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  • Transcriber: Ivana Korom Reviewer: Krystian Aparta

  • I'm here to talk about climate change,

  • but I'm not really an environmentalist.

  • In fact, I've never really thought of myself as a nature person.

  • I have never gone camping, never gone hiking,

  • never even owned a pet.

  • I've lived my whole life in cities,

  • actually just one city.

  • And while I like to take trips to visit nature,

  • I always thought it was something that was happening elsewhere,

  • far away,

  • with all of modern life a fortress against its forces.

  • In other words,

  • like just about everybody I knew,

  • I lived my life complacent

  • and deluded

  • about the threat from global warming.

  • Which I took to be happening slowly,

  • happening at a distance

  • and representing only a modest threat to the way that I lived.

  • In each of these ways,

  • I was very, very wrong.

  • Now most people, if they were telling you about climate change,

  • will tell you a story about the future.

  • If I was doing that, I would say,

  • "According to the UN, if we don't change course,

  • by the end of the century,

  • we're likely to get about four degrees Celsius of warming."

  • That would mean, some scientists believe,

  • twice as much war,

  • half as much food,

  • a global GDP possibly 20 percent smaller than it would be without climate change.

  • That's an impact that's deeper than the Great Depression,

  • and it would be permanent.

  • But the impacts are actually happening a lot faster than 2100.

  • By just 2050, it's estimated,

  • many of the biggest cities in South Asia and the Middle East

  • will be almost literally unlivably hot in summer.

  • These are cities that today are home to 10, 12, 15 million people.

  • And in just three decades,

  • you wouldn't be able to walk around outside in them

  • without risking heatstroke or possibly death.

  • The planet is now 1.1 degrees Celsius warmer

  • than it was before industrialization.

  • That may not sound like a lot,

  • but it actually puts us entirely outside the window of temperatures

  • that enclose all of human history.

  • That means that everything we have ever known as a species,

  • the evolution of the human animal,

  • the development of agriculture,

  • the development of rudimentary civilization

  • and modern civilization and industrial civilization,

  • everything we know about ourselves as biological creatures,

  • as social creatures, as political creatures,

  • all of it is the result of climate conditions

  • we have already left behind.

  • It's like we've landed on an entirely different planet,

  • with an entirely different climate.

  • And we now have to figure out

  • what of the civilization that we've brought with us

  • can endure these new conditions

  • and what can't.

  • And things will get worse from here.

  • Now for a very long time,

  • we were told that climate change was a slow saga.

  • It started with the industrial revolution,

  • and it had fallen to us

  • to clean up the mess left by our grandparents

  • so our grandchildren wouldn't be dealing with the results.

  • It was a story of centuries.

  • In fact, half of all of the emissions

  • that have ever been produced from the burning of fossil fuels

  • in the entire history of humanity

  • have been produced in just the last 30 years.

  • That's since Al Gore published his first book on warming.

  • It's since the UN established its IPCC climate change body.

  • We've done more damage since then

  • than in all the centuries, all the millennia before.

  • Now I'm 37 years old,

  • which means my life contains this entire story.

  • When I was born, the planet's climate seemed stable.

  • Today,

  • we are on the brink of catastrophe.

  • The climate crisis is not the legacy of our ancestors.

  • It is the work of a single generation.

  • Ours.

  • This may all sound like bad news.

  • Which it is, really bad news.

  • But it also contains, I think,

  • some good news, at least relatively speaking.

  • These impacts are terrifyingly large.

  • But they are also, I think, exhilarating.

  • Because they are ultimately a reflection

  • of how much power we have over the climate.

  • If we get to those hellish scenarios,

  • it will be because we have made them happen,

  • because we have chosen to make them happen.

  • Which means we can choose to make other scenarios happen, too.

  • Now that may seem too rosy to believe

  • and the political obstacles are in fact enormous.

  • But it is a simple fact --

  • the main driver of global warming is human action:

  • How much carbon we put into the atmosphere.

  • Our hands are on those levers.

  • And we can write the story of the planet's climate future ourselves.

  • Not just can -- but are.

  • Since inaction is a kind of action,

  • we'll be writing that story ourselves whether we like it or not.

  • This is not just any story,

  • all of us holding the future of the planet in our hands.

  • It's the kind of story we used to recognize only in mythology

  • and theology.

  • A single generation

  • that has brought the future of humanity into doubt

  • now tasked with securing a new future.

  • So what would that look like?

  • It could mean solar arrays barnacling the planet,

  • really everywhere you looked.

