Is 1.5 still alive?

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Hello, lovely, curious-minded people.

We have almost made it to the end of January, and it's the last inside science of this dark, cold month.

So we're scrutinizing the global temperature.

We will be asking what is so significant about the figure 1.5 degrees and some brand new clues about how life began on earth from a very old piece of space rock and i join you today from a spacious shiny bbc studio in salford where as usual the greater manchester sunshine is glinting through the windows and i'm joined by new scientist writer graham lawton who's going to unpick a very busy week in science news hello graham welcome to the studio thank you for having me um and what have you got for us a bit later give us a teaser well i'm going to talk about two stories with really exciting interesting top lines but when you dig down turn out to be something really rather different but no less interesting for that.

And then we're going to talk about a surprising discovery about surprising discoveries.

Excellent.

I love it.

Well, we will be back with you soon.

Feel free to get yourself a cup of tea and sit back in the meantime.

Now, though, 1.5 degrees C.

It gets mentioned again and again at UN talks, in the news, because this is the number we talk about when we talk about climate change.

Last year, it was confirmed as the hottest year on record, and perhaps most alarmingly, the average temperature on the planet broke through that symbolic 1.5 C mark.

But to work out how significant that is, we want to ask: what does 1.5 degrees actually mean?

Where did the figure come from?

And since we already warmed up the world by more than 1.5 degrees, does the number even matter anymore?

So, earlier today, I put all these questions and more to climate scientist Mark Maslin and environmental psychologist Lorraine Whitmarsh.

Can I start with you, Mark?

1.5 degrees, where did that number come from?

So, the the importance of 1.5 is it is enshrined in the Paris Agreement.

And this is where 10 years ago, the leaders of the world said, we will keep climate change to two degrees and we will have an aspirational target of 1.5.

And the 1.5 came from some beautiful politics of the EU, the UK and the small islands nations who were then trying to push for greater commitments.

What's interesting is the science says that between 1.5 and 2 degrees, there's a lot of other impacts that could happen, which could be catastrophic for many areas of the world.

What does 1.5 actually mean?

Just spell that out for us.

So, in many ways, 1.5 is symbolic.

What it says is the huge amount of climate change that has happened around the world.

And people go, oh, 1.5, that's not really going to affect me.

However, when you do it on a planetary scale, it's firstly putting a huge amount of energy into the system, which means the climate system is speeding up.

But it also means that the extreme climate events are increasing.

Like the wildfires in California, you have the floods in Spain.

But also, if you think about it, two years ago, we had a 40 degree heat wave in the southeast of England in July.

So this was 16 degrees warmer than it should have been with a global 1.5 degrees warming.

Lorraine, Mark talked there about beautiful politics.

You are engaged in trying to communicate with the public about climate change.

Do you find that 1.5 figure helpful or hindering?

I think it's not really a figure that comes up very much.

More often, we're talking about it in terms that relate to people's everyday experiences.

And so, sort of changing weather patterns and specific risks around kind of floods, heat waves, and how people can adapt and the role that they can play.

So, actually, those sorts of global targets and sort of some of the more technical language around climate change, we wouldn't tend to be conveying to the public generally.

Kind of feels a little bit out of reach, perhaps.

So, Mark, can I just dig into 2024, hottest year on record?

Is 1.5, that target, officially dead now?

Where are we?

Oh, so this is a huge problem because the definition is the average midpoint of 20 years.

So even if we passed the 1.5 degree limit today

we wouldn't officially be able to tell you that until 2035.

Can I just pick you up on that?

The average midpoint of 20 years.

So that means we have to get an average temperature every year for 20 years before we can say that that's the point on the graph has actually gone up beyond that point.

Yes, and that way lies madness.

So this is just, again, because it means we're 10 years later.

we go oh no we did pass it 10 years ago other people have suggested we can use trends and the one I most like is use the last 10 years of climate records and then we can use the next 10 years of climate model records and then we put those together and we can then see the average of the real and theoretical 20 years and then have a midpoint and that makes much more sense.

