Nature-based solutions in the fight against climate change | Thomas Crowther | TEDxLausanne

Summary

David DeRuwe shares his journey from struggling student to leading environmental scientist, emphasizing the power of embracing challenges. He discusses the importance of ecological engagement, particularly in the face of climate change, and introduces innovative solutions like the trillion tree campaign. DeRuwe highlights the potential of natural systems, such as forests and grasslands, to capture carbon and mitigate climate change, urging a combined approach of ecological restoration and emission reduction.

Takeaways

• 🌿 The speaker emphasizes the importance of embracing challenges, drawing a parallel between the difficulty of a game and the struggle in scientific research.
• 🎓 He shares a personal story of academic struggle and dyslexia, which led to a pivotal advice from a professor to treat ecology as a game, sparking a change in his approach.
• 🌳 The speaker is currently engaged in global-scale research on biodiversity, focusing on climate change as one of the greatest threats to it.
• 🔢 He highlights the staggering amount of carbon emissions, comparing 10 gigatons to the weight of 27,000 Empire State Buildings, to illustrate the scale of the problem.
• 🌍 The speaker discusses the role of natural systems in combating climate change, particularly the carbon cycle's ability to absorb CO2, exemplified by the emergence of leaves on trees.
• 🌲 He introduces the concept of global tree density and how new models, using machine learning and AI, have revealed there are over 3 trillion trees on Earth, not 400 billion as previously thought.
• 🌱 The potential of restoring ecosystems on degraded lands is presented as a significant carbon drawdown solution, with the possibility of adding another trillion trees.
• 🌟 The speaker addresses criticisms by advocating for a multifaceted approach that includes both emissions cuts and ecosystem restoration.
• 💰 He discusses the economic feasibility of large-scale ecosystem restoration, suggesting it could be achieved for as little as thirty cents per tree.
• 🌐 The speaker calls for global action, emphasizing that even partial achievements in ecosystem restoration can have a significant positive impact on climate change and biodiversity.

Q & A

What is the game 'frisball' mentioned in the script?

Frisball is a game where a group of people pass a ball and a frisbee around without using their hands, throwing the ball in the air and then the frisbee to the next person who catches the frisbee and then the ball.

Why did the speaker struggle during his university years?

The speaker struggled because he was dyslexic and found it hard to keep up with the required reading, which led to a lack of motivation. He was also obsessed with games, which he thought was a distraction from his studies.

What advice did the professor give to the speaker that changed his perspective?

The professor advised the speaker to make ecology his next game, embracing the challenge and enjoying the process, which would increase his chances of success and make the learning experience more enjoyable.

What is the speaker's current focus in the field of biodiversity?

The speaker is currently studying the impact of climate change on biodiversity at a global scale, focusing on one of the greatest threats to biodiversity.

How much carbon is emitted into the atmosphere annually according to the script?

According to the script, 10 gigatons of carbon are emitted into the atmosphere annually.

What is the significance of the number 300 gigatons mentioned in the script?

The number 300 gigatons represents the total amount of carbon that has been added to the atmosphere since the start of the Industrial Revolution, highlighting the scale of the problem that needs to be addressed.

How does the speaker describe the natural system's role in carbon capture?

The speaker describes the natural system, particularly trees and forests, as the most powerful system we have to date for capturing carbon, emphasizing the importance of effective management of these ecosystems.

What was the previous global estimate of the number of trees on Earth before the new model was developed?

Before the new model was developed, it was estimated that there were about 400 billion trees on Earth.

How many trees are there actually on Earth according to the new model?

The new model revealed that there are over 3 trillion trees on Earth.

What is the potential additional carbon storage if ecosystems are restored across all degraded lands?

If ecosystems are restored across all degraded lands, there could be an additional storage of 205 gigatons of carbon.

What are the criticisms mentioned in the script regarding the approach to climate change?

The criticisms mentioned are the need for emissions cuts, the importance of conserving existing forests, and the necessity to preserve and restore natural grasslands and savannas.

