35We see that
33:37a very important
33:38effect of
33:39retreating glaciers
33:40is that they are
33:41causing uplift
33:42of the ground
33:43that we can measure
33:44one to few centimeters
33:46per year
33:46here in Iceland
33:47because there is
33:48less weight
33:49on the surface
33:50as the glaciers
33:51are thinning.
33:53This can change
33:54the pathways
33:54for new magma
33:55and it can also
33:57influence the timing
33:58of eruptions
33:59and in some cases
34:00volcanoes can collect
34:02more magma.
34:05If retreating glaciers
34:11can help wake up
34:12volcanoes in Iceland
34:13what does this mean
34:15for Mount Meagre
34:15in BC?
34:18About half its glacier
34:20has melted
34:20and shows no signs
34:22of stopping.
34:23And this was one
34:24of the trail cams
34:25from a couple of weeks
34:27ago so all of this
34:28area was full of ice
34:29and crevasses
34:30only two years ago.
34:32And now it's just
34:33all this dark
34:34colored debris.
34:34The harsh reality
34:36is it's disappearing
34:37before our eyes
34:38and permanently
34:39sometime soon.
34:42Is there anything
34:44unexpected that you've
34:45found because
34:46of the glacier melt?
34:47So we know
34:48that it is an active
34:49system.
34:50We know that there
34:51is movement happening
34:52beneath the surface.
34:54We know that
34:55the last eruption
34:56was two and a half
34:57thousand years ago
34:57and that eruption
34:59was of a similar
35:00size and scale
35:01to that of
35:02Mount St. Helens.
35:03Oh, now we've got
35:05an eruption
35:05down here.
35:07If another eruption
35:09happens again,
35:10you know,
35:10we could get
35:11an ash cloud
35:12which covers
35:13Vancouver
35:13and Seattle
35:14and we could
35:16have lava flows
35:17which devastate
35:18an entire area.
35:20Science can't
35:21yet predict
35:21exactly when
35:22the next big eruption
35:23will happen,
35:25so researchers
35:25are watching
35:26for warning signs.
35:27these big plumes
35:29that are kind of
35:29coming directly
35:30towards us,
35:30so I think we
35:31should mask up
35:32for a little bit
35:32just until this
35:33next plume passes.
35:35Based on current
35:36data, an eruption
35:37doesn't appear
35:38imminent, but melting
35:39ice is making the
35:40mountain more
35:41unstable, and that's
35:43setting the stage
35:44for a different
35:44kind of disaster.
35:46This volcanic
35:47complex was the
35:49site of one of
35:50the largest
35:50catastrophic landslides
35:52in human history.
35:54Basically, the volume
35:55of that peak that we
35:56can see behind us
35:57and it all just
35:58comes crashing down.
36:00On the ride back,
36:01we followed the
36:02path of the
36:03landslide.
36:05So the landslide
36:06was caused by
36:07an intense heatwave.
36:0950 million cubic
36:10meters of sediment
36:11came rushing down
36:13that mountain
36:13at over 200
36:15kilometers an hour
36:16and carved out
36:17this incredible
36:18flow path.
36:19And it went over
36:20100 to 200 meters
36:22above the face
36:24of the valley.
36:25It was just
36:25moshing everywhere.
36:27But for many years
36:28before that failure,
36:30all of these
36:31different conditions
36:32were generated.
36:33So the history
36:33of glacial retreat
36:34makes it a weak slope,
36:36a mountain of bush,
36:37but when the heatwave
36:38happened, that rock
36:39expanded.
36:40It was enormous,
36:42and the impacts
36:43on the landscape
36:44we can still see
36:45today, 10 years on,
36:46and we're going to be
36:47seeing the generations
36:48into the future.
36:50You can see also
36:51to the right,
36:52there's all of the
36:52agricultural land,
36:54right by the river.
36:55So again,
36:56when we're thinking
36:57about the cascading
36:58impacts of landslides
37:00and mass movements,
37:01we're thinking about
37:02how the flood risks
37:03to those communities
37:04are changing
37:05and evolving over time.
37:07When you start
37:07thinking about
37:08all the impacts
37:09from climate,
37:10you're like,
37:10you're kind of
37:11sitting right downstream.
37:12You know,
37:12as these events
37:13become more frequent
37:14because of climate change,
37:15it's so important
37:16that we understand
37:17their dynamics
37:18so that we can better
37:19predict, better warn,
37:21and build that resilience.
37:23This is the new normal.
37:24This is the new normal.
37:26And it's repeating
37:27across the planet,
37:28from the Himalayas
37:29to the Andes.
37:31When extreme heat or rain
37:33hits slopes weakened
37:34by glacial melt,
37:35the result is often the same,
37:38catastrophic landslides
37:39and floods.
37:41With communities
37:42struggling to keep up,
37:43scientists are racing
37:45to turn insight into action.
37:58Behind every forecast
38:00is data gathered
38:01by scientists
38:01from around the world.
38:04They're working
38:05to understand
38:05how shifting jet streams,
38:07ocean currents,
38:08dust patterns,
38:09and even magma
38:10are driving
38:11more extreme events.
38:13But behind all
38:14of this change
38:14is a powerful,
38:15invisible force,
38:17CO2.
38:18Emissions from cities,
38:20fires,
38:20and power plants
38:21have now hit record levels,
38:23and this will shape
38:24our lives
38:25for decades to come.
38:27This means scientists
38:28aren't just tracking change,
38:30they're studying
38:30how we adapt to it.
38:32If we stopped polluting
38:33CO2 and methane today,
38:35completely stopped,
38:35dead stop,
38:36there'd be 30 more years
38:38of warming.
