Climate Change

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You know all that stuff that we can't fit in?

Yeah, what you mean into the general recording when it goes out on radio four?

Yeah.

Well, I think we should put it in something else.

Well, I've made that already, and they can listen to it now.

Don't know why you've been dragging this down.

Oh, the Infinite Monkey Cage podcast.

Now.

It's now.

They're hearing it now.

Well, not now, because I'm still saying now.

When I stop saying now, they'll hear it.

I I think

simultaneity is a big question in relativity.

I don't think there is such a

universal now, so I don't think you should say that.

Would you wonder why we can't fit everything into the recording?

It's ridiculous.

Hello, I'm Robin Enitz, and I'm Brian Cox.

And welcome to the last episode of this series.

We can only do six because, of course, Brian has to be taken away and rebooted and remodeled every five weeks.

What, you thought he was human?

Look at that face.

That is not a human face.

There are some scientific subjects that people just can't be bothered to talk about.

There are some scientific subjects that people can't talk about because they've just never heard of them and know nothing about.

Here's what I think, Nigel.

One of those.

I have never seen you do Cockney before and it is fascinating.

I don't know why I'm not sure if I can do it.

It's like the revenge of every northerner who said, well, we don't sound like that.

Anyway, there are a few subjects though, which some people know everything about and they know the utter truth and they are utterly certain about it.

And that is the one that we're dealing with tonight because tonight we are dealing with climate change.

What is the climate?

Is it changing?

Is it our fault?

And is there anything we can do about it?

And should we do anything about it?

Isn't it about time we just allowed the giant dragonflies to finally rule the world again as we go smiling towards oblivion?

So, our panel tonight is.

Hello, I'm Dr.

Gabrielle Walker.

I've been a scientist, a broadcaster, a writer.

I've written four books on how the climate works, and I'm chief scientist of Zinteo, a company that works with businesses to help make them fit for the future.

And my hope for humanity in the next next hundred years is that we collectively manage to avoid putting ourselves as a species out of business.

People don't normally get applause after that.

That was a very popular choice,

going against the idea of human extinction.

They're enjoying that one, which is unusual for Radio 4 and very unusual for Jeremy Vine's audience.

Hi, I'm Tony Ryan.

I'm the Pro Vice-Chancellor for the Faculty of Science at the University of Sheffield Sheffield and Director of the Grantham Centre for Sustainable Futures.

Now, my hope for humanity in the next hundred years is that we reduce the carbon dioxide level to three hundred parts per million and reach a balance of carbon emissions and thermal emissions so that the Earth's surface stays at the same temperature for a long time so we can stay in business.

Now,

on the clapometer, not as popular as the more general lack of human extinction.

But let's see how our final contestant guest will do.

Hello, I'm Darbreen, a graduate of University College Dublin, the Dean of the School of Neuroscience at Oxford.

Lion Aye Prattler, Fellow for the universities in Cambridge and surrounding areas.

And my earnest hope for humanity over the next 100 years is that we stop producing DVDs, novels, box sets and video games so I can catch up.

Let's start off with you, Gabriel, and just ask, we'll get a few definitions first.

When we say climate, what do people mean by climate?

What's that term mean?

Oh, it's a nice question because actually, people think about climate, they often think about weather.

And weather's something that happens every sort of day, every few minutes, every hour, something that changes all the time.

And climate's kind of like the average of weather.

It's almost the probability of how likely some weather's going to happen.

So climate's really over kind of years, decades, and weather's over minutes, seconds, days.

And Tony, now we've got definitely.

So, what is the evidence?

Why do we believe it is changing at unexpected rates, shall we say?

Evidence.

So, many, many

years of measurements, initially by people recording the temperature locally, writing it down,

instrumental records from surface stations all over the world, then balloons, global satellite data.

There are many surface, sea surface temperature and depth measurements because a lot of the heat's stored in the oceans.

So there's a phenomenal amount of data, all of which has been put together over

300 years of measurement.

And then there are many ways of getting further back.

Isotope ratios in ice cores, in calcite deposits.

So there's data.

Data, data, data.

So when you say isotope ratios, obviously I have a keen understanding of exactly what you mean, but some of our audience have been paying less attention.

What do you mean when you say isotope ratios?

An isotope, Robin, is an atom

of a particular element with a different number of neutrons in it.

Heavy, heavy.

I was thinking about others, Brian.

I'm sacrificing myself and creating the illusion of stupidity.

Very good on Beowulf and Dombey and some.

But to get back to why the isotope ratio changes, my favourite bit is how the isotope ratio changes.

In Beowulf.

In Beowulf.

Have you not seen it?

It's a footnote.

You need to read the footnotes.

So you can get heavier and lighter versions of oxygen, and the balance of the two of them tells you what temperature the ice or snow was when it first formed.

But you can also, this is really cool, and the ice cores themselves, there are little bits of air that are trapped.

I've actually seen one melted.

I've been where they drill it and smelled it.

And it can be as old as 800,000 years.

So, this air was first trapped in the ice before humans were even invented.

You can go all that way back and for 800,000 years, layer after layer.

You can smell it, you can test it, you can see what's inside it, and you can see how much carbon dioxide there is, and you can see what the temperature was when it was formed.

So, so we have an accurate record or a reasonably accurate record of climate stretching back, as you said, many hundreds of thousands of years.