Outlines

00:00

🌿 Embracing the Challenge of Biodiversity and Climate Change

The speaker, an environmental scientist, shares a personal story about their journey from struggling with university studies to becoming deeply engaged in the study of biodiversity and climate change. They describe a game called 'frisball' that symbolizes the challenge of environmental science, where the goal is to keep a ball and a frisbee in the air without using hands. The game is hard, but the speaker finds it addictive because it reflects the difficulty and importance of their work. The speaker was inspired by a professor who suggested turning the study of ecology into a game, which led to a profound change in their approach to learning and research. Now, the speaker focuses on the global threat of climate change and the need to engage people in making a tangible impact. They discuss the challenge of understanding the scale of the problem and the importance of natural systems in capturing carbon emissions, emphasizing the role of trees in the carbon cycle.

05:01

🌳 The Power of Trees and the Trillion Tree Campaign

The speaker discusses the importance of understanding the physical possibilities of ecosystem restoration, particularly the role of trees in capturing carbon. They highlight the limitations of previous knowledge about global tree numbers and how new models using machine learning and artificial intelligence have revealed that there are over 3 trillion trees on Earth. This new understanding has led to the expansion of the UN's tree planting campaign from a billion to a trillion trees. The speaker explains how these models not only show current tree distribution but also potential areas for new tree growth. They emphasize the immediate and long-term benefits of tree planting, such as carbon sequestration and cloud formation that reflects sunlight and cools the planet. The speaker also addresses criticisms, acknowledging the need for emissions cuts and the importance of conserving existing forests and other ecosystems like grasslands and savannas.

10:04

🌱 Soil Carbon Sequestration and Ecosystem Restoration

The speaker continues the discussion on climate solutions by introducing the potential of soil carbon sequestration, particularly in high latitude areas where cold conditions trap carbon. They mention a new generation of models based on millions of soil samples that reveal over 1,500 gigatons of carbon stored in the soil. The speaker argues for the restoration of soils across the globe to capture an additional 116 gigatons of carbon. They emphasize the importance of preserving and restoring not only forests but also grasslands, shrublands, and wetlands, each of which has a significant role in carbon capture. The speaker stresses the need for ecological and social responsibility in restoration projects, ensuring that they are done in a way that supports local communities and does not disrupt existing land uses. They highlight the economic feasibility of such projects, suggesting that restoring a trillion trees could be achieved for as little as 300 billion dollars.

15:08

💪 Global Action and Overcoming Negative Thinking on Climate Change

In the final paragraph, the speaker calls for global action on climate change, emphasizing that every individual has the power to make a difference. They suggest three ways for individuals to get involved: by restoring ecosystems themselves, donating to restoration projects, or investing in organizations with positive environmental impacts. The speaker acknowledges the criticism that the scale of the task is too large to be accomplished but argues that even achieving a small percentage of the goals would have significant benefits. They encourage overcoming negative thinking and embracing the challenge of climate change, drawing inspiration from their mentor's advice to enjoy the process of working towards solutions. The speaker concludes by expressing hope that the pessimists won't hinder the efforts of those already working on climate solutions and by highlighting the unique opportunity of the current society to make a positive impact on the world.

Keywords

💡Biodiversity

Biodiversity refers to the variety of life on Earth, including the variety within species, between species, and of ecosystems. In the video, the speaker is passionate about biodiversity and its study, which is central to understanding how life arose and diversified on our planet. The speaker's initial struggle with keeping up with the study of biodiversity due to dyslexia and the overwhelming nature of the subject is a key part of their personal journey.

💡Climate Change

Climate change is a long-term shift in global or regional climate patterns. The video discusses climate change as one of the greatest threats to biodiversity and emphasizes the need for action to mitigate its effects. The speaker uses the example of carbon emissions and their impact on the atmosphere to illustrate the scale of the problem and the urgency for solutions.

💡Carbon Cycle

The carbon cycle is the biogeochemical process by which carbon is cycled through the Earth's atmosphere, oceans, soil, plants, and animals. In the video, the speaker highlights the importance of the carbon cycle, particularly the role of trees in absorbing carbon dioxide and the potential for reforestation to help combat climate change.

💡Ecological Fluxes

Ecological fluxes are the flows of energy and matter between living organisms and their environment. The video mentions ecological fluxes in the context of the natural carbon cycle, where processes like the emergence of leaves on trees help to balance the concentration of carbon dioxide in the atmosphere. These fluxes are critical for maintaining the health of ecosystems and the planet.