Can I ask you to project what that will show us in a couple of years?

Do you think we're beyond it?

So I think in the next couple of years, the temperature of the planet will be such that we'll look back and go, yeah, we have gone through the 1.5 limit.

That doesn't mean that we can't go backwards.

This is not a one-way street.

It's just we have to act.

Talking about, you know, we could go back, seems a good time to ask you both about what's been happening this week.

Because, you know, this week we've seen a Heathrow expansion of third runway put on the table, and my inbox has been flooding with environmental groups saying that this is a catastrophic decision.

The LA fires have been officially linked to climate change.

So does raining things back in below 1.5 again feel fanciful now?

I think it's deeply unrealistic that we're going to change as rapidly as we need to.

And this is why there's a lot of hysteria about the 1.5 limit, because of course scientists have been using it as a way of beating politicians going, you have to keep below this, you have to keep below this.

And of course, we've gone through it.

And so the problem here is, what do we say next?

Oh, don't go past 1.6, don't go past 1.7.

So there's a problem psychologically with these sort of limits.

But if we go back to something like, say, Heathrow, Heathrow is a really interesting microcosm because if we look at the aviation industry, it's going to grow at 4% per year.

So therefore, we need to change the whole industry.

We need to decarbonize flying, not stop an airport expansion, because there are something like 500 new airports being built at this moment in time around the world.

Mark, you touched on it a little bit.

Do we set a new target?

Do we need to change our threshold now?

I don't think we need a new threshold.

I think that 1.5 is still going to be the gold standard.

And if we go above it, what we're going to be saying is we have gone beyond where we want to be and therefore this is really bad.

What we cannot do and we cannot allow the politicians to do is to switch to, oh, but in the Paris Agreement we mentioned two degrees.

So why don't we just kick back and don't worry until we get to two degrees?

No.

So I suppose it's worth saying that the 1.5 degree target is one policy target that we have, but there are also other ones.

Within the UK for example we have carbon budgets that we're trying to keep within and these are amounts of emission reductions that we're trying to make over a period of years.

And so those are really critical markers of our progress in decarbonising society.

So I don't think we need to be sort of overly focused on the 1.5 target.

That is important, but also thinking about these different targets and these different measures of progress is also important.

Well, it's a bit more immediate, isn't it, to measure emissions as well.

So do you think that's more useful?

Yes, I do actually.

And I think as well, having those kind of windows of like a period of years in which you're trying to bring down emissions is helpful.

It provides the flexibility that policymakers need actually, because there's so much uncertainty in how to decarbonise.

We're still learning as we go.

And I think providing those windows actually is quite useful.

And Lorraine, how does all of that kind of difficult news when it comes to, you know, news that doesn't seem to stack up with our targets to reach net zero and to rein in emissions, how does that affect people's mindset, the ability to engage people with climate change?

It fundamentally undermines their confidence that the government is doing anything on climate change.

It disempowers them because they don't feel that they have any agency to be part of tackling climate change.

We did some interesting research a couple of years ago actually where we kind of compared people's response to COVID with people's response to climate change and what we found was that people inferred the severity of COVID from the government's response to it and they said we've never had lockdowns before.

This must be a really bad risk.

With climate change, then we hear people going, but it can't really be that bad, is it?

Because otherwise, the government would be doing more.

They would be taking it seriously as if it was an emergency.

That sounds like two almost diametrically opposed, really difficult attitudes to sort of engage people with, feeling completely hopeless and also feeling, oh, well, it clearly isn't that important because otherwise there'd be urgent action.

How do you tackle that as a psychologist?

Yes, we have been calling for the government to develop a public participation strategy on climate change, which thankfully they are going to be doing this year.

And as part of that strategy, they need to demonstrate their leadership and the action that they're taking on climate change and join the dots for people to show: yes, we are reducing emissions across all these different sectors and in these different ways, but crucially, also show that the role that people can play in tackling climate change because where we're going to have to increasingly make emission reductions is on the demand side.