Pieces of air, real pieces of air, not something that's interpreted, but that you can actually see.

So, what's the evidence that suggests that

leads us to worry about the rate of change of climate over the last century, let's say?

And what's the evidence that we are the cause of it rather than something else?

So, there's two things to worry us about the pace of change.

One of them is that if you look at the way that

naturally carbon dioxide, other greenhouse gases, they go up, they go down, and temperature just goes up and goes down in different times very naturally.

And the two go in lockstep: when the temperature is higher, the CO2 is higher, when the temperature is lower, the CO2 is lower.

You know that there's a strong connection between them by looking in the ice cores, right?

So, the first thing is we know they're connected.

And what's happened very recently is this incredibly rapid and very sudden rise in carbon dioxide, and an incredibly rapid and very sudden rise in temperature, much faster than you see in the record.

But there's another thing to worry about: the pace of the change, which is we also know that the climate system in itself can make sudden changes.

And if you kick it, if you kick it hard enough, enough, it can change into something else.

So we know that the change is happening faster than it's ever happened before in that record, that 800,000 years.

And we also know that if you kick the climate system, it can really move.

So

we're worried about some unpredictability in our understanding.

Yeah.

Well, there are always oscillations, but it's the rate that's the issue, the rate of change that

makes people, what makes us worried, because we can't predict what that rate of change will produce in a climate.

I think you also asked, Brian, why we know that humans have caused this.

So, we do know that carbon dioxide changes very naturally.

And we also know, though, that we've been burning a lot of fossil fuels, we've been burning down trees, and those are the two things that produce greenhouse gases in the atmosphere.

Also, doing agriculture and using fertilizers produces nitrous oxide, so nitrous oxide, carbon dioxide from burning things, and methane is another greenhouse gas as well that we've been pulling out of the ground.

And when you put those three things together, you can see in the ice core record how much methane and carbon dioxide and nitrous oxide there used to be.

And then you can look back 800,000 years and see in that period how much has it changed.

And then you can look at the recent times and see how it's gone through the roof.

And you can also calculate how much there ought to be there if you look at how much we've burned.

And in fact, they match.

A lot of it's actually gone into the ocean, but a lot's also gone into the atmosphere.

And then the final part of it is if you try to look for everything else that's going to cause the recent warming, we know it's warming, there's no doubt about it, we know it's warming.

You look at everything else that could have caused it, changes in the sun, sometimes the sun gets a bit hotter or colder, or changes in volcanoes.

Sometimes volcanoes put out particles that block the sun, or any of the other natural cycles we know about.

You put them all into the system and you can't explain the warming.

And then you put this one little pinch of chili powder, which is just this increase in carbon dioxide and methane and nitrous oxide, and

the models give you the answers.

I'm just worried worried now that some people are going to, if they've only partially listened to this show, what they've mainly taken away from it is chili powders doing it, and it's actually affecting the amount of methane that we release.

And

then the number of hipsters are going, I want to go to the Arctic and sniff these gas bubbles.

It sounds great.

They smell great, by the way.

Well, that's what worries.

Can I just check, just for safety purposes?

So before we just get our straw straight down to find this, you know, released air from,

should we have any idea what it's going to be, or just a surprise?

Maybe it's methane, maybe it's oxygen mix.

Is there any danger in this before the hipsters die?

I'm slightly disappointed to say the honest truth is it smells like normal air.

But the bits of ice core that they gave us were chips of ice that had come from the very bottom of drilling this ice core.

And they gave us some in champagne to celebrate the fact that the ice core had been drilled.

And

all these bubbles,

these bubbles that had never been breathed by humans before.

And we're drinking them in this champagne, and they're all toasting it.

And it tasted like drilling fluid, right?

Dora,

how come you get all the telework with Brian?

I mean, I

mean, because we've both got wobbly middle-aged faces, so I realised that, you know, in terms of that, but I mean, is it just charisma?

There is just a look I give the camera every so often when he's doing his thing.

I just, he doesn't even see me doing it, and I give a little wink of here.

He goes again.

And the people at home feel trusted and loved.

That's all it is.

I'm doing what I, by the way, which I what I do, because people, I get weird kind of grief, including the why is your job just to interrupt pine cocks is

the most common complaint that I get about these kind of things.

Me too.

Yes, it is, because we have to do these things for time.

So I'm doing

what I believe I do and which is I'm shutting up and letting them speak

during Oz and I'm happy to do that.

I can merely offer this one observation on this topic, right?

Which is that we were doing tomorrow's food for Bibis One last year, and it was showed generally about food production and food science over the next while.

And we just kind of consciously went, could we be bothered going to the, is this happening or not?

And shall we just go and talk about what the implications for this?

Because it's always a question of what actually will this, how will this affect us in any huge way?

And we had discoveries about like grain and different types of grain and the yield,

like we basically have

chosen our grain sources to offer maximum yield at this particular temperature.

And if the temperature shifts one or two degrees specifically, the grain yield will tail off enormously.

So we're visiting a place in Nottingham, for example, that would look at different types of wheat and root structures of the wheat, whatever, in order to can we just shift into this wheat instead, because it's better at finding water four feet down rather than two feet down.

Yeah, I think we we were talking earlier, actually, Gabrielle was saying that the the the debate does seem to have moved on now.

You said you just come back from a conference in Chile, haven't you?

