Can seaweed help curb global warming? | Tim Flannery

譯者: Lilian Chiu 審譯者: Melody Tang

Oh, there's a lot of it.

喔，有好多。

This is seaweed.

這是海草。

它是...它是很不起眼的東西。

It's pretty humble stuff.

But it does have some remarkable qualities.

但它也有著很驚人的特質。

For one, it grows really fast.

比如，它成長的速度非常快。

So the carbon that is part of that seaweed,

所以，幾週前，

本來還屬於海草一部分的碳，

just a few weeks ago,

was floating in the atmosphere as atmospheric CO2,

已經飄入空氣中， 成為大氣二氧化碳，

driving all the adverse consequences of climate change.

促成各種有害的氣候變遷後果。

For the moment, it's locked safely away in the seaweed,

目前，它還被安全地關在海草中，

but when that seaweed rots --

但當海草腐爛時——

and by the smell of it, it's not far away --

根據聞起來的味道， 也應該快腐爛了——

when it rots, that CO2 will be released back to the atmosphere.

當海草腐爛時，二氧化碳 就會被釋放回到大氣中。

Wouldn't it be fantastic if we could find a way

大家應該都非常希望， 我們能夠找到一種方法，

of keeping that CO2 locked up long-term,

將二氧化碳長期關在海草中，

and thereby significantly contributing to solving the climate problem?

因而對解決氣候問題 有顯著的貢獻吧？

What I'm talking about here is drawdown.

我在這裡要談的是減量。

It's now become the other half of the climate challenge.

它現在已經變成 氣候挑戰的另一半了。

And that's because we have delayed so long,

那是因為在處理氣候變遷上，

我們已拖延了太久了，

in terms of addressing climate change,

that we now have to do two very big and very difficult things at once.

造成我們現在一次要面對 兩件非常非常困難的大事。

We have to cut our emissions and clean our energy supply

我們得要削減排放， 以及使能量供應更乾淨，

at the same time that we draw significant volumes

同時，我們也得要除去 大氣中大量的二氧化碳。

of carbon dioxide out of the atmosphere.

If we don't do that, about 25 percent of the CO2 we put in the air

如果我們不這麼做，我們排放到 大氣中的二氧化碳大約有 25%

will remain there, by human standards, forever.

會留在大氣中，以人類標準來說， 會持續到永遠。

So we have to act.

所以我們得馬上行動。

This is really a new phase in addressing the climate crisis

現在是處理氣候危機的一個新階段，

and it demands new thinking.

需要新思維。

So, ideas like carbon offsets really don't make sense

所以，「碳補償」這種想法

在現代是說不通的。

in the modern era.

You know, when you offset something,

當你要做補償時，你會說：

you say, "I'll permit myself to put some greenhouse gas into the atmosphere,

「我容許我自己放 一些溫室氣體到大氣中，

but then I'll offset it by drawing it down."

然後我會減量做為補償。」

When you've got to both cut your emissions

當你同時要削減你的排放，

and draw down CO2,

和減少既有二氧化碳時，

that thinking doesn't make sense anymore.

那種思維就不再合理了。

And when we're talking about drawdown,

當我們談減量時，

we're talking about putting large volumes of greenhouses gases, particularly CO2,

我們談的是將非常大量的 溫室氣體，特別是二氧化碳，

out of circulation.

從大氣循環中除去。

And to do that, we need a carbon price.

若要做到這一點，就需要碳價。

We need a significant price that we'll pay for that service

針對這個讓大家受益的服務，

that we'll all benefit from.

我們需要訂高價。

We've made almost no progress so far

在另一半的氣候挑戰上，

with the second half of the climate challenge.

我們幾乎沒有進展。

It's not on most people's radar.

大部分人沒有意識到它。

And, you know, I must say, at times, I hear people saying,

而且，我必須說， 有時，我聽見人們說：

"I've lost hope that we can do anything about the climate crisis."

「我失去希望了，我不認為 我們能解決氣候危機。」

And look, I've had my sleepless nights too, I can tell you.

我可以告訴各位， 我也有睡不著的夜晚。

But I'm here today as an ambassador for this humble weed, seaweed.

但，今天我是代表 這個不起眼的海草來到這裡。

I think it has the potential

我真心認為它有潛力

to be a big part of addressing the challenge of climate change

在處理氣候變遷的挑戰上， 及在我們的未來中，

and a big part of our future.

扮演一個很重要的角色。

Now, what the scientists are telling us we need to do over the next 80-odd years

科學家告訴我們，在這世紀結束前 剩下這八十多年間，

to the end of this century,

我們必須要做的是

is to cut our greenhouse gas emissions

每年減少 3% 削減溫室氣體排放，

by three percent every year,

每年減少 3% 削減溫室氣體排放。

and draw three gigatons of CO2 out of the atmosphere every year.

另外，每年也要從大氣中移除 三十億噸的二氧化碳。

Those numbers are so large that they baffle us.

這些數字太大了， 讓我們覺得不知所措。

But that's what the scientists tell us we need to do.

但這就是科學家說我們得要做的。

I really hate showing this graph,

我真的很不想放出這張圖，

but I'm sorry, I have to do it.

但，很抱歉，我必須這麼做。

It is very eloquent in terms of telling the story

這張圖非常有說服力地說出了

of my personal failure

我個人失敗的故事，

in terms of all the advocacy I've done in climate change work

說明我在氣候變遷工作上 做的所有倡導都失敗了，

and in fact, our collective failure to address climate change.

