Multiple speakers: Climate change is not only affecting the health of the planet.

It's also affecting human health.

Planet Earth.

We have a problem.

Absolutely.

We're in a climate emergency.

Climate change is doing more than just melting ice caps and bleaching coral.

It's making us sick.

Everybody is being impacted.

You name it.

Everything is changing.

The number one threat to humans.

Dr. Darragh OʻCarroll: Hi, my name is Dr. Darragh O'Carroll and I'm an emergency and disaster physician.

And I've seen the effects of climate change firsthand.

We're getting more extremes, not less.

Climate change is bigger than all of us.

That's when all hell is going to break loose.

Join me as I travel the globe meeting world experts as they sound the alarm, seeking solutions to some of the world's most pressing health issues.

Multiple speakers: Even going beyond two degrees is going to be catastrophic.

We still have a fighting chance, but we've got to move fast now.

Music: Darragh OʻCarroll:  In today's program, we head down under to the Great Barrier Reef to see how climate change is affecting one of the natural wonders of the world and what it means for human health.

We'll follow the deadly Irukandji jellyfish, one of the world's most venomous creatures as it treks south directly into the path of populated areas.

We investigate the role climate change is playing on the rising number of fatal shark attacks, before I go into total meltdown during a debilitating heat chamber experiment and finally, we’ll confront a mega bushfire, one so catastrophic it will transform the way people view climate change forever.

Darragh O’Carroll: Nowhere in the world is climate change having more of an effect than here in Australia.

The early 20th century poet Dorothea McKellar once wrote, “I love a sunburnt country, a land of sweeping plains, of ragged mountain ranges, of droughts and flooding rains.” You see, Australia has always been a land of extremes.

But today, things are getting much worse.

More than any other developed nation in the world.

Australia is rapidly changing climate is impacting the health of its own citizens and doctors around the country are sounding the alarm.

Professor Ove-Hoegh Goldberg/Biologist and Climate Scientist: Temperature of the planet is changing in a way that it hasn't changed for thousands, if not millions of years.

That's being driven by greenhouse gases which are coming from human activities mainly.

And that the prognosis for the future on our current trajectory is pretty grim.

Despite the bad news, there is a way out of this, but we've got to act decisively now.

Professor Will Steffen/Climate Change Expert: Projections I've seen show that if we don't get climate change under control, in other words, if global average temperatures go to three degrees or more, there will be large swaths of Australia which will simply be uninhabitable.

Gina McCarthy/White House National Climate Advisor I see climate change not as a planetary issue, but as a human issue, one that's impacting public   health today and that threatens to impact the very future of our kids.

Dr. Stephen Robson/Obstetrician-gynecologist: The single greatest health challenge that health care workers globally will have to face is climate change.

Darragh O’Carroll: One of the consequences of climate change is the loss of biodiversity.

Ground zero for this loss is our world to reefs, and nowhere is experiencing it faster than the Great Barrier Reef, which supports the richest, most complex natural ecosystem on the planet.

Dying coral is not just an aesthetic loss.

It also jeopardizes the discovery of future medicines and threatens the livelihood of coastal populations who rely on reefs for food and habitat.

Darragh O’Carroll: So I just arrived in Cairns here in the tropical north of Australia at the gateway to the Great Barrier Reef.

This is one of the only places in the world where lush rainforest meets coral and sustain such a high degree of biodiversity.

What a lot of people aren't realizing, though, is that climate change is affecting this area but also having tremendous consequences for human health.

Professor Rohan Davis/Biochemist About 40% of non-therapeutic drugs come from nature.

We're going to miss some major opportunities if we let climate change escalate and continue to decimate our biodiversity.

I mean, Australia is one of 17 negative worst countries in the world.

We want to protect more than just Australia.

We want to protect all of those 17 countries.

But climate change is causing some major problems there and we're losing medicines of the future.

Darragh O’Carroll: I've arranged to meet up with marine biologist Richard Fitzpatrick, who's offered to take biochemists Rohan Davis and I out on an exploratory dive on the Great Barrier Reef.

Phone rings: Good morning, Paul speaking: Darragh O’Carroll: Hey, Paul, this is Darragh, I’m with with Rich Scots.

We're heading down to you now.

We're going to Marlin Marina.

Is that correct?

Paul: That's correct.

Darragh O’Carroll: It's not long before we leave the port city of Cairns and make our way out into the vast expanse of the Coral Sea.

From the surface, everything appears is normal.

But due to recent changes in the climate, the water temperature in this part of the world has been rapidly increasing, resulting in a disastrous series of coral bleaching events.

Darragh O’Carroll: All right, Richard, these are these are your waters or where exactly we are.

Richard Fitzpatrick/Cinematographer and Marine Biologist: This is textured reef, so it's what we call a mid-shelf reef.

So, the out reef’s another hour out that way, just travel two hours to get here.

But these mid-shelf reefs are the ones that really got hammered by the coral bleaching events.

And so what you're going to see today is a recovering reef from those events.

They were a couple of years ago now, and the Barrier Reef, the actual outer barrier, you got this back lagoon area and that's where the thermal load just increased.

And there's just mass bleaching.

Darragh O’Carroll: How long does it take for that bleaching to happen and how long does it take to recover?

Richard Fitzpatrick/Cinematographer and Marine Biologist: Well, for a reef to really fully recover after a destructive event takes about 15 to 20 years.

Darragh O’Carroll: Wow.

Richard Fitzpatrick/Cinematographer and Marine Biologist: So destructive around the events on the reef you have cyclones.

Crown of thorns.

And now we have bleaching.

But destruction is part of construction.

You know, you do need corals to get reduced to rubble that can fill in the spaces for a reef to grow.

But it's that balance between growth and, and destruction at the moment with the climate change, it's all out of whack.

Darragh O’Carroll: It's too much destruction and not enough building.

Richard Fitzpatrick/Cinematographer and Marine Biologist: Yeah, and the destructive events are now too frequent.

So the corals can recover.

But if the stress from the temperature last too long, those corals will just starve and die.

But the issue that the Barrier Reef is facing is the rate of change, is too fast for natural evolutionary processes to keep up with.

It's the rate of climate change.

It's just unprecedented.

So literally the longer we wait, the worse it's going to be, because at the moment us doing nothing is kicking the can down the road for future generations.