And you said that really the number of sceptics or whatever you'd call them in the sense that people who claim the world is that the climate is not changing, has diminished a lot.

It seems that there's broad acceptance now, so it's not even worth debating about that.

The difference of opinion now seems to be part very, part slightly on the cause, but mainly on how you what you do, as you say, how you mitigate it.

What is the impact?

But I just got back from this meeting in Chile where there was one climate sceptic to five of us saying we needed to act on climate change.

And I think the climate sceptic was overrepresented compared to the rest of the world.

And even he wasn't saying, he was saying, okay, I know it's happening.

Okay, I know we've caused it, but we should do something different.

And, you know, trust me, the heat is on.

The heat is real.

And in fact, one

business leader, the CEO of Unilever, Paul Poleman, was just lobbying for change, amazingly,

in Paris for the Paris meeting.

And he said the latest species to enter the endangered species list is climate change sceptics.

So that is over.

But

is that your assessment?

Because obviously

there's the odd kind of loud columnist in the press.

But in general, now,

in the meetings you go to, it's really even the so-called sceptics are sceptics about how you respond rather than is it happening.

The answer is yes, it is now, and that's clear.

And it's really all about what we do.

But actually,

as Dara said, that there is a component of if you accept that we are the cause, which virtually everybody does, then one of the things you have to do, as Tony mentioned, is reduce the CO2 levels in the atmosphere.

So, that requires you to accept the fact that

the so-called anthropogenic climate change is

even if you accept that humans are causing it, you can still say, oh, it's too expensive, oh, it's too difficult, oh, we should do it in the future, or we should delay.

There's still plenty of ways that you can try and pull back.

And I think that's where the real danger lies now, because the science is absolutely clear.

First of all, it's happening, and secondly, we don't know at what point in the future it will get really bad, but we do know that it will get really bad at some point.

And how big a gamble are we ready to take?

And that science is very clear, but you know, you can sort of say, Oh, don't be alarmist, oh, don't be so hysterical, let's just have a nice time.

And there's a whole load of inertia built in as well, because we're already, you know, they were talking in Paris about one and a half degrees.

We're never gonna, we're not gonna stop one and a half degrees.

I mean, there's just so much inertia, it's already built in.

There's already another 0.7 or maybe 0.8 of a degree of global warming built into what we have now if we emit no more carbon dioxide.

So it's not that it's happening, it's what do we do about it and when do we start doing stuff about it?

And the sceptics now are those who are saying, oh, well, you know, we're all doomed.

We really shouldn't do anything because it's too expensive and it'll cause the banks to fail again.

Well, yes, please.

What's the time scale, by the way?

So if we were to stop emitting all carbon dioxide tomorrow, and and you say there's still a 0.7 degree rise,

what's the response to that?

I'm not going to

breathing's allowable.

I mean, you can't.

If we all start holding our breath, it's a ridiculous idea.

Net.

Right, okay, good.

I just want to

say that.

It's the time lag, roughly.

Do we understand the time lag?

There are those who say that if we all started holding our breath, that would solve the problem, but actually

completely would solve the problem because there wouldn't be any more humans to pump it out, right?

There'd be no more industry to pump it out.

There'd be no more consumers buying crap.

You've just explained it.

Some of my.

Thank you.

Yes, I got it.

I was trying to get to the punchline, but that's right.

Again, he's a physicist.

But that doesn't work.

What I was trying to say is.

Sorry, I'll do it neatly again.

That will all get chucked out in the edit.

We'll keep the bit with Tony explaining the joke because that will embarrass him.

And

can you even tell I'm blushing already?

So if if we all held our breath, that would actually solve the problem, but I would prefer that not to happen because many of my best friends are humans and I kind of like to have them around.

So, we don't want to hold our breath, but we do want to try and do something about the amount of carbon dioxide that we're putting out.

But the time scale for

even if we switched off everything now and went to living caves, which we're not going to do, over the next few decades, we would still get more warming.

But

if we start to act now, we can actually reduce

the warming and the increase in carbon dioxide in the future.

And that's what we're doing.

Just one question about

the measurement.

So we hear one degree rise or two degree average rise.

What does that actually mean?

Is that the surface temperature?

Is it the air temperature?

Is it the ocean temperature?

What is that number?

So

in fact, that's part of the controversy.

Last year was the hottest year on record, and actually the first time that we hit one degree global average above the pre-industrial level.

So that's like we're halfway there to this two-degree target that you've probably heard a lot about.

So, what does that mean though?

Because you've got warming in the upper atmosphere, you've got warming in the lower atmosphere, you've got warming in the surface of the ocean, you've got warming in the deep ocean, you've got warming on land, you've got warming in different continents in different places different ways.

So, if you try to add all that together, it depends how you add it up, which years are the hottest, how you actually measure it.

And so, it's possible then to have some kind of controversy with it.

As soon as the World Meteorological Organization came out with last year was the hottest on record, immediately they started with, oh yeah, but oh yeah, but it depends on how you add it together this way or that.

But fundamentally, 15 of the 16 hottest years in the last 150 years have been since the year 2000, have been in this last century.

So that's how we know that it's really warming.

But

it's a complicated story because part of the reason it was so hot is because there's this El Niño phenomenon happening.

I don't know if you've talked about El Niño on the program before, but it's a weird kind of weather pattern that happens in the Pacific that actually changes the global average temperature for a short while.