In other words, how we use energy, how we travel, how we eat.

So we really need to show how people can be actively involved and make it easier for people.

Thank you, Mark Maslin, Professor of Climate Science at University College London, and Lorraine Whitmarsh, environmental psychologist at the University of Bath.

Now, Graham, you are a science storyteller, a seasoned science storyteller.

So listening to that, would you say the famous, perhaps infamous 1.5 C, that figure, has it helped or hindered your storytelling?

I'm not sure yet.

I mean, it's actually climate stuff is really hard to do well, not because there isn't stuff to report, because there's always new things, but essentially the story hasn't changed for 20, 30 years.

So it's really hard to engage people because you see a climate story and you think, well, I know that that's going to be kind of bad news.

It's going to be hard to swallow.

And I kind of already know what the story is.

I think 1.5 in some ways is it was a symbolic target.

Getting there, I think, might, well, I'm kind of hoping it'll be a wake-up call, but I dread that it might just inspire hopelessness and nihilism.

But in terms of storytelling, at least it gives us an excuse to go back and say, like you've done today, what does 1.5 mean?

What do we do now that we've gone past it?

And is there any hope of bringing ourselves back to it?

Yeah, quite.

Well, thank you very much, Graham.

We'll be back with you shortly.

Sucks!

The new musical has made Tony award-winning history on Broadway.

We demand to be home!

Winner, best store!

We demand to be seen!

Winner, best book!

It's a theatrical masterpiece that's thrilling, inspiring, dazzlingly entertaining, and unquestionably the most emotionally stirring musical this season.

Suffs!

Playing the Orpheum Theater, October 22nd through November 9th.

Tickets at BroadwaysF.com.

And as we're dicing with the livability of this planet, this week we're a step closer to understanding the origins of life on Earth, thanks to some specks of dust scooped from the surface of an asteroid called Bennu.

Back in 2020, NASA's audacious OSIRIS-REx mission successfully grabbed a sample of rock and dust from the asteroid's surface with a robotic arm.

The precious cargo was then dropped off in the Nevada desert in September 2023.

And a select group of scientists from around the world were given tiny pieces of the sample to analyse.

Two of those scientists join me now.

Sarah Crowther from the University of Manchester, who is in the Salford Studio with me.

Hi, Sarah.

Hello.

And Sarah Russell from the Natural History Museum, who is on the line from Washington DC because she is on a Bennu press tour.

Hello Sarah.

Hi Vic.

Hello.

Two Sarahs, one asteroid.

I'm going to start with the studio Sarah, Sarah Crowther.

How much of Bennu actually came back to Earth and where did it go?

So the total mass that was collected from the asteroid was a little bit over 120 grams.

Now a small fraction of that will be distributed to, as you said a moment ago, scientists worldwide, but a large fraction of it will actually be retained for future generations to study, you know, maybe in 50 years or more.

So

can I ask each of you not to pick planetary scientists Sarah against planetary scientist Sarah, but how much of Bennu did you each get?

We've probably got a few milligrams total.

So we've got about a teaspoonful, which was about 100 milligrams, but this was actually to share out amongst several different groups.

So you went hogging more of the asteroids?

We weren't hogging it all, no.

Sarah Russell, I'm I'm going to call you DC, Sarah.

The first analysis of this incredibly precious piece of rock that you were involved in has just been published.

Before I get to the results, can I ask you what you were doing to this sample, what you were analysing, what you were looking for?

So we wanted to find out what the rock was made of and from that try to reconstruct the history of asteroid Bennu from its formation right at the very beginning of the solar system and what's happened to it since.

We looked at it in enormous detail.

So, we did a whole series of measurements.

We did some CT scanning to enable us to look on the inside of each of the grains brought back from Bennu.

And then we did some electron microscopy to look at the grains really close up, which is we really kind of needed to push our equipment because the grains were so, so tiny.

They were typically a micron, which is a millionth of a meter or less.