Darragh O’Carroll: I'd heard so much about the Great Barrier Reef, the largest living structure on earth, and I was just excited to see it and experience it for myself.

With everything in order, Rohan, Richard and I set off to explore.

Music: Darragh O’Carroll: What immediately struck me was the contrast between healthy, vibrant coral and the skeletal remains of dead and bleached coral, which look more like a pile of rubbish.

If anyone has any doubts that the reef is in trouble, I'm here to tell you that the threat is serious and is very real.

To me it looks I know not a reef expert, but I saw a lot of say my health healthy coral, some not.

Richard Fitzpatrick/Cinematographer and Marine Biologist: Sounds like you're a reef expert.

That's exactly what it was.

It's a recovering reef.

There's a lot of death.

So we went over that big rubble bed, and I was pointing down going, you know, not good.

Then right at the end of it, we saw that big, beautiful candelabra of staghorn coral.

Right.

That's what that whole area would have been like if we don't have any more destructive events in another say 10 ten years, you could go in there and go, uh, it's amazing.

But what you're seeing is, is a reef in recovery.

Darragh O’Carroll: Right?

Personally, I'm like, how does that make you feel?

As somebody who's been, you know, diving these waters for how long you have.

Richard Fitzpatrick/Cinematographer and Marine Biologist: Both mixed emotions like sadness, because you can see in your mind's eye what it was, how great it would have been.

But then you see bits of hope with all these new recruits coming in and that have weathered all these storms that are hanging in there and, and they are trying to recolonize.

So it's the yin and the yang.

Right.

And I find that nearly everywhere I go now, diving on the reef.

Darragh O’Carroll: Rohan.

What do you think when you see that as that's your territory into grabbing and getting future pharmaceuticals?

Professor Rohan Davis/Biochemist I could definitely see a lot of harm destruction there and a lot of, you know, loss of biodiversity, especially on top of the coral bommie, where a lot of that that marine life was essentially dead.

But I saw snippets of, you know, optimism as well as life as we moved around the bommie, there was some sponges and cnidarians that caught my eye.

And these are two marine organisms that we know produce interesting compounds that might one day developed into medicines.

Richard Fitzpatrick/Cinematographer and Marine Biologist: It's a real race against time for you then to get this stuff in the can, isn’t it.

We've already lost a magnitude of those before they're even described.

You know, that's what's really sad is like, you know, marine biology is a relatively new science.

You know, it's only since we've been able to blow bubbles carrying these things on our back for the last 40 years, we've been sticking our heads under there and to think we lose that before we even get a chance to collect it, describe it, analyze it.

It's tragic.

Professor Rohan Davis/Biochemist: We are playing catch up and we're um, we're running out of time.

Really.

These,   these new species could be sources of medicines to the future.

Richard Fitzpatrick/Cinematographer and Marine Biologist: And much of our science has been biased in the shallow water, you know, the top 20 meters.

The stuff below that hasn't been touched at all.

We've only just had our first ever full comprehensive deep sea survey on the inside of the reef.

There's stuff down there that will never be known.

It'll be gone before, you know.

Darragh O’Carroll: So who knows what we're losing, right?

Richard Fitzpatrick/Cinematographer and Marine Biologist: Exactly where it's got to be to our detriment, right?.

Great Barrier Reef.

How well it's going to hold up as the canary in the coal mine.

It's all ecosystems, right?

But yeah, you lose the reef, you know, most of the world's populations live on the edge of the water in the tropics.

Every part of their life comes from the reef.

That goes and you've got literally billions of people will start starving.

The reef goes, erodes away, the mangroves go at heart.

More high energy storms, erosion, storms.

Darragh O’Carroll: We just I can see as a physician, that's extremely frustrating.

So I can appreciate as you guys, people ignoring the science and seeing the consequences down there.

Like that's going to be incredibly frustrating.

Yeah.

So, so what is the solution to all this?

Richard Fitzpatrick/Cinematographer and Marine Biologist: I think humanity has to be faced with absolute crises sometimes before we react.

But the crisis is happening now.

It's just hidden because it's, you know, below the water.

And that's why it's so important for the science and even the media to get the stories out.

It just to mobilize people.

But I think, you know, humanity, we're pretty smart, You know, in science and engineering.

It's not like we don't have the components out there to start fixing things.

It's just the will.

Darragh O’Carroll: Right, you don't appreciate good health until you lose it.

And so this hopefully not get to the point where we lose everything is the key to the game.

Darragh O’Carroll: Alarmed at how much destruction I saw while diving out on the reef, I wanted to speak further with Rohan Davis about the medicines we could potentially be losing in the future.

What is it about Queensland?

I know we've got rainforest right on top of the huge Great Barrier Reef.

What is it about this state that has such a wealth of potential?

Professor Rohan Davis/Biochemist: This area is just it's one of the most biodiverse regions in in Australia.

We've got so many different ecosystems and those ecosystems hold this unique biodiversity that as a natural products chemist I want to go and study and I have high hopes that in the future we're going to find new drugs from these unique locations.

Darragh O’Carroll: So how much of our new pharmaceuticals are coming from nature?

Professor Rohan Davis/Biochemist: About 40% of non-therapeutic drugs come from nature.

They're either natural products or derivatives.

There's some wonderful examples out there.

Probably most people know about morphine from the opium poppy, which has pain control, controlling properties.

Darragh O’Carroll: As a way to safeguard flora and fauna.

Rohan established a nature bank to develop medicines into the future.

So nature banks, a collection of the biota, biota, meaning plants and marine organisms that we've gone and collected over the last two decades here in the state of Queensland.

And they're set aside for future generations of scientists to work on.

So if I don't make the big discovery in the future, I hope that someone else does from these natural resources.

We've had some really interesting discoveries over the last couple of years with this nature bank collection.

Darragh O’Carroll: When climate change is threatening our biodiversity.

Are you telling me that it's threatening our potential pharmaceutical and future medicines?

Professor Rohan Davis/Biochemist: Well, and truly, yeah.

Every time we lose a species, we could be losing a potential drug or therapy of the future.

Darragh O’Carroll: So how do you personally feel that your work is being compromised by our changing climate?

Professor Rohan Davis/Biochemist: It's upsetting.

It spurs us on to to make sure we we collect these samples while we still can for future generations of scientists.