It moves a warm pool of water around in the Pacific.

And what happens then is that you change the temperature.

The last time there was a really strong one was in 1998, and that was another big record year.

So you can also say, yes, it was really hot,

but you'd expect it to be hot.

You've got this El Niño thing going on.

When that goes away, it's going to cool down again.

And that's what people are now saying who want to try and challenge this.

But I'll go back to that point.

15 of the 16 hottest years on record happened since 2000.

You can explain one away, you can explain maybe two away, maybe three away, but you can't explain 15 out of 16 away.

Is heat unfortunate?

I know we're all talking about heat here, but is heat like a bad term to use in some way?

Because heat sounds like something we like, heat sounds like something we pay for, heat sounds like something that we and most of our time would actually have liked to have more of, as opposed to energy, let's say, that we're pumping more energy into it so we're getting more violent storms.

I know it is heat, but I but you know what I mean?

Like it is,

and selling this thing to people in terms of a lifestyle choice, which is is what it is.

Are there other ways that we could find it in terms of what actually will happen?

There'll be more violent storms, or that'll be, you know, the points where water will interact in the atmosphere.

That's because it's essentially about the movement of water.

Oh, sea level rise.

Those are ideas.

All of it's about the movement of water, because the energy has to go somewhere.

So it goes into water, it goes into clouds, it goes into watering, there are more violent rainstorms, sea levels rise, things like that happen.

Is that a better way of talking about it than necessarily heat, if you know what I mean?

There are people who say actually that they don't like using global warming, because warming sounds rather nice, and you sort of get into a nice warm bath, and so that's why they say heat.

But I like energy better because actually you don't really experience it, you get more heat waves.

But the most dramatic ways that you experience this change are in the form of making the atmosphere much more energetic.

So you get more violent storms and you melt ice, you melt glaciers, you melt ice caps, and you also heat up the ocean and that starts to expand.

And together that means that you get more sea level rise.

And then on top of that, you get in some places where you're evaporating more water.

So you get where it's dry, you get drier, where it's wet, you get wetter.

And especially this, where can we have access to water, which is already arguably starting to have effect in places like Darfur and Syria?

They've had, you know, then the effect is people start moving, and when people start moving, the rest of us get affected too.

So it's not just about, oh, it might get a bit hotter.

Dora, we're talking about the idea of, you know, we need to change things, but actually, individually, are we any good?

You know, it's almost like, well, I'm going to tweet a petition, I'm pretty angry about that, and then I'm going to play a video game, and then I'm going to, you know, and then we, as you were mentioning before, we buy our box sets and we do all these things.

So we look towards perhaps the big companies and go, well, they should be doing something, but I need these things because they're nice.

Yeah, I listen, we all like, we like the life we have.

I like my car, I like my flights,

I like bringing my car on a flight.

I mean, that's

indulgence.

You like a flying car?

Sometimes it's nice to sit in your car on a plane and roll down the window and go, I'll have the chicken, please.

It would be delightful.

But there is an end to which it's what life would we be willing to return to if we were sold that way to a certain extent?

Because we have a tendency to take for, I take for granted that there is fresh pineapple available at all times.

That I can feel like the my four-year-old enjoys fresh pineapple for breakfast, and I do go, Jesus, wet, this was like I, like one generation ago in Ireland, in particular, like orange juice was a starter.

That's how rare it was that it was a thing you had instead of the prawn cocktail.

And even then, it was squeeze, it was from a tub, and it was with you.

Anyway, but the so it is,

what is the thing that starts disappearing?

Is it like orchids at all times of year?

Is it like pineapples in your fridge in a plastic bag from our at what point do we just scale back?

Or is it simply that like

it's the flights?

My mother, right, they were tapping on immigration.

My mother's sister moved to America in the 50s, and then my mother didn't see her there for 30 years.

And then we went over, remember in 1979, I was only seven at the time, went over to visit.

And this is a chance for my mother to see her sister for the first time time in 30 years.

All of which is to say that we went to America in 1979 and when I was seven, and when I came back to school, and for the rest of the time I was in school, I was the boy who went to America.

And for my entire school career, I was asked questions about America.

And my opinion was about the elections coming up and the chair of culture.

Well, I don't see Carter who's going to win this one.

And because it was that rare a thing.

And whereas I know, obviously,

people don't all have two holidays a year and stuff like that, we still take for granted that we do a lot more flying in a way that our parents absolutely did not.

What lifestyle do we then return back to that people who were perfectly happy having about a generation ago?

And is that in some way what's going to happen?

And in some parts of the world, you know, the energy budget, so the energy, more energy is spent keeping people cold than keeping them hot.

You know, so

you can go ski in a refrigerated box in Dubai.

The things we do that are profligate with energy are amazing.

I remember sitting down once and calculating how many power stations were running just to make ice cubes to put in the men's urinals in American bars.

Right?

I mean, it's just crazy.

Oh, you know about that, Dara.

I do.

For many years, have many have been selling ice to urinals.

People said, You're mad, you owe me a dime.

And I said, I certainly will, my friend.

He's got to find his calculation out, though.

If you've done that calculation, have you actually done the calculation?

How did you, yeah, well, let's follow that a bit.

How did you estimate the number of urinals in the United States?

Okay, so

how many people are there per bar?

Right, so a thousand people per bar.