💡Reforestation

Reforestation is the process of replanting an area with trees that has been deforested. The speaker discusses reforestation as a powerful solution to climate change, emphasizing the potential for capturing carbon and the need for a new approach that includes both technological solutions and natural systems.

💡Machine Learning

Machine learning is a subset of artificial intelligence that allows computers to learn from data without being explicitly programmed. In the video, the speaker describes how machine learning and artificial intelligence are used to analyze data from millions of tree observations, leading to a better understanding of global tree density and the potential for reforestation.

💡Degraded Lands

Degraded lands are areas where the natural environment has been damaged or destroyed, often due to human activities. The video talks about the potential of restoring degraded lands to support more trees, which could help in capturing carbon and mitigating climate change. The speaker highlights the importance of identifying and utilizing these lands for reforestation efforts.

💡Carbon Drawdown

Carbon drawdown refers to the process of removing carbon dioxide from the atmosphere and storing it in long-term reservoirs, such as forests or soils. The video emphasizes the concept of carbon drawdown as a critical strategy in the fight against climate change, with the speaker presenting data on the potential of forests and soils to capture significant amounts of carbon.

💡Social Responsibility

Social responsibility involves considering the impact of actions on society and ensuring that they are equitable and sustainable. In the context of the video, the speaker stresses the importance of engaging local communities in restoration projects to ensure that they are socially responsible and sustainable, providing benefits to the communities while also addressing climate change.

💡Ecosystem Services

Ecosystem services are the benefits that humans obtain from ecosystems, such as food, water, and climate regulation. The video discusses the importance of ecosystem services in the context of restoration projects, highlighting how these projects can provide socioeconomic benefits to local communities while also contributing to climate change mitigation.

💡Negative Thinking

Negative thinking refers to a mindset characterized by pessimism and a tendency to focus on the potential failure or negative outcomes of a situation. The speaker in the video challenges this mindset, arguing that it is an obstacle to taking action on climate change. Instead, the speaker advocates for embracing challenges and focusing on the potential for positive change.

Highlights

Embracing challenges is key to success and enjoyment.

Frisball, a game involving throwing a ball and a frisbee, is used as a metaphor for tackling hard tasks.

The speaker's dyslexia and love for games initially hindered his academic progress.

A professor's advice to make ecology a game led to a profound change in the speaker's approach.

Biodiversity study at a global scale is the speaker's current focus.

Climate change is one of the greatest threats to biodiversity.

The atmosphere's vulnerability is compared to the width of rubber on a balloon.

10 gigatons of carbon emissions annually is a staggering number.

300 gigatons of carbon burden increase since the Industrial Revolution.

Natural systems are the most powerful tools we have to combat climate change.

The carbon cycle is significantly affected by the emergence of leaves on trees.

Ecosystem management is undervalued in climate change solutions.

Satellites have limitations in assessing global forest cover.

There are over 3 trillion trees on Earth, not 400 billion as previously thought.

Restoring ecosystems can potentially store 205 gigatons of carbon.

Restoration projects have gained significant funding and momentum.

Criticism highlights the need for a multifaceted approach to climate change solutions.

Conservation of existing forests is as critical as expanding new ones.

Grasslands and savannas are important ecosystems for carbon storage.

Soil carbon storage potential is immense and can be unlocked through restoration.

Restoration projects must be ecologically and socially responsible.

The cost of restoring one trillion trees is estimated to be as low as 300 billion dollars.

Individuals can contribute to climate solutions through direct action or investment.

Negative thinking is a barrier to achieving climate change goals.

Embracing the challenge of climate change is essential for global action.

Transcripts

Transcriber: AFRAA ALZOUBI Reviewer: David DeRuwe

Life ...

it's all about embracing the challenge.

Everyday, our lab brings together

some of the world's leading environmental scientists,

bringing together all that brain power

to desperately try to figure out

how to get this ball round a group of people

without using our hands.

It's so good; you hold a ball and a frisbee,

you throw the ball in the air,

throw the frisbee to the next person

who catches the frisbee and then the ball

without ever touching their hands.

This challenge, frisball, is unbelievably addictive

for the very simple reason that it's really, really hard.

The failures can be catastrophic.

But when you get lost in that game and it just takes you,

it's unbelievable how those failures just pale

in comparison to the true glory of success.

(Laughter)

I always thought this obsession with games

is why I struggled in the university.