So, what were you looking for, and what did you find?

Firstly, we wanted to know what Bennu was originally made of.

And what we found was it's actually really hard to find these primordial grains that it was made of because it's experienced so many changes since it formed.

And in particular, we found it had been completely altered by water.

So, we think that when it first formed, it formed from a mixture of rock and ice, and then it gently heated because it was slightly radioactive, and the ice melted, melted.

And that completely transformed the minerals it was originally made of.

And what we found was that it formed mostly clay minerals.

But the thing that we were reporting today was that we found this whole sequence of salt minerals.

And we think that they formed from pods of salty room temperature water.

So that tells us there was actually, you know, these little bits of liquid water, briny water inside the asteroid.

And these would have been great places to form new organic molecules.

So it may have something to do with how organic molecules can start to form.

Right.

So there's some teasing words in there, isn't there?

Organic, water.

These sound like some of the ingredients for life.

Does that mean that the ingredients for life were in Bennu?

Yes, that is exactly what we're saying.

So we don't find any evidence for life itself in Bennu.

We have to make that like really very clear.

But exactly, all of the ingredients needed to cook up life were on Bennu.

So water was there, which is obviously essential to life as we know it.

The salts themselves also contribute other bio-essential elements.

So we find a lot of phosphates, for example, which make up the backbone of DNA.

So we've got all these sort of Lego bricks that make up life.

And we think that asteroids like Bennu may have impacted the Earth in its earliest history and brought these ingredients to our planet.

Wow.

So the Lego bricks of Life.

Studio, Sarah, there's another paper published this week.

I know you weren't involved in that specific study, and your analysis is yet to be published.

But how does that add to all of this evidence about the significance of Bennu and these ingredients for life?

So, as Sarah just touched on,

the other paper was looking at the organic compounds.

So these are compounds that are built around chains or rings of carbon atoms.

And they found amino acids, which are essential for making proteins.

All living things use amino acids to make proteins.

And they also found the building blocks to make DNA.

And what I think was really interesting is the amino acids.

So amino acids form two types of molecules.

If you look at your hands for a moment, we have a left hand and a right hand that are mirror images of each other.

And you can't superimpose one hand on top of the other.

So the amino acids form molecules that have the same chemical formula, but they're mirror images of each other.

And all biology on Earth uses what we call the left-handed type of the molecules.

And we don't really know why this was.

In some meteorites, we found an excess of the left-handed molecules.

So this might have suggested that maybe in the early solar system, for some reason, there was a preference for the left-handed type.

But in the Bennu samples, they found a 50-50 mix of the left-handed and the right-handed type.

Wow.

So that kind of questions that theory.

This was one of the most exciting and puzzling findings because it's not what we see in meteorites.

So we have this whole collection of asteroids already on Earth and in the form of our meteorite collection.

A meteorite is any natural extraterrestrial object that's fallen to Earth.

And the fact that they don't have this racemic mixture of equal amounts of left-handed and right-handers makes us think that maybe they tend to become contaminated with terrestrial life.

And what that tells us is we really needed to have this space mission to go to an asteroid and bring back this very pristine sample to enable us to be able to look at what an uncontaminated asteroid looks like.

It's fascinating.

Thank you.

Sarah, can I just

studio, Sarah?

Bennu's journey in terms of scientific analysis is nowhere near over, as you were alluding to earlier, but you're doing your analysis.

right now.

I know that you can't talk about it yet, but can you give us some hints as to what you're looking at?

So, I often like to say that I zap space rocks with lasers, but then people think I'm zapping my laser up into the sky.

I'm not.

We're doing this all in the lab, and we're studying the gases that are trapped inside the pieces of the asteroid.

And one of the things we will try to do is determine an age for the asteroid.

So, that will then help us understand more about the physical processes happening in the history of the asteroid.

So, how old do we think Benner is?

We talk about billions of years.

Yeah, it'll be about 4.5 billion years, but we can probably tie it down a bit more than that with the analyses.

Right.