Right,

then you take the population of the country, yeah, yeah, that gives you the number of bars, yeah.

Then you have the number of kilograms of ice, yeah, you know the um

enthalpy of fusion of water, you know how far you have to cool it, you can work out how much energy is needed.

You need to know the average temperature of urine as well, I suppose.

Well, it's no, it's pretty much thirty-seven degrees.

Yeah, idiot.

He in College of Brian has never even checked the temperature of his urine.

That'd be biology, that, would it?

I want to know where they put the urine.

No, no, it's in it's in the urinal to stop the smell.

I d I did not know that, right?

Just it's it's not that common a thing.

It's not like we glide around having our urine cooled for a second.

I I in the car have a urine cooling unit.

So when I drive it onto the plane I can have my urine cooled for a flight.

How many power stations was it ultimately, John?

I I'd have to sit down and do the calculation.

Look, you can't go through the whole the ice, the urinals, these thousand people pubs.

Just just just give give me a minute or two.

None of us have even actually heard of this ice.

I mean, we don't really much.

This ice in the urinal, it seems to be some kind of Narnia urino.

People.

I'm not sure.

You are.

Dora, you're an innovative scientist.

He's becoming comedy guest now, okay?

You've got to take the ice out of the urinal.

That's the only thing we can say.

World leaders standing at urinals going, no, really.

So here we go.

The ice in the urinal has now been replaced by a piece of plastic, a polymer,

that is tuned to emit a fragrance when 37-degree fluid hits it.

So now there's no longer an odour.

We're all right then, man.

So this is the problem solved.

Is this what came out of the Paris climate change?

No, no, no, no, no, sorry.

But then you need to do the energy balance of how much does it cost to make the plastic, to infuse it with the fragrance, versus how much energy does it cost to make any ice?

Kind of there.

So there we are.

Aren't they the sort of questions you do with every day?

Yeah, so yet again, the

casual listener has found out that the two causes of climate change are chili powder and urinals.

That's it.

Great.

What an educational, final episode this has turned out to be.

But talking about,

you were at the Paris Climate Change element, so

this

we saw the headline, you mentioned it earlier, the two degree goal and the one and a half degree aspiration, which you said was probably beyond us already.

So where does that figure come from, that that two degree it's become a totemic figure almost, hasn't it, for climate change?

We have to stay below two degrees.

In a way,

here's one of the things that you have to try and set a target of some kind.

And there's no science that says if you go to one point nine nine degrees, everything will be all right.

And if you go to two point zero one degrees, everything will go horribly wrong.

It's not a cliff like that.

What it is is it's a kind of estimate, if you like, that if we go if we go beyond two degrees, then the probability of really bad things happening starts to accelerate and starts to increase.

And some of those really bad things are the things that keep me up at night.

They're the sort of nightmare scenarios, the tipping points, if you like, where instead of increasing in temperature and increasing in a way that we might be able to adapt to and actually do something about, then something falls over a cliff.

And so it can be things like in the northern permafrost, right, this is a stretch right across Siberia and across northern Canada where the soil is full of carbon.

We don't even know how much carbon there is down there, but we know it's an awful lot.

Twigs and leaves and stuff that's been trapped in there and frozen.

And as it's starting to thaw, and it is starting to thaw, it's a bit like you turned your freezer off and everything in it starts to rot.

When it starts to rot, it gives out carbon dioxide or methane, right?

Greenhouse gases.

So, what happens is you warm it up a bit, starts to rot, gives out greenhouse gases, gets a bit warmer, starts to rot more, gives out more greenhouse gases.

And the whole thing accelerates until you end up with this positive feedback and a right old mess.

And the sort of thing where it wouldn't matter what we did, we'd just have to dance around the bonfire.

Now, you might ask me what temperature that will happen at, and the answer is: not only do I not know, but we don't know.

Nobody knows.

And as we go above two degrees, we just get likelier and likelier that things like that can happen and take us to a place where the climate could be very, very different

and the Earth wouldn't really care.

But us humans trying to live on it would have a real problem.

And so, you know, the whole saving the planet thing is kind of an anathema because because the planet's going to be just fine.

I mean, there will be a planet and it will have stuff living on it.

It just won't be us.

And it'll capily just kind of keep going round and round for quite some time.

I'm sorry, this is the one thing I was saying.

Why won't it be us?

Why, and I don't mean that flippantly, and I don't mean that in any kind of necessarily auto-sceptic kind of way, right?

Why won't we cope?

Why, what will happen that will be impossible for us to continue to survive, to change, to just survive within a different climate as the as this occurs?

Well

y

you've already mentioned some of it, which is food production.

So so if the if the climate changes, then the cultivars that we have now that we all depend upon uh won't work.

So if if the climate changes quickly and the temperature rises quickly, we won't we won't have the right plants to to to grow the food that we need.

They'll need different amounts of fertiliser, different pests will come in.

So there'll be monster food shortages and they cause wars.

And then there'll be water shortages, and they cause wars.

And people will try and move from one place to another, and politicians will start putting fences up, and that'll cause wars.

And so, what will most likely kill us off to a great extent is conflict.

I agree that that's a possible future.

I don't think it's the one we're going to get to.

You just said, why won't we cope?

And Dara, I think we will will cope, actually.

I really do think we do.

And one of the things, one of the reasons I think that I've been working on this for twenty years, and for twenty years I've been banging my head against a brick wall, saying things that the science isn't telling us and not getting absolutely anywhere.