When I was kicked out of class at the end of my first year,

I thought it was the end of my degree.

300 people, I had to walk out in front of.

It was devastating,

but the professor took me aside and asked me,

"Why bother? Why bother with ecology if you're not even going to try?"

To which I explained, "I've always been obsessed with biodiversity.

How life arose on this planet remains the greatest mystery,

let alone how it diversified across the globe.

But I simply cannot keep up.

It's really hard to stay motivated when you can't keep up,

and on top of that, I'm dyslexic,

and so I failed to keep up with the boring reading,

and, instead, preferred to play games with my friends."

And he gave me the simplest bit of advice ever.

He just said, "If you truly enjoy it, why not make ecology your next game?"

And I know it sounds so simple, but it had the most profound impact on me.

He said, "You don't need to try harder, you certainly don't need to be smarter,

but if you embrace the challenge,

not only are you way more likely to succeed,

but even if you don't,

Who actually cares? - you've been having a good time,

and that's the point of all this in the long run anyway."

Now, that simple advice had the most profound impact on me,

and eight years later, I'm still studying biodiversity,

this time, at a global scale.

And in fact, I'm studying one of the greatest threats

facing biodiversity of all time in climate change,

this depressing topic

that every single person in this room knows plenty about,

so don't worry, I won't bog you down with the depressing details.

We all know how threatening it is to us and our future generations,

but the real challenge is figuring out how that we can get engaged,

how can we make tangible impact

to slow the rate of this devastating threat.

Because the atmosphere that we're trying to protect

is incredibly thin and vulnerable -

it's like analogous to the width of the rubber on a balloon.

And every year, we emit 10 gigatons of carbon into that space.

I know a gigaton is a weird number,

but essentially, it's a billion tons of carbon.

So 10 gigatons is like 27,000 Empire State Buildings.

And some of it goes into the land, and some of it goes into the oceans,

but a large chunk of it remains in the atmosphere,

and it's building up year on, year out,

to the extent that we've increased the burden by about 300 gigatons

since the start of the Industrial Revolution.

Now, I'm a scientist, so I love numbers,

and I'm going to throw big nonsense numbers at you,

but if I could get you to remember at least one number,

it's that 300 gigatons because that -

that's the scale of the problem we need to address.

So of course, we urgently need technological solutions

to stop those 10 gigatons every year.

We need to prevent emissions,

but if we want to capture the 300 gigatons that already exist,

we're going to need an immensely powerful system,

and the most powerful system we've got to date is this:

the natural system.

This is a beautiful NASA simulation of the carbon cycle,

showing high concentrations of carbon dioxide,

indicated by red, at the beginning of the year,

but as we kick on into spring, and then summer,

we'll see these concentrations fade,

and that's caused by one really simple thing:

it's just the emergence of leaves on the trees.

This simple ecological process transforms the carbon cycle every year,

and it's one of the several massive ecological fluxes

that entirely balance one another out.

Given the massive scale of this system,

managing it effectively

has to be one of our brightest options in the fight against climate change.

But it's also the nonsense one,

we've all heard it before,

the happy-clappy solution, "Plant a tree, save the world,"

we've all heard it before,

but it's clearly not worked, because otherwise we'd be fine.

But the real reason is

we've not been able to get engaged.

Because it's not a tangible and scientific solution,

for the very simple fact

that we have no idea what's physically possible.

Until we know what we can achieve,

who's going to waste their time and energy restoring ecosystems

if you don't know what the impact will be.

If we look at the top climate change solutions -

Project Drawdown is a brilliant organization listing them -

at the top of the list,

with the potential to save 24 gigatons,

is effective refrigeration management.

But if you look down the list for global ecosystem management,

you won't even find it

because ecosystems, we have no idea of their global potential.

So they're broken up into smaller parts and listed far below the top solutions.

Again, who of us is going to spend our valuable time and energy in this,

unless we know what we can actually achieve.

Well, the real challenge is that the Earth's massive.

It's really difficult to get a handle on that global information.

So we've used satellites very well for the last few decades,

which have great global coverage,

but they can't see below the canopy surface.

So until recently, we thought there was about 400 billion trees on the planet.

And that was the basis of the UN's billion tree campaign:

to plant a billion trees to save the world.