  • It could mean if we developed better technology,

  • we wouldn't even need to deploy them that broadly,

  • because it's been estimated that just a sliver of the Sahara desert

  • absorbs enough solar power to provide all the world's energy needs.

  • But we'd probably need a new electric grid,

  • one that doesn't lose two-thirds of its power to waste heat,

  • as is today the case in the US.

  • We could use some more nuclear power, perhaps,

  • although it would have to be an entirely different kind of nuclear power,

  • because today's technology simply isn't cost-competitive

  • with renewable energy whose costs are falling so rapidly.

  • We'd need a new kind of plane,

  • because I don't think it's particularly practical

  • to ask the entire world to give up on air travel,

  • especially as so much of the global South

  • is, for the very first time, able to afford it.

  • We need planes that won't produce carbon.

  • We need a new kind of agriculture.

  • Because we probably can't ask people to entirely give up on meat and go vegan,

  • it would mean a new way of raising beef.

  • Or perhaps an old way,

  • since we already know that traditional pasturing practices

  • can turn cattle farms

  • from what are called carbon sources, which produce CO2,

  • into carbon sinks, which absorb them.

  • If you prefer a techno solution,

  • maybe we can grow some of that mean in the lab.

  • Probably, we could also feed some real cattle seaweed,

  • because that cuts their methane emissions by as much as 95 or 99 percent.

  • Probably, we'd have to do all of these things,

  • because as with every aspect of this puzzle,

  • the problem is simply too vast and complicated

  • to solve in any single silver-bullet way.

  • And no matter how many solutions we deploy,

  • we probably won't be able to decarbonize in time.

  • That's the terrifying math that we face.

  • We won't be able to beat climate change,

  • only live with it and limit it.

  • And that means we'd probably need

  • some amount of what are called negative emissions,

  • which take carbon out of the atmosphere as well.

  • Billions of new trees, maybe trillions of new trees.

  • And whole plantations of carbon-capture machines.

  • Perhaps an industry twice or four times the size

  • of today's oil and gas business

  • to undo the damage that was done by those businesses in past decades.

  • We would need a new kind of infrastructure,

  • poured by a different kind of cement,

  • because today, if cement were a country,

  • it would be the world's third biggest emitter.

  • And China is pouring as much cement every three years

  • as the US poured in the entire 20th century.

  • We would need to build seawalls and levees

  • to protect those people living on the coast,

  • many of whom are too poor to build them today,

  • which is why it must mean an end to a narrowly nationalistic geopolitics

  • that allows us to define the suffering of those living elsewhere in the world

  • as insignificant,

  • when we even acknowledge it.

  • This better future won't be easy.

  • But the only obstacles are human ones.

  • That may not be much of a comfort,

  • if you know what I know about human brutality and indifference,

  • but I promise you, it is better than the alternative.

  • Science isn't stopping us from taking action,

  • and neither is technology.

  • We have the tools we need today to begin.

  • Of course, we also have the tools we need to end global poverty,

  • epidemic disease

  • and the abuse of women as well.

  • Which is why more than new tools, we need a new politics,

  • a way of overcoming all those human obstacles --

  • our culture, our economics,

  • our status quo bias,

  • our disinterest in taking seriously anything that really scares us.

  • Our shortsightedness.

  • Our sense of self-interest.

  • And the selfishness of the world's rich and powerful

  • who have the least incentive to change anything.

  • Now, they will suffer too,

  • but not as much as those with the least,

  • who have done the least to produce warming

  • and have benefited the least

  • from the processes that have brought us to this crisis point

  • but will be burdened most in the decades ahead.

  • A new politics

  • would make the matter of managing that burden,

  • where it falls and how heavily,

  • the top priority of our time.

  • No matter what we do, climate change will transform modern life.

  • Some amount of warming is already baked in and is inevitable,

  • which means probably some amount of additional suffering is, too.

  • And even if we take dramatic action

  • and avoid some of these truly terrifying worst-case scenarios,

  • it would mean living on an entirely different planet.

  • With a new politics, a new economics,

  • a new relationship to technology

  • and a new relationship to nature --

  • a whole new world.

  • But a relatively livable one.

  • Relatively prosperous.

  • And green.

  • Why not choose that one?

  • Thank you.

  • (Applause)

Transcriber: Ivana Korom Reviewer: Krystian Aparta

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地球の気候の未来を変えるには? (How we could change the planet's climate future | David Wallace-Wells)

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    林宜悉 に公開 2021 年 01 月 14 日
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