And now in the last year, my phone's ringing off the hook from really unusual places.

We've heard we need to act on climate change from military leaders, from business leaders, from the Pope.

You know, we and we've also and in the the meeting in Paris, the reason I was really excited about that meeting.

And in fact, if you add up all of the things that all the different countries committed to, it's not nearly enough for what we need to do.

However, the reason I was excited about it was all the stuff that was going on behind the scenes and on the side.

Because Paris was actually

full of businesses and it was full of trade unionists and it had NGOs and they were all working with each other and they were all putting pressure on the politicians saying, we are already doing this.

There's this fantastic moment.

Cristiana Figueres, who is the head of

the whole enterprise of trying to get steer the United Nations to deal with climate change?

She actually read out a list of all the announcements that have been made by the businesses and then by the cities, the mayors, and all the other people.

And it was about five or six pages.

It took her about 15 minutes just to say, These are all the things that are already happening, all the announcements that have now been made.

So it's just this massive momentum.

And when, you know, I think when humans, as I said, many of my best friends are humans, right?

So, and I think we're quite, we can be creative, we can be inventive.

When we decide to do it, we do.

So I think we will cope.

Is that a reaction to

data or a reaction

to the to an based on an acceptance of the modelling and acceptance of the science?

Because we we've seen this data, as you say, it is quite obvious now that we're getting hotter years.

I think people even see it in their own back gardens, as it were, and they see the probability of extreme weather feels as if it's rising.

So is that what's causing this renewed acceptance?

Or is it really an acceptance of the science and the politicians coming together and saying, No, I actually believe that your models are now good?

I think it's a combination of accepting the changes that we're already seeing, and it's actually already with us, and also understanding better the potential of what could come if we don't deal with this.

And then, if you look at many of the, like I said, the big businesses, they understand that they need to get their energy from somewhere, they need to get their water from somewhere, they need to be able to deliver to people who are actually able to buy the stuff that they that they they sell.

In some cases, it's reputation, but in other cases, it's just we won't be able to operate.

We need to make ourselves ready for what's coming, or we won't be in business.

I stood with Brian Gilrari on a on a platform at the Royal Society, and he's the finance director of BP, and he was advocating a carbon tax.

So, this was a company saying we need to tax, an energy company saying we need to tax carbon because they realize that they have a stranded asset.

There's all this stuff under the ground that they own that they can't get out and dig, they can't dig it out and burn it because we can't afford to.

So, we need to change our business practices to allow this changing lifestyle, right?

And so, business as usual in the climate change sense ain't going to work, but business as usual in the business sense ain't going to work because you need to have an unfair playing field, right?

You know, we signed up to

the UK, signed up to making all these changes, and then a week later took away the subsidy on solar panels.

Bonkers, right?

You can't have, if you're not paying for the damage you do by fossil fuels,

because all you pay for is digging it out of the ground and burning it.

You don't pay for the loss of immunity for future generations,

you don't pay for the environmental change, then

it's easy to compete with a solar panel that doesn't have all those advantages in the economic sense.

So we need to take those advantages, those economic advantages away from our profligate use of fossil fuels and give those economic advantages to renewables, to mitigation processes, to technologies that will take carbon dioxide out of the atmosphere.

We need to give them an advantage, a tax break, a subsidy.

After what changes people's minds won't be necessarily evidence or political will, but market forces.

If the prices of things change, then people will shift into what they're doing.

The most interesting announcement in

some ways was Coca-Cola, who went on saying, we have to move three bottling plants because water isn't coming to where we used to come to.

So we can't bottle here anymore.

And that is a massive financial decision made by a large corporation, I think.

And so you're going that when that starts affecting people, that will make people, even places in America where people are very, very business-minded, I presume.

Am I wrong about that?

I'm sure you're quite right about the bottling plants.

I just think the economic driver can't be the market as we understand the market now.

It needs to be a regulated market.

I think I'm going to jump in here because

it can be we don't have enough water, so we're going to change.

But the businesses that I'm working with are actually, they're actually being more leaders, I think, than many of the other sectors, and certainly more than politicians.

So, for example, Apple, I just met the

Apple has hired as their director of environment Lisa Jackson, who used to be the head of the Environmental Protection Agency and she's the one who got carbon dioxide called a pollutant in America.

She's now head of environmental stuff at Apple.

So 100% of Apple's operations in the US are now fully renewable energy sourced, right?

100%.

80% of their worldwide operations are

come from renewable energy.

And the way that they've done it, and they're trying to get the last 13%, the way that that they've done it is where there wasn't any renewable energy.

They partnered with a solar energy company and they built it.

So Apple has been building solar energy plants around the world so that they can source renewable energy.

Google's going to do the same thing.

Look at what IKEA, I love this actually.

IKEA's head of sustainability, which is actually very significant in IKEA because they build sustainability into their model, has just said, we want to go more into a circular economy instead of just selling more and more stuff.

He said, I believe that we have reached peak curtains.

So

I love that phrase.

Anyway, it's interesting because

one of the things that I get depressed about, and you mentioned it, is the lack of political action.

It seems large-scale global politics is an extremely difficult thing.

But what you're suggesting, in fact, is that the politics is essentially being circumvented in a sense by business.

Not circumvented.