These samples, while we may not get to use them, our future scientists will and they'll make the new discoveries that are needed to treat certain human diseases in the world.

Darragh O’Carroll: Another powerful example of the threat posed by climate change in this part of the world is the Irukandji jellyfish, one of the most venomous creatures on the planet.

As the water gets warmer here in the tropical north, the Irukandji are not only appearing for longer periods, they're also pushing further south directly into the path of major cities.

It's a recipe for disaster.

Darragh O’Carroll: All right, big red warning.

These are tropical waters.

We're presence of dangerous jellyfish as possible.

Calm seas, northerly winds and high temperatures favor the presence of stingers, but other conditions do not guarantee their absence.

Persons entering these waters do so at their own risk.

I mean, this is one of the major tourist areas of northern Australia.

This is Palm Cove.

I've seen this sign and many other signs up and down this beach to find out more.

I had to visit Dr. Jamie Seymour, the world's leading expert in Irukandji jellyfish.

For a creature with such a fearsome reputation.

I was immediately surprised at just how small they are.

Dr. Jamie Seymour/Toxicologist: But that's a full grown animal.

Darragh O’Carroll: This is it.

Let's see.

They're tiny.

Dr. Jamie Seymour/Toxicologist: Yeah.

Yeah.

And that's.

I mean, that's the first thing that catches most people out.

And I mean, yes, they're on the bottom of the evolutionary tree, but these things are seriously sophisticated animals.

From a pain point of view.

It's probably up there with the world's worst venom.

Full stop.

And to give you some idea.

Zero, no pain, 10, the most you can imagine, my last trip with one of these guys I had the pain of about 40.

Darragh O’Carroll: So you were stung.

Dr. Jamie Seymour/Toxicologist: I've been down that trip 11 times.

Never, ever want to go there, ever, ever again.

It's horrific.

If someone had given me a gun at that point in time, I was in seriously debilitating pain.

It's, it's hard to get it across to people to physically be me.

But the world's worst pain.

You're getting close.

In Cairns, on average, we put 30 to 50 people in hospital a year from Irukandji stings.

That's just Cairns alone.

The problem is if you're stung, you're going to hospital.

It doesn't matter whether it's a millimeter a tentacle or 20 centimeters a tentacle.

If you're off the hospital, end of story.

Dr. Katie Chartrand/Senior Research Officer: I've had to personally warn people and they have their babies in the, you know, on the shoreline and wading in those waters.

So there's a real, real risk and threat to loss of life from that.

Dr. Jamie Seymour/Toxicologist: But the problems that you have is that we've got an idea in Cairns, but this is geographic specific.

Darragh O’Carroll: There's now a direct link between warming water and both the length of the Irukandji season and their movement further south.

Dr. Jamie Seymour/Toxicologist: What we found was the season back in 1960 was about one or two months long.

So the jellyfish would turn up in November and the last thing you got was the back end of December.

You look at it in 2000 and that season, now still starting in around about November, the seasons are dragging out to April, May, possibly June.

Though the length, increasing the season beautifully correlates with the increase in water temperature.

These animals have got all the way up and just north of Brisbane.

That's right down the east coast of Australia, who has a water got warmer, they've got further and further south.

Professor Will Steffen/Climate Change Expert: Water temperatures, particularly in the ocean, generally are rising at a much lower rate.

But up along the northern Australian coast they’re rising almost as fast as air temperatures,   they’re about one degree Celsius hotter than pre-industrial and that is what is leading to the massive bleaching of the Great Barrier Reef.

It's leading to changes in behavior of marine organisms like sharks.

It's leading to changes in the ranges of marine organisms.

Dr. Jamie Seymour/Toxicologist: If you continue to increase the water temperature and it gets warmer and warmer as we get further south, these animals will go further and further south.

Not if, but when they arrive on the major beaches down in Brisbane and places like that.

That's when all hell is going to break loose because we have no way of alleviating the problem at this moment apart from going the beaches closed, is it possible they could get all the way to Sydney if the water gets warmer?

Absolutely.

Richard Fitzpatrick/Cinematographer and Marine Biologist: You know, our lifestyle is based around the ocean and to have a danger like that move in, I think a lot of the southern Queenslanders wouldn't be able to comprehend it.

We live with it here in north Queensland.

We now have to.

But yeah, I think there'll be a long learning curve down there which will involve a lot of hospital visits.

Dr. Katie Chartrand/Senior Research Officer: We don't go out in the water without some sort of protection.

A stinger suit most of the year now, especially here along the coastline, not only those little ones, but there's some big box jellies that also can do some some serious damage.

Darragh O’Carroll: And as if to highlight the severity of the problem, while I was in Queensland, a young boy died while swimming in the coastal town of Mackay after being brushed by a box jellyfish.

You mentioned that we can fix this.

How do we fix it?

Dr. Jamie Seymour/Toxicologist: Look, I think the answer is really simple.

It's one of those problems that the more money you throw at it, the quicker you find a solution.

But we're not there yet.

We're not even close.

We still don't know how the venom operates.

And we've been working on these for probably 15 or 20 years and it's there's just so many unknowns in the whole situation.

So it's either going to be one of two things.

We're either gonna have to do something specific to remove those animals.

That's not possible, or people are gonna have to stop using the ocean.

It's going to come down somewhere.

We know climate change is out there yet.

Let's not get into an argument about who caused it or whatever.

It is there, we know it is there.

Somebody come up with a conclusion on how we fix it?

Darrah O’Carroll: One person who's trying to find solutions to the climate crisis here on the reef is Dean Miller, who heads up the Great Barrier Reef Legacy, a nonprofit organization trying to preserve coral in a living biobank.

Dean Miller/Marine Biologist: This is the holding facility of Cairns Marine, which is an industry leader really in collecting corals and fish and holding them and distributing to the world's public and private aquariums.

Right now there'd be, you know, over 10,000 coral fragments in here.

So we could effectively have in this space the entire collection of the world's coral.

Darragh O’Carroll: How big is the problem that we have?

Dean Miller/Marine Biologist: In my mind, potentially catastrophic.

Darragh O’Carroll: Right.

Dean Miller/Marine Biologist: We're losing corals at an alarming rate and we're we're losing them very, very quickly.

We've had three mass bleaching events in six years now, and over 50% of Great Barrier Reef coral, cover has already been lost.

Wait till we don't have coral reefs anymore.