38:40We're going to have
38:40to figure out
38:41how to adapt
38:41to the continual changes.
38:42Do your models
38:44help directly
38:46in community-level events?
38:48Yes.
38:49So, in fact,
38:49I say that emphatically.
38:51We're actually working
38:52to develop forecast tools
38:54that can tell
38:55the risk of fire outbreaks
38:57in the West,
38:58where that's going
38:58to be concentrated
38:59so that materiel
39:01and resources
39:02and personnel
39:03can be redeployed
39:05and advanced.
39:05On the shorter timescale,
39:07we're seeking
39:07to develop tools
39:08so that the forest fighter
39:10that's in the valley
39:11right now fighting
39:13that fire knows
39:1430 minutes from now
39:15the wind's really
39:16going to pick up,
39:16I've got to bug out.
39:17I love that
39:18because it doesn't end
39:19with the model.
39:20You're saying,
39:21this is what the data say
39:22and this is what
39:23we can do about it.
39:24That's right.
39:25If we use
39:25the best available science
39:27to guide where
39:28and how we build
39:30infrastructure,
39:31where and how we live,
39:32I'm very optimistic.
39:34Every scientist I met
39:37is looking to connect
39:38their data to daily life.
39:40Dr. Beal hopes
39:41to detect changes
39:42in the current
39:43early enough
39:44to help Miami prepare
39:45for sunny day
39:46flooding events.
39:48And at the hurricane simulator,
39:51Dr. House
39:51is contributing
39:52to the science
39:53that helps people
39:54survive deadly storms.
39:57Here we can make
39:58really detailed measurements
39:59that are difficult
40:00to make over the ocean
40:02and that particularly
40:03is important
40:04for the really high winds
40:05and the hurricanes.
40:06We can get the necessary data
40:08to do better forecasting,
40:09which is a life safety thing.
40:11And then there's
40:11a longer term thing
40:12about better construction planning,
40:14building and zoning
40:15for the damages
40:16that can occur
40:17so the communities
40:18can be more resilient.
40:20So climate change
40:22is having a very chaotic
40:24and interconnected impact
40:26on our natural systems.
40:29And some catastrophic landslides
40:30have claimed the lives
40:31of individuals.
40:32and there haven't been
40:34these management systems
40:36in place.
40:37But we can make a difference.
40:39We can put sensors
40:40on a mountain
40:41and track the seismic records
40:42of these rock falls
40:43so that when something
40:45really big comes down,
40:46we're prepared for that.
40:48And it only takes
40:49a small group of people
40:50to share knowledge
40:52and that stops a hazard
40:54from becoming a tragedy.
40:56To stay ahead of disaster,
40:58scientists are looking
40:59at how the pieces fit together,
41:01how one change
41:02in the landscape
41:03can ripple outward
41:04and trigger extreme events
41:06downstream.
41:07A lot of the research
41:09that my group
41:10has been doing
41:10has really been looking
41:11at what are those connections
41:13from the mountaintop
41:14to the ocean.
41:15So we're standing
41:16on the banks
41:17of the Lilluit River.
41:18Earlier,
41:19we were up on the glacier
41:20and that glacier
41:22is what's feeding
41:23this river here.
41:26That glacier shrinks,
41:28it fails,
41:28causes a landslide
41:29and that landslide
41:30sends a pulse of sediment
41:32that goes all the way
41:33downstream.
41:34And that increases
41:35the riverbed height
41:36and so there's
41:37more chance of flooding.
41:39It's almost like
41:40that flow never stops.
41:42No, it never does.
41:43There is no start
41:44and end to that flow.
41:45And the more we get
41:46to know the Earth's system,
41:47the more we realize
41:49that these connections
41:50are happening
41:50all the time.
41:52It's one thing
41:52to understand
41:53that everything
41:54is connected
41:55but it's another
41:56to actually feel it.
41:58Dr. Copps
41:59is taking that
42:00a step further.
42:01We've been using
42:02hydrophones
42:03to start to hear
42:05what is being transported
42:07from the mountaintops
42:08to the ocean.
42:09So both how much water
42:10is moving through the system
42:11and how much sediment
42:13is moving through the system.
42:15I've actually been
42:16collaborating with
42:17sound artists
42:18to create soundscapes
42:19where we're inviting audiences
42:21to actually listen
42:22to the stories
42:24that the Earth
42:24is telling us.
42:27Okay, I'm hearing
42:28like a sound.
42:30So that's the sand
42:32and silt
42:33that's being flushed
42:35down the river.
42:36Oh, okay.
42:37Right?
42:37So you can hear it.
42:38It's kind of like
42:38it's roaming through.
42:40Yeah.
42:41These hydrophones
42:42help understand
42:43in a more embodied way
42:45what are the impacts
42:46of climate change.
42:47So we're actually
42:48listening to the sounds
42:50of climate change.
42:51In order to be able
42:52to truly understand
42:54what we're losing
42:55as the Earth
42:56is adapting
42:57to a warmer planet,
42:58we need to be able
42:59to understand it
43:00through all of our senses.
43:03Now when I start my day,
43:05I pay more attention
43:06to shifts in the weather
43:08and how they connect
43:09to something bigger.
43:12As extreme events increase,
43:15it helps knowing
43:16there's a global effort
43:17to study the invisible forces
43:18that are reshaping our world.
43:20Because the more we understand,
43:22the better we can adapt.
43:25How we chat about the weather
43:27matters too.
43:28It's not just small talk anymore.
43:30It's about preparing
43:31for what's ahead.
43:38We'll see you next time.
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