Sarah, you touched on the fact that a lot of this will be, a lot of this sample, this tiny sample, is going to be saved for future analysis.

What else do we have to discover?

Because I know that hundreds of scientists are already looking at this material.

We don't know, and that's the beauty of having it on Earth.

As we've got the samples on Earth, we can save some of them for future generations who might use them to answer questions we've not thought about yet using techniques that we've not even developed yet.

And this is exactly the kind of thing that happened with the Apollo samples.

When they came back from the moon in the 1960s and 70s, some of the samples were put into long-term storage and have only been opened and people have only started analysing them in the last four or five years.

Analytical techniques we have now are hugely developed from the techniques that were available 50 years ago.

Asking questions and having the techniques that we haven't even thought of yet or haven't even invented.

Exactly.

Well, thank you to both of our planetary Sarahs.

And we still have Graham Lawton here in the Salford studio, a writer at New Scientist.

Hello again, Graham.

Hi.

Now, we asked you to troll through some of the science of the week.

It's been a busy week and you've hand-picked a few highlights for us, haven't you?

I have.

And we have to talk about artificial intelligence, don't we?

Well, I think we probably do this week.

Specifically, DeepSeek, this new AI from China that's really put the cat amongst the pigeons.

There's been so much talk about this.

Give us a kind of brief lowdown.

It's a large language model, very much like the ones that we're familiar with, but the thing that's different about it is that it performs at a level of those more familiar things, but on an absolute shoestring.

And it's been called AI's Sputnik Moment.

I think that's appropriate in some ways because what's happened is it's got to come out the blue and it's really burst the bubble of people who thought they were leading a technological race but turned out that they were blowing their own trumpets a bit too hard.

It's not technologically very different from what we already have but those large language models, how do they work?

They're essentially like scouring all of this information for patterns and then they use that to predict when you can ask them questions to predict the next thing that they'll say.

I'm glad you explained that

from that it can construct things that appear to be intelligent and knowledgeable answers.

You know, whether they are or not is up for debate.

So in technological terms, DeepSeek isn't anything particularly new, but from another perspective, it's hugely disruptive, and that's from the fact that it cost almost nothing to put together.

I mean, according to these unverified claims, it was 20 to 50 times cheaper than the AIs developed by like OpenAI, Google, Meta, the big names in that industry.

So DeepSeek claims to have spent just over $5 million

on training this AI, and that's like an absolute fraction of the hundreds of millions that the competitors have spent.

It uses significantly less computing power, and the training data was much smaller.

And what that kind of suggests is that those big companies have done too much.

They've put too much into their systems.

They didn't need to do that to get the same kind of results.

Now, I know there's a bit of a dispute over whether DeepSeek actually did what it said it did and maybe it used somebody else's training data.

But I think that it is a moment for AI to sort of sit back and think, okay, what are we doing wrong?

What have we done right?

I mean, there are things about this that are also really exciting from a science perspective.

For one thing, it's open source, which means that other people who are not involved in the project can sort of go in and look at the code and rummage around and change things and add things.

And that will probably stimulate some more research in this area.

And also, because it's so cheap, it opens AI up to researchers and students who'd love to be able to use these things but just can't afford the very top-end products that are coming out of the United States.

There's been some caution urged about deep-seat caution over downloading it, about what'll happen to your data, and also about misinformation.

I know some of our BBC colleagues asked DeepSeek, it's made by a Chinese company, they asked DeepSeek what happened in Tiananmen Square and it didn't answer.

And it was just an example of how censorship is perhaps kind of casting a shadow over how helpful and truthful that information that DeepSeek's giving you is.

Yeah, I mean, I think there is mistrust around it.

And it's all kind of plays into the story going around about TikTok in the United States and so on.

But I I think that using any of these things, you need to be cautious because as soon as, even with like with social media, as soon as you spill some of your data out into the world of technology, you've spilled it out there and that's where it's going to stay.

And you're kind of opening yourself up to all sorts of, well, God knows what.