Where are those billion people going to go?

What are they going to eat?

These are potentially catastrophic issues that we're going to have to face, right, I feel in the next 20, 30, 40 years.

Dean Miller/Marine Biologist: And so these are the biobank corals.

And each one of these little fragments represents a species.

So they're sitting on the little acrylic plugs.

And within that acrylic plug is a microchip.

So from the moment they come out of the water, all the data is collected on everything about the reef that they came from, the temperature, the depth, the water chemistry.

They've had millions of years to adapt to different temperatures around the world.

And we're trying to push them through that evolution process in a much faster timeframe.

So, they're struggling.

Some corals can do it, but majority are showing signs of stress.

And we need to acknowledge that this is a global problem now.

Other reef systems are completely collapsed.

Dean Miller/Marine Biologist: We're in a unique position in that this is an opportunity to bank the biodiversity of corals now, whereas in other places of the world it's either happening right now or it's too late.

Darragh O’Carroll: As I was speaking with Professor Rohan Davis, he was saying that we're losing biodiversity and his ability to find different chemicals that can be applicable for medicines that I could be using in the emergency department.

We're losing.

Dean Miller/Marine Biologist: Absolutely.

So it's really an untapped resource.

And when you think that there's 800 to 1,000 coral species around the world that we really know very little about in terms of their genetic, I guess, bio prospecting potential.

So one of the things this project does is collect a living sample.

Then we run the genetics and we'll have the full genetic sequence for each one of these coral fragments.

And someone like a pharmaceutical or medical research lab will have access to that full genetic information.

Darragh O’Carroll: So this could be the cure to prostate cancer, or this one could be the one that fights COVID or something like that.

We just don't know what's out there yet.

Dean Miller/Marine Biologist: We don't know what's out there.

Darragh O’Carroll: What gives you hope for the future?

Dean Miller/Marine Biologist: The biggest hope is that we can do something right now.

Collecting the corals and keeping them alive in a biobank-type scenario allows us to at least maintain that biodiversity.

But there's lots of other stuff we need to be doing.

So that's one piece of the puzzle.

Really needs to address climate change head on.

And I think as a global community, unless we start to make radical changes, we're going to lose the race at the end of the day.

And I feel like people will do the right thing at the end of day.

Darragh O’Carroll: A warming planet not only threatens the health of coral, it's also causing extreme drought and oppressive heat the world over.

In fact, heat waves kill more people across the world than any other weather phenomena.

In Australia alone, an average of over 500 Australians die of heat illness every year.

Professor Will Steffen/Climate Change Expert: So I would say that extreme heat probably is the number one factor that's driving change in our climate and driving health, health impacts.

Gina McCarthy/White House National Climate Advisor One of the biggest and most immediate challenges across the world is heat stress.

Basically, as the weather gets more extreme and hotter, we are anticipating many more 100 plus degrees in the United States, specifically in the Southeast.

Darragh O’Carroll: To learn more about the problem, I travel to Sydney to visit Professor Olly Jay, a leading heat and health expert at the University of Sydney.

Professor Olly Jay/Professor of Heath and Health: We're facing pretty dire consequences potentially in certain parts of the world, particularly areas of northern India, for example.

They already experience very high temperatures alongside quite high humidities as well.

Here in Australia, of course, we might expect temperatures to increase quite substantially as well.

There’s also the humidity that's associated with that.

Professor Ove-Hoegh Goldberg/Biologist and Climate Scientist: For a long time, people, we're not really taking the health impacts, which with the seriousness that the expert community was talking about.

They were talking about the fact that we could get to temperatures where it's impossible to live outside without an air conditioner.

This is when, you know, things are so humid and so hot that you literally can't keep yourself cool and you die.

Gina McCarthy/White House National Climate Advisor And so we can expect that heat stress will, will continue to cost thousands of lives every year.

For some reason, people aren't embracing that threat as much as they should.

Darragh O’Carroll: To get a taste of heat stress in a simulated environment.

Dr. Jay invited me to exercise in a heat chamber, something I must say I wasn't looking forward to.

And if that wasn't bad enough, I had to swallow a thermometer pills so they could measure my core body temperature.

Professor Olly Jay/Professor of Heath and Health: What we see at the moment is that heat waves, we definitely get heat waves with 45 degrees Celsius or even warmer.

But the challenge in this particular case will be the higher humidity.

So when you're indoors, it's pretty difficult to simulate an outdoor environment.

You can simulate the temperature and you can simulate the humidity.

But what we can do with this facility as well as up to an extent, we can simulate the extra thermal radiation that comes from being in an outdoor sunny environment, so.

Lab attendant: It's very what it's doing is is monitoring what your breathing in and what you're breathing out.

Indinstinguishable discussion as experiment starts: Darragh O’Carroll: Growing up in Hawaiʻi, I was used to working and exercising in tropical heat, but nothing could have prepared me for this.

The future is hot, very hot.

I am alright for now, you see this sweat is dripping off me.

I'll do that at the moment.

I can feel myself heating up.

My core temp is up point one degree Celsius but my heart rate, 30 over 141.

So my body is feeling the effects.

Darragh O’Carroll: Fifteen minutes into the exercise and I was in a pool of sweat and I was so hot I felt my head was about to explode.

The future is definitely really hot.

I mean, I wasn't even doing much work.

You guys saw me like a slow jog and I felt like I was sort of suffocating and I'm not an unfit guy, you know, that's not possible to live with in the future.

I mean, that was only 20 minutes or less, some around 20 minutes for some reason that all day I mean, you're talking about chronic dehydration or even heat stroke or heat exhaustion before 3 hours are done.

I hope it's not what's coming because that's not bearable.

Darragh O’Carroll: It's hard to imagine how people can function and work in such debilitating conditions.

And it just gave me a small insight into what life could be like in a warmer future.

Professor Olly Jay/Professor of Heath and Health: So once we surpassed the age of 65 or 70 years old, you start getting age-related reductions in the ability to sweat.

So the other group of people that we're also concerned about are people who are physically active.

So if because of your job or because of the sport that you participate in or something like that, so in that situation, you’d be more likely to experience something called exertional heat stroke.

Whereas the other situation, I would describe older individuals who just simply at home can't keep cool.

That would be something called classic heat stroke.

Darragh O’Carroll: Heat stress, I can now feel it now personally that it's the number one killer going forward when it comes to climate change.