But we knew we needed a new generation of model,

a model built from millions of locations

where people have stood on the ground counting trees

and estimating how big those trees are

and also which species they are.

And once you've got all that information,

you've got insights into the forest's structure,

and by pairing all those millions of data points together,

using machine learning and artificial intelligence,

we can now start to fill in the gaps, and see the patterns in tree density,

and how they vary across gradients of temperature

and moisture and soil characteristics

to generate the first quantitative understanding of global tree density,

revealing, quite simply, that there are over 3 trillion trees on our planet.

Again, I realize it's hard to understand what a trillion is,

but essentially, it's more than we previously thought,

and that simple piece of information

was enough to change the billion tree campaign

into the trillion tree campaign.

So now we're restoring a trillion trees, and it's having great impact.

Because we know the size of those trees,

we also know that they store about 450 gigatons of carbon.

That's the basis we're working with.

But these models don't just tell us where trees are now.

By characterizing the environment that can support trees,

they also help us to see where trees can exist on the planet,

showing that there's room for vastly more than we currently have.

But obviously, much of this land is currently covered by forests,

and a large proportion of it, we need for urban land and agricultural land

that we need to support a growing human population.

But when we remove those lands,

we are left with something incredible.

These are the 0.9 billion hectares of degraded lands,

places where trees could naturally exist,

but they don't, even though we're not using them extensively.

If we were to restore ecosystems across all of those lands,

there would be an additional trillion trees in that area,

and they would store a staggering 205 gigatons of carbon.

Now again, there's a lot of uncertainty in that number -

they could be slightly higher or lower -

but the scale of this,

when you compare it to the 300 gigatons I mentioned earlier,

we can all see

that there is a vastly and immensely powerful carbon drawdown solution

in the world's forests.

Obviously, it would take over a hundred years

to accumulate all of that carbon,

but as soon as those trees are in the ground,

not only are they sucking up carbon, they're also producing clouds,

and those clouds reflect a lot of the sun's energy away,

cooling the planet with an immediate effect.

So when we announced this information less than two months ago,

something just clicked, and it went absolutely viral.

There was not an international media organization

that didn't cover this extensively.

It was like the public finally just saw an option for us to get engaged,

and it was followed by an unbelievable spike

in funding for restoration projects.

And we saw projects starting up all over the world,

and these are just the few that our lab is directly connected to.

We're aware of thousands of others

that are emerging to restore ecosystems to capture carbon.

But it also introduced us to some of the wonders of social media,

which was a terrifying insight.

We had an absolute insanity of messages,

but when you sift through those messages,

there are some really important and valuable themes.

The first criticism,

"This is so stupid.

We can't just plant trees everywhere, we need emissions cuts."

While I don't entirely love the introduction to it,

this is absolutely correct.

I can't argue with that.

Of course, everybody must know

that we need technological and system-level changes

to prevent emissions.

But that has to be done in combination with powerful carbon drawdown.

Climate change is way too big for us to be squabbling over solutions -

we need all of them right now.

The second criticism,

"No! We need to conserve existing forests."

Once again, it's very hard to disagree because this is absolutely correct!

Of course, increasing the global forest cover

wouldn't make any sense

if we just gained new forests at the expense of the old ones.

Preserving those existing forests is central to our entire goal.

Of course, it's absolutely critical,

so they must be done in combination.

And the third criticism - you can see a trend now -

is we need to preserve and restore natural grasslands and savannas,

and again, for fear of repeating myself,

this is abundantly correct.

These ecosystems are immensely important,

and that was part of the reason for us doing the study in the first place,

so that we could identify where trees should go and where they shouldn't.

Because those ecosystems are really key as well.

They store huge amounts of biodiversity, and their carbon is amazing too,

but it's not stored in the vegetation.

It's actually stored in the soil below our feet.

So we've been building a new generation of models now.

Instead of basing them on observations of trees,

they're based on millions of soil samples, collected all across the globe.

And again, using the same artificial intelligence and machine learning,

we can start to see the patterns,

revealing that there is over 1,500 gigatons of carbon

in the soil below our feet,

with the majority of it existing in the high latitude areas,

where cold conditions trap up carbon in the soil.

And the amazing thing

is that if we restored those soils across the globe,

we could capture another 116 gigatons of carbon.