Because if you look at what happened in Paris, I think that what happened in Paris managed to

get it because

this pressure was going on on the politicians and the policymakers from the businesses and all the other places.

But they also managed to do it.

And I think there's a lot of fantastic policy that happens outside the kind of

the main centers.

We found that the best policy is happening in cities, in regions, in states, and behind closed doors, and

where policymakers are talking to NGOs and they're talking to businesses and they're saying, What do we all need to do to make this happen?

And it makes me very, you know, if you look in Washington and you see the way that the Congress, they're just all battering their heads against each other and getting absolutely nowhere.

It's infuriating.

But in the meantime, in the US, there's states and regions, there's associations of mayors, they're all just doing it anyway.

And in the end, it's not going to matter what Congress says or does.

And so I don't think policy making politicians have a really hard job trying to get around all the kind of all the things that are put in place to stop them changing anything.

And I think the ones that we talk to are really happy to have leaders from business come along and say we can help you do it.

And they're helping in the right way now and not the wrong way.

And all those businesses you mentioned are big high end, high added value businesses that can afford to do these things, right?

But you know, if you look at a loaf of bread,

forty percent of the embedded energy in a loaf of bread, so all the things that have been put in there to make the loaf of bread, forty percent of that is to produce the fertilizer,

right?

To take nitrogen out of the air, make it into ammonia, make it into fertilizer, take it to the farm.

Because all the plants we eat, all this, all our cereal depends on fertilizer, and that fertilizer depends on energy that has to come from somewhere.

And at the moment, it comes from coal, oil, gas, nuclear.

But it really, that fertilizer either needs to come from the sun

by some solar-powered process, or from the

seven billion getting on to 10 billion fertilizer producers that are called human beings.

You mentioned energy use there.

The way that we generate energy is obviously of concern and one of the major contributors to CO two emissions.

So what is your feeling about the way we should be generating energy?

I think I hear a lot, especially from people who are saying we shouldn't act on this, that there's a lot of subsidies going into renewable energy and there shouldn't be.

What people don't really know is how much a subsidy is going into fossil fuel industry around the world.

And in fact, if we just took away all the subsidies, then that would be a a very big help to start with.

That would help to level the playing field.

But

in terms of what needs to happen to make the energy, I mean, every energy company that I've been working with, and the utilities as well, and the people who buy their energy from these companies, are all talking about the energy transition, the energy transition.

Everyone knows we need to do it.

And the only controversy is how fast we do it and how we make it happen.

So it's utterly clear that it's happening.

And then, but how it happens has to be the policy makers have to put this kind of system in place where they don't keep pulling the rug out from under, you know, we're going to do it this way, then we're going to change it and do it that way.

The businesses need to figure out how they can change their way of making money so they can move from one to the other.

And the really clever people need to come up with brilliant new inventions that change the whole landscape.

And I think one of the ones to look out for, by the way, this is, I know this is a comedy programme, so it's not very funny, but batteries, storage, that's actually the thing that's going to make all the difference in the world.

If you can make energy in one place, stick it in your pocket, or on your ship, or in your car, and take it somewhere else, that will change everything.

And then it won't matter what the governments do or anyone else.

It'll just put it.

If you can do it cheap enough.

If you can do it cheap enough.

If you can do it cheap enough.

Actually, the thing that will make a real difference is if we can learn to do what plants do, which is to store the sun's energy as a chemical bond that we can then release somewhere else.

Because actually,

burning stuff is brilliant.

So, a chocolate chip cookie, right?

Same energy in a chocolate chip cookie, you'd need

250 AA batteries.

Okay, because it's real, most of the mass for the combustion comes from the air.

So, nature, photosynthesis,

turning sunshine into chemical bonds that you can subsequently reuse, can be a closed system.

And you just use the carbon to kind of go round and round and round and round.

And that's what we need to learn to do.

I like the fact we're just going through your shopping list today: bread, cookies, ice, urine freshness.

Well, you've mentioned talking about those things.

I wonder

there hasn't really been met what nuclear, which has been, you know, what about that?

You know, renewable is talked about a lot, but there have been over the last 10 years, more and more people have said, well, actually, you know, nuclear might be one of the perhaps working in tandem as well, renewable and nuclear.

So what do you think?

So for me, the really logical thing to do

would be to build either a biomass plant or a coal-burning power plant next to a nuclear power plant.

Use the nuclear power plant to split water.

Yeah, get the heat and the electricity, but split some water, and then use the burn the coal, burn the biomass, and combine the hydrogen from the splitting water with the carbon dioxide that comes out of the chimney to make methanol.

You've got a new fuel that's a liquid fuel, use the same liquid infrastructure, you could use every bit of biomass twice.

Getting planning permission for a biomass power plant next to a nuclear power plant,

not going to happen.

Right, so you're a solution to me.

It's a really, really, well, it's a really logical solution, but you know, we have to put them all in the social and economic context.

So yeah, absolutely.

The soul of the future has to be sunshine, right?

You know, we have to go back to being an economy that's powered purely by sunshine, because that's what gives us this energy balance.

We already are.

We already are.

Everything, all the energy comes from the sun.

They were fossilized.

Yeah, they were fossilized.

But we can't afford the fossils anymore, can we?

That's the issue, right?

So, you know, to be fair, the sun has always and always will provide almost all of our energy, not all of it, it actually.

Because that's one of the things.