More people are going to die of heat, stress than everything else.

Gina McCarthy/White House National Climate Advisor Every year, thousands of people die as a result of heat stress.

This is not a unique to the developing world.

It's in the developed world as well.

Professor Will Steffen/Climate Change Expert: At the end of the day, we've got to be making sure that we turn that, those greenhouse gases off, because if you don't turn them off, then all of this unique and innovative science will be for nothing.

Darragh O’Carroll: Rising temperatures are not only affecting the health of humans, they're also affecting shark behavior.

In the last few years, the east coast of Australia has experienced an unusually high number of fatal shark attacks.

To find out more about the problem, I caught up with leading shark researcher Dr. Daryl McPhee on North Stradbroke Island, the scene of a horrific, fatal attack.

So Daryl, what makes this area prone to shark attacks and having to have that sign up there?

Dr. Daryl McPhee/Environmental Scientist: The environmental conditions here are perfect for bull sharks in particular.

We have an extremely deep channel riding close to the beach and we have all the water coming in and out of the bay in a large, large environment which sits next to Brisbane.

And most of the fish that come in and out, lots of schooling fish like sea mullet, which are really preferred food in this area for bull sharks are hugging the beach and the sharks can follow.

Darragh O’Carroll: Back in 2006, in this very spot, a 21-year-old girl suffered a terrifying fatal attack when she was mauled just meters away from the beach by a number of sharks.

And it's an encounter that still haunts this area today.

Dr. Daryl McPhee/Environmental Scientist: What was so bad about that shark attack was was that it occurred in the late afternoon, quite a hot day when there was a lot of families here… was multiple bites from multiple bull sharks.

And it really just shattered the community.

And that shark bite is still etched indelibly on people's memories.

Darragh O’Carroll: Daryl, there's been a recent record number of fatal great white shark attacks here on the East coast of Australia.

What's the role climate change may be having?

Dr. Daryl McPhee/Environmental Scientist: There's never one reason for a trend in unprovoked shark bites, but certainly on the Australian east coast, with changing currents and warming water, there's a correlation between those factors and the occurrence of sharks on beaches where people are swimming and surfing.

What's been unusual, particularly the last couple of years, is a high number of fatalities.

Darragh O’Carroll: In 2020, the east coast of Australia experienced 22 unprovoked shark attacks, including eight fatalities, making it the worst year on record.

Dr. Blake Chapman/Marine Biologist: If we're seeing an influx of sharks or really high numbers, lots of sightings of sharks in one area, we have to kind of wonder what's bringing them in there.

Are they following prey or is there something in the environment that's telling them this is where they should be?

So when we were talking about what could be changing shark movement, shark behavior, we have to look at those environmental cues.

Richard Fitzpatrick/Cinematographer-Marine Biologist: The sharks are moving around in relation to food and where their food goes is where they go.

And so, what we find with climate change is that their prey is being affected.

So therefore, ultimately sharks are being affected.

We know that their migratory patterns are getting pushed by climate change as well.

Warming seas are changing where and where those currents occur.

Dave Pearson/Shark Attack Survivor: We all have theories as to why we see more sharks now.

And I've had a dozen encounters in the last 10 years at least.

Darragh O’Carroll: Do you foresee more attacks due to the changing climate and the changing ecology of the ocean?

Dr. Daryl McPhee/Environmental Scientist: Again, it's very difficult to predict, but I certainly wouldn't be surprised.

With increasing warmer water, you actually expect to see more bull sharks spending longer in the greater Sydney region and even pushing further south.

The other climate change trigger was bull sharks respond and move to beaches during rain, particularly flooding rain.

So the more flooding rain you get, the more overlap you expect with bull sharks with surface.

Richard Fitzpatrick/Cinematographer-Marine Biologist: The seasons are going longer.

That means people will be spending more and more time in the water.

So therefore, the chance of a negative shark, human interaction also increases.

Dr. Daryl McPhee/Environmental Scientist: Australia's population is going to continue to increase.

A lot of people are going to go to the beaches just to try and cool off.

More people in the water equals the potential for more shark bites.

Darragh O’Carroll: Incredibly, just a day prior to meeting with Dr. McPhee, my producer shocked me with the news of another fatal shark attack of this time in Sydney and the first in 60 years.

Producer: Darragh, you are not going to believe this.

Fatal shark attack in Sydney (unintelligible), dies for first time in 60 years.

Darragh O’Carroll: Mauled to death by a man eaters, great white.

Producer: It was a great white.

Second producer:  There is a video.

Someone caught it on film too.

(unintelligible) Darragh O’Carroll: Having worked in the E.R.

I've seen all sorts of trauma, but nothing could have prepared me for the horrific scenes as a five meter great white mauled a swimmer.

So I've just seen a really horrific video of a fatal shark attack in Sydney.

It's all over the newspapers as well.

What's your take on that.

Dr. Daryl McPhee/Environmental Scientist: Absolutely horrific video?

It really puts things in a context that was clearly a shark intent on killing that particular person.

Dr. Blake Chapman/Marine Biologist: It was a very sustained attack.

And it just continued.

So there was obviously motivation there.

We don't tend to see that predatory motivation that often from great white sharks.

In every sense of it.

It was an absolutely horrific example of what can happen.

Dave Pearson/Shark Attack Survivor: I guess the whole world got to see the brutality of a shark attack.

That's I know that I don't need to see that to know that.

Darragh O’Carroll: Having survived a brutal attack himself while out surfing, Dave Pearson understands the problem as well as anyone.

Dave Pearson/Shark Attack Survivor: We got down the beach and just the beach that we always surf at.

When I was paddling out after the third wave, then just bang.

It was just totally not expected.

It hit me like a freight train and it's bottom jaw got stuck in my surfboard on the way through.

All I remember was tons of bubbles and then something big in front of me.

I was semi-conscious, like I was so dazed.

I was looking down on my arm and all of these muscles was just hanging over and the blood was squirting probably 6 to 8 foot from where I was sitting.

I tacked back over squeezed as hard as I could to just try and stem it and as I’m squeezing it, it’s squirting through my fingers and I'm thinking, well, this isn't that good at all.

Just as I was looking in the water, I seen the shark directly under me.

It was still probably only two foot under the water and it was like, you know, five foot that way and five foot that way.