That's the second insanely powerful carbon drawdown solution

that I've introduced to you,

and that's just in the soil below our feet.

And this expands across all ecosystems.

Where forests are now,

just conserving and preserving them could capture 30% of that.

But grasslands and shrublands cover an even larger expanse,

and they could capture a staggering 41% of that potential

if we just restore them effectively.

And the nice thing about them

is that they don't come at the expense of any other land use type.

So you could have your agriculture

at the same time as preserving and capturing more and more carbon.

And actually, the most efficient of all those ecosystems

are the wetlands and peatlands

which would cover less than 5% of the Earth's surface

and could capture about 30% of that amount.

So when all in combination, we can see that these ecosystems

have an overwhelming potential to capture this 300 gigatons.

This powerful carbon drawdown solution is not just immense,

but it's also one that can engage every single one of us

and must be done in combination with cuts to greenhouse gas emissions.

But of course, they have to be done ecologically responsibly.

Too many times, restoration projects fail

because trees are restored in the wrong soils

or in ecosystems

without a microbial community that can support them.

So we spend all of our time and energy generating maps,

maps that can show land managers how to manage those ecosystems right,

so they can zoom into their area of interest

and say not only how many trees go there or which species of trees should go there,

but you can even see what the soil microbial community is like,

to see if they support trees.

And you can even calculate

where the forests would have a warming or a cooling impact

in different parts of the globe

to really understand the ecological consequences of those actions.

And even more importantly than that

is that these projects have to be socially responsible.

Too many times, restoration projects come and they buy up an area of land,

excluding people from that land.

Now that land

is those people's livelihoods.

Not only is that socially irresponsible, but it's also unsustainable

because those people will come back and cut down that forest

and use it for their livelihoods subsequently.

Restoration has to be done in combination with local communities,

so all funding coming towards restoration projects

can be funneled through that community,

so they become connected to that project.

On top of that, they can benefit from the thousands of ecosystem services

like food and medicine, and clean air and water

that bring huge socioeconomic benefits when done correctly.

All of those projects, those little dots that I showed you earlier, are doing this,

working in combination with the local communities

to restore ecosystems around the world,

and they're having incredible social and economic consequences.

And the best of them are doing so for as little as thirty cents a tree.

And so this means, if we were to restore our one trillion trees,

if we were to maximize efficiency,

we could do so for as little as 300 billion dollars.

That is nothing

compared to the trillions of dollars we spend every year

as a result of climate change.

So now we genuinely do have a climate solution

that can engage every single one of us through simple and tangible actions

that have a positive impact,

either by restoring ecosystems yourselves,

and you can look at the maps to see exactly where and how,

or simply donate.

Click on one these dots to donate

to one of the incredible restoration projects

that are doing unbelievable work on our behalf,

or finally, just invest your money wisely.

Whether you're spending it or investing it,

focus on the organizations that have a positive environmental impact,

and we can have tangible impact on climate change.

There's 8 billion of us on this planet.

That gives us an unprecedented power for global action,

but until now,

climate action has always been about giving up the things we love,

and while those commitments are incredibly important

for cutting greenhouse gas emissions,

we now also have positive actions that we can take,

which make us feel good, and get us involved in the fight.

Which brings me to the final criticism,

"This all sounds fine, but it's just naive.

We'll never restore the entire globe."

Now this criticism may also be correct, but it's also entirely irrelevant.

Because this thinking doesn't help anything.

Ultimately,

this is just an excuse to do nothing,

"If we can't achieve 100%, ah, let's not bother."

This is the kind of thinking that got us in this place.

If we achieve even 5% of our goals,

the impacts for biodiversity and climate change would be incredible,

and I can promise you, we're going to exceed those efforts

with the thousands of people restoring ecosystems around the world.

I just hope the people saying, "It can't be done"

don't interrupt the incredible people that are already doing it.

Overcoming this negative thinking, this depression around climate change,

I think is one of our greatest remaining challenges to get us all engaged.

And to do this, I draw on the words

of that brilliant supervisor, Dr. Hefin Jones,

who said, "Just embrace the challenge.

Not only are we more likely to succeed,

but we'll all literally be enjoying the process."

We may be the first society facing the real threat of climate change,

but that necessarily means we're the first society

that has a chance to save the world against it.

Thank you very much.

(Applause)