We'll find out, won't we?

Now, we've been talking a lot about life on Earth this week, haven't we?

And you have a fascinating, rather strange story about mice.

Yeah, so this is reports coming out of China that researchers there have created mice that have two dads.

Oh.

So rather than a mother and a a father, they've got two fathers.

Now, this is quite a breakthrough in terms of stem cell biology, in terms of reproductive biology.

And it obviously raises the question of, well, if we can do it in mice,

can we do it in humans?

Is it possible that two men could have a child who is biologically both of theirs rather than using, they'd have to use a surrogate mother?

The answer to that is no.

Right.

Not yet.

Not yet.

Anyway, in theory, yes.

In practice, it's quite difficult.

So mice with two mothers are a well-known phenomenon.

They were created maybe 20 years ago, but mice with two fathers is technically much more difficult.

And there have been reports that it's been done in the

past few years, but this is the first time we've got confirmation.

Why was this such a challenge to have two male parents, to have two sperm and their biological information in one embryo?

Sperm and egg are what's called imprinted.

They carry certain patterns of gene expression.

And to make an embryo from two male cells, you have to replicate an egg cell's imprinting.

And the egg cell imprinting is much more complicated than a sperm cell imprinting.

Oh, I see.

So, you have to sort of switch the sperm into taking on the role of an egg, and that's genetically very tricky.

Yes, it's a huge technical challenge, which has finally been achieved.

Whole new ethical minefield there, I can see.

It is a huge ethical minefield, and that's one reason why this is not really applicable to humans, because we'd have to bypass some ethics that we consider at the moment to be kind of red lines that we that we wouldn't cross.

People who are either excited about this because they think, oh, I could have a child with my male partner, or people who are kind of opposed to it, both of them are going to be disappointed.

That solves that ethical quandary for now.

What else have you brought for us in your bag of stories this week, Graham?

Well, this is a kind of Anthony moment, really.

It's a nice story.

Well, it's good timing.

It's a nice story.

So, how often do you think unexpected scientific discoveries occur?

As in unplanned, not looked for, or hypothesized.

Exactly.

The kind of things that, well, Alexander Fleming discovering penicillin because he left his Petri dish by a window, those kinds of discoveries.

Maybe not quite so consequential as that, but...

I don't know, maybe a third of the time, a quarter of the time.

You'd think that, wouldn't you?

It's more like 70% of the time.

Wow.

So a study which came out of the University of Sussex in a journal called Research Policy, which is not a journal I would normally read.

Sorry, Research Policy.

Avid reader of research policy.

But the journal Nature picked this up and did a really nice story about it.

So they looked at 1.2 million biomedical publications and measured what they call the unexpectedness of the findings.

But they looked at these 1.2 million papers and found that almost three quarters of them contained unexpected results.

And how they worked that out was they looked at what the original grant proposal had said, which is where the scientists lay out what they're going to do.

And then they looked at the research papers that came out of there and they compared the two, using AI actually, as another application of AI in science.

And what they found was surprising to them and probably to everybody is that, as I said, 70% of those papers that came out of those research proposals found something that the scientists had not said they expected to find.

So you've squared the circle all the way back to AI, AI and surprises.

That's fascinating.

Thank you very much, Graeme.

It's been lovely to chat to you about a busy week in science.

My pleasure.

Well, surprisingly or unsurprisingly, because we do know how long we have for this programme, that is all we have time for this week.

So thank you so much to both of our planetary Sarahs, to Graham Lawton from New Scientists, and to all of our listeners.

Until Until next time, thanks for listening.

You've been listening to BBC Inside Science with me, Victoria Gill.

The producers were Sophie Ormiston, Ella Hubber, and Gerry Holt.

Technical production was by Kath McGee and Natalie Ladley.

The show was made in Cardiff by BBC Wales and West.

To discover more fascinating science content, head to bbc.co.uk, search for BBC Inside Science and follow the links to the Open University.

Until next week, thanks for listening and bye-bye.