It was big fish and I went, (bleep), I'm going to die today.

I was in a ton of pain, but if you're in pain, you're alive and I was pretty happy about that.

Darragh O’Carroll: Alarmed at the rising number of attacks and the lack of post-traumatic support, Dave Pearson founded a support group called the Bite Club.

Dave Pearson/Shark Attack Survivor: The first year out of, you know, after a year attack, it's a mental mess that you don't need to get into.

I searched to see if there was any support network and slowly I got in touch with a few people and it was really nice to be able to help people through some really tough times.

And and they've helped me just as much.

Darragh O’Carroll: Most of the climate predictions I've been hearing are that waters are just going to continue to get warmer and warmer and warmer, so, how problematic can this be for surfers and people who are in the ocean?

Dr. Daryl McPhee/Environmental Scientist: Potentially extremely problematic.

We do know that in amongst the information on unprovoked shark bite, there is a climate change signal in that there are some correlations at times concentrating some white sharks closer to that shoreline and overlapping more with people.

We’ll expect to see bites in Australia from bull sharks and tiger sharks to extend further south.

And likewise, in the US mainland, we expect to see bull sharks and tiger shark bites moving further north.

Dr. Blake Chapman/Marine Biologist: As the water gets warmer, sharks are going to be moving.

We're already seeing that distribution is changing.

We're seeing it in bull sharks.

We're seeing in tiger sharks in Australia and in other places around the world.

So we will have to understand that these sharks are going to be popping up in places that we haven't seen them before.

Dave Pearson/Shark Attack Survivor: The difference from when I was younger to now, it wasn't as many attacks, that's for sure.

But now there's a lot more awareness about what's out there.

And we should be shark smart, We should be smarter about what we do and not put ourselves in a situation could lead to us being attacked.

Dr. Blake Chapman/Marine Biologist: To ask humans to change their behavior is a big ask.

But I think that what people just need to to do is to be aware, to educate themselves, to know the risk and to do whatever they can to mitigate against that risk.

Richard Fitzpatrick/Cinematographer-Marine Biologist: We want to alter an entire ecosystem by culling sharks, removing sharks.

So then we have a safer environment for recreation.

It's kind of a bit the height of human arrogance, I think, for us to think that oh let's change a whole ecosystem for our pleasure.

Dr. Daryl McPhee/Environmental Scientist: So for that extra peace of mind and in fact extra risk reduction, there are scientifically tested shark deterrents that do actually work, but none of them are 100% effective.

The risk of a   shark bite is low.

It will remain low, but it will never be zero.

Darragh O’Carroll: So I’m now heading south down to Canberra to see Professor Will Steffen.

He's an expert in climate science.

It's amazing that just two years ago Australia had its worst bushfire season on record and now we're driving through what allegedly is a one in 1,000 year flood.

Emergency broadcasts: Evacuation warnings have also been issued (unintelligible) flash flooding   (unintelligible) if you are traveling around anywhere in the metropolitan area.

Darragh O’Carroll: This really is a land of climate extremes.

Professor Will Steffen/Climate Change Expert: So climate change is basically a disruption of the energy balance at the surface of the earth.

We are changing the energy balance of the lower atmosphere and of course it changes circulation, changes how rainfall and where rainfall falls, it changes extreme weather events and all sorts of things like that.

Darragh O’Carroll: What are the general climate trends that are happening here in Australia?

Professor Will Steffen/Climate Change Expert: Well, probably the first and foremost one is it's getting hot, really hot.

So extreme heat is going up.

That's still the number one killer of climate related extreme event.

And it's affecting all of our capital cities.

It's affecting the bush, affecting everything.

So it's this combination of our coasts are changing.

We're heating, we’re burning more.

When droughts come, they are much more severe.

They tend to be longer and they tend to be drier.

It's spreading around the rest of the world, too.

But I think there's nowhere like Australia where climate change now is so pervasive in so many different ways and to such extreme.

All the natural variability we have is getting worse.

When storms come, their packing more power, when rain comes, it rains more, more runoff, higher flooding, sea levels are coming up, storm surges are coming in.

The other thing I think that makes Australia so unique is we've put a lot of our people and infrastructure in vulnerable places.

We love our coastlines.

So all of Australia's major cities except the one we're in now, Canberra, all the others are located on the coast.

People love to go down to the beach, up to the houses on the coast, but sea level is coming up.

Storm surges are becoming stronger.

So we have a lot of infrastructure, a lot of people at risk from rising sea levels.

Professor Will Steffen/Climate Change Expert: So it's a combination of a very erratic climate and just sort of by the way we live, we've tended to put ourselves in harm's way.

Darragh O’Carroll: As the water continues to warm, Professor Steffen also has real concerns for the health of the Great Barrier Reef.

Professor Will Steffen/Climate Change Expert: Coral reefs are really, really in a very vulnerable position now, and I think my prognosis is that not many of them are going to survive.

Remember also that the oceans absorb 90% of the extra heat that we're generating with greenhouse gases.

Big ocean currents are going to start to change, speeding up, slowing or whatever.

That's going to wreak havoc with climate around the world.

A lot of other continents, they haven't experienced it like we're experiencing it, but it's going to come.

Darragh O’Carroll: Are we in a climate emergency?

Professor Will Steffen/Climate Change Expert: Absolutely.

We're in a climate emergency.

Temperatures are accelerating.

Our emissions are increasing.

So not only do we have to reduce them, we've got to learn how slow them down really fast, peak them and get them going now.

Darragh O’Carroll: People don't appreciate their health until it's gone.

How do you personally feel about the inaction that may be happening.

Professor Will Steffen/Climate Change Expert: For many people, climate change was theoretical.

It was a science problem.

Something for the future.

Exactly.

As you say, it's only after you lose something that you realize how much you valued it, like your health, obviously.

And then when I tell them that these major events don't just change linearly as an even group, they go up sharply.

And so 1.5, it's going to be much more than 50% worse than one and two degrees is going to be far worse than double what's happening at one.

And then I reminded just remember the last couple of years what was happening at one degree.

We still have a fighting chance, but we've got to move fast.

Darragh O’Caroll: Despite all the negativity, Professor Steffen hasn't given up all hope just yet and is encouraged by the attitude of the world's youth.

Professor Will Steffen/Climate Change Expert: We see all sorts of what I call trusted voices now standing up.