One of the things I actually love about nuclear power is that you're releasing energy that was trapped in a supernova, right?

Yeah.

So

in fact, nuclear power is the only source of energy on Earth that is not powered by our own sun.

Geothermal.

Geothermal.

Geothermal.

Oh, no, you're right.

Okay.

Nuclear power and geothermal power are the only two sources of energy.

So find the energy.

Finally.

Amongst the many forms of energy.

Right, let's build it up then.

So tidal, geothermal.

Well, we're going to argue about tidal tunnels.

So, you're going to say tidal's not.

The sun and the moon.

Right.

Hang on a minute.

How many challenges?

That wasn't a supernova.

That was not a supernova.

The moon wasn't.

Whereas geothermal is half supernova.

Yeah, but the moon is.

Anyway, what I'm trying to say is,

no, so

where should we get our energy from in the future?

And obviously, it needs to be stuff that we can renew ultimately.

And some of the challenges with nuclear power are: it's not technically renewable because of the stuff you put in it, you have to mine it, and also you have to figure out what to do about the waste.

And also, it has a potential both for nuclear proliferation and for

accidents.

And I think that with modern-day nuclear plants, you can do a lot about the accidents problem, you can also do a lot about the danger of terrorism.

I think if you if it depends whether you're already making nuclear energy, if it makes sense, because if you if you're a new country starting with a nuclear waste problem, that's a big problem.

Whereas if you're if you're like the UK, where you already have a nuclear waste problem, you can add to it a little bit and you can make a lot of energy.

And so that makes a bit more sense, I think.

Economically, it's very expensive.

And there are plenty of people who say you shouldn't put the money into nuclear, you should put the money into solar and to wind and to tidal and to the other things.

It'll be cheaper, you'll get it better, and you won't leave something for future generations.

And I think the answer for nuclear is it depends on the circumstances.

But I don't think we can rule anything out of the mix.

I think we need everything to solve this problem.

And we are in complete agreement there.

One of the things we need to think about is

the concern we have about nuclear is the waste and the real the waste problems are actually the waste problems from the legacy of nuclear weapons and that technology leading to nuclear energy.

If you just do nuclear energy, then the waste problem is much, much smaller than our legacy nuclear waste.

Are you optimistic, Dara?

Because it seems that you need a

In order to get political action, you need a shift in public opinion, which seems to have happened to some extent.

But are you optimistic about the future here?

I think we can deal with this.

I think the problem could be better set than it has been.

And

I think once we get past the hump of there being people who just want to put fingers in their ears and say this isn't happening

and

begin to regard them as flat earth and there was no moon landing, people,

and not as all of that, but I think you get into a more interesting discussion.

I'd also like to get to the point where the two of you don't look as you occasionally do, they're nervous to be seen to disagree as if that somehow would be simple.

Oh, sorry, but do you know what I mean?

That there'd be that there isn't consensus because

that there should be a healthy debate occurring within these fields, and that you may have different views about it.

And we disagree about all sorts of things.

No, we don't.

Do you think it's something interesting you said there?

Because you say we shouldn't

There is nothing greater than seeing two scientists do a joke together.

It's one of my favourite things.

The power of that reaction as you that is a way that could power, I think, the future of the

uh so this is uh that I think we'll end the discussion on that.

Dora, would you like a final bit?

Can I ask one very, very quick question?

If you could invent a thing in the morning, silver bullets, if people were putting money into things rather than let's say returnable rockets or Wi-Fi for all far-from places, which is the which is the

billionaire businessman's current choice of thing to invest in.

What would be the thing?

You say batteries, rather than is there, is there a can you sink carbon?

Can you, what would be a

storage, and it doesn't, when I say batteries, it can be batteries of any form.

It might be something that looks like a plan, but any way of storing the energy and moving it around would change everything.

And then that is one of Elon Musk's great

billionaire businessmen do do that, then there's the

other

billionaire businessmen are available, I should say.

We asked our audience a question, and that question was: what do you think are the most nightmarish possibilities for planet Earth in the next 100 years?

Tim Morgan says, The moon has moved so far away that the BBC acts the programme stargazing live because, with the moon gone, they have nothing else to talk about.

Oh, cloud cover.

There's one: the planet is taken over by immortal strawberries.

They run out of reasons to regenerate the doctor.

I don't know how I'm going to tell my eight-year-old, by the way, there's no series this year, so you better not listen to this.

You're talking about every set homework, a Radio 4 series.

This is a proper Radio 4 answer.

It's like either of our daughters passing their driving tests.

That's the end of the series, and we're going to be answering your emails and letters in special over on Radio 4 Extra in the next few weeks.

And then we're going to be back in the summer.

And if you do, by the way, write into the Radio 4 for an extra show that we're doing about various things we've dealt with, please do not start your letters with why, oh, why, oh, why?

Because Brian thinks that's the beginning of an equation he doesn't understand.

So, thank you very much, and goodbye.

Now, nice again.

My story goes: drug addiction.

I ended up getting clean.

Okay.

And so, throughout that process of getting clean, I started volunteering for the state prison and carrying the message of recovery.

You know, you meet a lot of people, right?

And convicts need a chance too.

And so, giving these guys a chance was an opportunity for me.

They absolutely have turned their life around and made a difference.

Season two of Beyond the Moon, a Ditch Witch podcast, is streaming now on your favorite podcast platform.

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