It's hard for people to forget about what the young people are saying, saying it's our future.

You, older people are in charge of making sure we have a livable future and you're failing us.

That's a strong message.

But medical people are speaking out like yourself.

Firies are speaking out.

Farmers speaking out.

Sportspeople are speaking out.

So this idea that we need to move and we need to move past is permeating many aspects of our society.

And it's not unique to Australia.

It's happening in other parts of the world too.

Can we get to the social tipping point in time?

I don't have the answer, but every day when I see someone else speaking out, it gives me some hope that we might get there.

Darragh O’Carroll: Greg Mullins The son of a fireman and a fireman himself with over 50 years of experience fighting fires on the front line, was so alarmed by climate change and its effects on bushfire, he felt compelled to write a book called Firestorm.

Greg Mullins/Former Fire Commissioner: When I first became a firefighter, nobody was talking about climate change.

It wasn't even on the radar.

And my father taught me about the fire seasons and patterns of weather.

What I'm seeing across the world is climate change is driving up temperatures, it's drying out forests, even wet rainforests never used to burn for millions of years, couldn't burn.

Now they're burning.

So this problem is getting bigger and bigger and bigger.

Speaker: Wildfires get turned on by particular types of conditions.

It's the increase in those conditions, the dryness, the amount of tinder, the temperature that are driving this sort of cycle of fires.

Darragh O’Carroll: In the summer of 2019-2020, climate change came to a head in Australia when the east coast of the country literally went up in flames.

It was a fire so intense, so catastrophic and so widespread it would change Australia's view on climate change forever.

It was a fire so devastating it would make the whole world stand up and take notice.

Stretching right along the east coast of Australia and burning for over six months, the fire would become known as Black Summer.

Professor Will Steffen/Climate Change Expert: So, if you look up the Australian east coast from Victoria up through to southern and central Queensland, on average about two or 3% of those forests burn every year.

That is a normal bushfire summer.

We’re equipped to handle it.

Firefighters could go out and deal with a wildlife can deal with it.

That's the way ecology works.

When 2019 and 2020 came along, we jumped from two or three or 4% to 21% burnt in one year.

Greg Mullins/Former Fire Commissioner: We had our hottest, driest year ever recorded in Australia, so it was far more severe than any previous drought.

So they're saying it was the worst drought on record.

Speaker: The forest became critically dry and the temperatures became critically hot at the same time.

So it crossed the threshold in which the fires were uncontrollable.

Andrew Flakelar/Volunteer Firefighter: There was so much fire activity going on over such a large area from the top of the state all the way down into Victoria over such an extended period of time.

It was months and months, consistent devastation, consistent destruction on a scale that we hadn't seen ever before.

Peter McKechnie/NSW Deputy Fire Commissioner: Not just the sheer scale of them, but the length of time they went for.

Rather than fighting fires over two or three months, we were fighting fires in some areas from August right through to the end of February into March.

Greg Mullins/Former Fire Commissioner: I saw kangaroos on fire, dying on fire, coming out of blazing forests and they know how to get away.

They know where the water is and they’re fast the, the fires out ran them.

Andrew Flakelar/Volunteer Firefighter: What I heard was so loud that I turned around and was confronted with a wall of flame unlike I'd ever seen this enormous explosion of power.

And it was it was deafening.

Professor Will Steffen/Climate Change Expert: People were trapped and had to make for the sea.

Were standing on the beaches as fires were bearing down, the Navy had to come in, bring them out.

Greg Mullins/Former Fire Commissioner: We had a pyro convective storm above us, which used to be something of legend.

You know, all my time fighting fires.

I've never seen that now so common during that fire season.

There was one instance during the fires where an eight ton fire truck was picked up and dumped on its rig and killed one firefighter.

Professor Will Steffen/Climate Change Expert: I can show you an image of flames that are 50, 60 meters high within sight of Canberra.

We were within hours of having 450,000 people trapped.

I don't know how many people realized the situation, but I was really sweating that night.

Andrew Flakelar/Volunteer Firefighter: In the time I've been in the fire service, I've seen some really significant fires,   never to the scale of the amount of fires and five and a half million hectares that were burnt here in New South Wales by far and away exceeds what we've ever dealt with before.

Greg Mullins/Former Fire Commissioner: No firefighting organization on this planet could have dealt with those fires.

Professor Ove-Hoegh Goldberg/Biologist and Climate Scientist: We're now talking about mega-fires, things that are going for for longer, hotter, more intense, more threatening and so on.

We're seeing these things start to amplify.

Greg Mullins/Former Fire Commissioner: We lost 2,476 homes, 11 times more than any previous fires in history in this state.

Professor Will Steffen/Climate Change Expert: Fires are now appearing in ecosystems and regions of Australia that they hadn't before.

So in addition to the intensity of huge fires in the eucalypts, other force which didn't burn are starting to burn.

Why?

Because they're having extended dry periods and then heat.

Greg Mullins/Former Fire Commissioner: There's big parts of this state where there's nothing there you go there,   there's not even birds.

It's sterilized because for hundreds of kilometers it's just blackened and everything died.

So our scientists are saying there's never been anything like this or as widespread as this or as intense as this.

And so a firefighter who's been on the front lines for 15 years, I've never seen anything like it.

Professor Will Steffen/Climate Change Expert: There's now very strong evidence that they wouldn't have occurred without climate change.

Well, as you know, as I mentioned, we're a fire prone continent anyway.

But normally that would be maybe three or 4% of the forests burned.

And you went back three decades and you saw this oscillation and then you saw over the last decade, it kept creeping up, up and up and up.

And by the time 2019 came by, it was probably at the 99th percentile.

In other words, above anything else in terms of the combination of drought and heat.

Andrew Flakelar/Volunteer Firefighter: It's easy to say, well, we've had fires before.

I definitely consider the fact that major fire events are inevitable, but the climate change is making it so much worse.

We haven't seen it on this scale before and this is why we should be paying more attention to it.

Professor Will Steffen/Climate Change Expert: Climate change just shoved the temperature that much too high.

The drought was that much to try and the whole thing took off.

Darragh O’Carroll: Bushfires not only threaten ecosystems and whole communities, they also have a devastating effect on human health.

Greg Mullins/Former Fire Commissioner: During our fires, 33 people were killed, including nine firefighters.

I was actually astounded because I thought there'd be a thousand, but 450 people died from the effects of smoke.

So major capital cities of Sydney, Melbourne and Canberra were just covered in smoke.

Peter McKechnie/NSW Deputy Fire Commissioner: I understand there was some studies done that showed once that got it up into the upper atmosphere, that smoke was actually circling the planet.

We saw heavy, heavy effects of smoke impacting human health for months on end.

So it was very much not only that immediate effect of how far the smoke would go, but the cumulative effect as well.

Dr. Stephen Robson/Obstetrician-Gynecologist: One night I was delivering a baby when there was this spotlight and it was just running through smoke, and we realized that the whole birth room was full of stink, acrid, bushfire smoke.

Dr. Kerrie Aust/General Practitioner: As people start to inhale more smoke.

And we saw massive increases in hospitalizations.

Dr. Stephen Robson/Obstetrician-Gynecologist: During the bushfires I delivered babies who ended up in a nursery at rates that I had not experienced before.

Darragh O’Carroll: Our health is being impacted across the globe yet there doesn't seem to be the action that's needed yet.

Dr. Stephen Robson/Obstetrician-Gynecologist: It's impossible for the world to function if people aren’t healthy.

There is no theoretical future threat to people that people are living in now.

We are seeing heatwaves, we see bushfire smoke affecting people and people are very anxious about their children's health.

So it's really been an extraordinary change in philosophy.

Darragh O’Carroll:  Was Black Summer a warning for the rest of the world?

Greg Mullins/Former Fire Commissioner: Most definitely.

And soon after that California burned yet again and tied together.

So there were big warnings and no human being has fought fires in those conditions before.

We're heading for 2.7 degrees, which is catastrophic for the human race.

Darragh O’Carroll: Indigenous Australians have been successfully managing the environment with controlled burns for thousands of years and it's a practice that the Western world can learn from.

Greg Mullins/Former Fire Commissioner: Europeans have been here for about 200 years and for 60,000 years before that, the indigenous people managed the land and healed the land and we've screwed it up in just 200 years.

Darragh O’Carroll: So what can the indigenous of this land teach us about fires?

Robert Lafragua (Yunganda)/Mossman Gorge Tour Guide: Well, I believe there's a lot of buildup of fuel and that's creating a lot of fires.

Once that fire goes, it's pretty hard to sort out if you've got a lot of fuel around.

Peter McKechnie/NSW Deputy Fire Commissioner: The cultural burning really does have a place.

The more we can look at how it integrates into our fire management practices, now, I think we’ll all win from that.

Robert Lafragua (Yunganda)/Mossman Gorge Tour Guide: Bushires can be reduced If we do a lot of traditional burning.

We just don't go walking in and burning the whole area.

We burn certain areas, section by section so we don't create a big mega bushfire.

Peter McKechnie/NSW Deputy Fire Commissioner: Cultural burning has much deeper meaning than it just being as simple as saying it's a good way to do hazard reduction.

Why is it required?

What is the connection to country?

Darragh O’Carroll: Climate change is having such an impact on the severity of fires in Australia.

It's forced the authorities to extend the fire danger rating from extreme to catastrophic.

Greg Mullins/Former Fire Commissioner: It's an algorithm that takes maximum temperature, lowest relative humidity, the moisture in the air, highest wind speed and a drought factor number of days since rain jumps it all up and comes up with a number between one and 100.

The Fire Authorities council decided together with the federal government, we need a new category.

Once it gets to catastrophic leave the day before.

Professor Will Steffen/Climate Change Expert: I think more than any single incident, that is the one that's got people realizing that climate change is not only real, it's not something for the future.

Andrew Flakelar/Volunteer Firefighter: We continue to learn more and hopefully we can implement those learnings to better mitigate the risks.

Peter McKechnie/NSW Deputy Fire Commissioner: So we now know what the new worst is and we need to be getting ready to deal with that or worse.

Dr. Stephen Robson/Obstetrician-Gynecologist: The thing that gives me hope for the future is children are utterly focused on the health of the planet in a way that never happened when I was a kid.

They want ethical and responsible environmental stewardship.

I see that fundamental to the way the watch work.

Dr. Kerrie Aust/General Practitioner: Watching my kids fire up about climate change is really exciting.

This generation cares a lot about the climate.

Richard Fitzpatrick/Cinematographer-Marine Biologist: It is quite an exciting time, especially for kids coming through now because the answers will   be science and technology.

Everything's been looked at.

Nothing's off the table.

Professor Will Steffen/Climate Change Expert: Climate change.

It's not something for the future.

This continent is probably the most vulnerable, and we're feeling that right now.

Professor Ove-Hoegh Goldberg/Biologist and Climate Scientist: There is a huge capacity for us to solve problems.

If we consider them to be problems worth solving.

We need to make sure that people realize that this is a problem worth solving because it's the planet upon which we live on and there is no other planet.

Gina McCarthy/White House National Climate Advisor But we have a moral responsibility to take care of those most vulnerable and to hand our kids a future that we want to be proud of.

Greg Mullins/Former Fire Commissioner: Treat it as an emergency and go on a wartime-like footing to turn this around.

Dr. Stephen Robson/Obstetrician-Gynecologist: Anyone who is involved in delivering babies and delivering a new generation has an interest in making sure the babies we deliver, their children have the healthiest possible starting lives.

Professor Ove-Hoegh Goldberg/Biologist and Climate Scientist: We must get on with the solutions if only for the kids.

I mean, you think about children and what we're leaving them.

That's the great moral argument.

Darragh O’Carroll: Do you think as physicians, we should be leading the charge in the climate emergency?

Dr. Stephen Robson/Obstetrician-Gynecologist: It is our absolute responsibility to make sure that we are in the lead.

Both in advocacy and in how we live our own lives and how we treat our patients.

Dr. Kerrie Aust/General Practitioner: We need people power.

Humans need to take responsibility, and it'll come back in terms of the health benefits for us.

Professor Will Steffen/Climate Change Expert: Because it's not all over.

But it is one of those grand challenges that we must meet and we are staying away from the solutions is not an option.

Darragh O’Carroll: I've learned a lot about climate change in my time down under and how it's affecting health in ways I never thought possible.

I've also seen that now more than ever, I'm hopeful we will act because when it's our health, we can't afford to wait.