事實上，我們大家在處理 氣候變遷上都失敗了。

You can see our trajectory there

在這裡可以看到我們的軌道，

in terms of warming and greenhouse gas concentrations.

它代表的是暖化及溫室氣體濃度。

You can see all of the great scientific announcements that we've made,

在圖上可以看到我們過去 所有的重大科學宣佈，

saying how much danger we face with climate change.

指出我們面臨的 氣候變遷有多危險。

You can see the political meetings.

各位可以看到政治會議。

None of it has changed the trajectory.

以上這些都沒能讓軌道改變。

And this is why we need new thinking,

這就是為什麼我們需要新思維。

we need a new approach.

我們需要新方法。

So how might we go about drawing down greenhouse gases at a large scale?

所以，我們要如何大規模地 將溫室氣體減量？

There's really only two ways of doing it,

其實只有兩種方式，

and I've done a very deep dive into drawdown.

我對於減量已經做過 很深入的研究。

And I'll preempt my --

讓我先——

And I would say this stuff comes up smelling like roses at the end of the day.

我認為，最終它是真的很可行的。

It does, it's one of the best options,

它確實是最好的選項之一，

but there are many, many possibilities.

但，還有很多很多的可能性。

There are chemical pathways and biological pathways.

有化學途徑，有生物途徑。

So two ways, really, of getting the job done.

所以，有兩個方法可以搞定。

The biological pathways are fantastic

生物途徑很棒，

because the energy source that's needed to drive them, the sun,

因為這個途徑需要用的能量來源

is effectively free.

來自太陽，是免費的。

We use the sun to drive photosynthesis in plants,

我們用太陽來促進 植物的光合作用，

break apart that CO2 and capture the carbon.

來分解二氧化碳， 以及捕捉分解出的碳。

There are also chemical pathways.

另一個是化學途徑。

They sound ominous, but actually, they're not bad at all.

這個途徑聽起來有威脅性， 但其實一點也不。

The difficulty they face is that we have to actually pay

用這個途徑的困難之處在於

for the energy that's required to do the job

它們需要用的能源是要花錢的，

or pay to facilitate that energy.

或促成這種能源產生是要花錢的。

Direct air capture is a great example of a chemical pathway,

化學途徑有個很好的例子： 「直接空氣捕獲」，

and people are using that right now to take CO2 out of the atmosphere

現在就有人用它來除去 大氣中的二氧化碳，

and manufacture biofuels or manufacture plastics.

用來製造生物燃料或製造塑膠。

Great progress is being made,

目前已有很大的進步，

but it will be many decades

但仍然要數十年，

before those chemical pathways are drawing down a gigaton of CO2 a year.

那些化學途徑才能做到 每年減少十億噸二氧化碳。

The biological pathways offer us a lot more hope, I think,

我認為，短期來看，

生物途徑給我們更大的希望。

in the short term.

各位可能都聽過植樹造林、種樹，

You've probably heard about reforestation, planting trees,

as a solution to the climate problem.

作為解決氣候問題的方法之一。

You know, it's a fair question:

我來問一個合理的問題：

Can we plant our way out of this problem by using trees?

我們可以用樹木 把這個問題給「種」掉嗎？

I'm skeptical about that for a number of reasons.

我抱持懷疑，原因有好幾個。

One is just the scale of the problem.

第一就是這個問題的嚴重性。

All trees start as seeds, little tiny things,

所有的樹木一開始 都是種子，非常小的東西。

and it's many decades before they've reached

要完全發揮出它們捕捉碳的潛能，

their full carbon-capture potential.

需要數十年的時間。

And secondly,

第二，各位看看陸地表面， 已經被大量利用。

if you look at the land surface, you see that it's so heavily utilized.

We get our food from it, we get our forestry products from it,

我們從陸地表面取得食物， 取得林木產品，

biodiversity protection and water and everything else.

生物多樣性保護、 水，以及所有其他的運用。

To expect that we'll find enough space to deal with this problem,

期望我們能找到足夠空間 來處理這個問題，

I think is going to be quite problematic.

依我所見，是不切實際的。

But if we look offshore,

但，如果我們去近海看看，

wee see a solution where there's already an existing industry,

我們可在既有的產業中 找到一個解決方案，

and where there's a clearer way forward.

而且它有很清楚的未來方向。

The oceans cover about 70 percent of our planet.

地球表面約 70% 被海洋覆蓋。

They play a really big role in regulating our climate,

在調節我們的氣候上， 海洋扮演了很重要的角色。

and if we can enhance the growth of seaweed in them,

如果我們能增加 海洋中的海草生長，

we can use them, I think, to develop a climate-altering crop.

我想，我們就能利用它們 來開發出能改變氣候的作物。

There are so many different kinds of seaweed,

海草的種類非常多，

there's unbelievable genetic diversity in seaweed,

海草的基因多樣性非常驚人， 而且它的歷史悠久；

and they're very ancient;

they were some of the first multicellular organisms ever to evolve.

它們是最早的有演化的 多細胞生物之一。

People are using special kinds of seaweed now

現在有人將幾種特別的海草 用在特定用途上，

for particular purposes,

like developing very high-quality pharmaceutical products.

比如開發很高品質的藥品。

But you can also use seaweed to take a seaweed bath,

你也可以拿海草來做海草浴，

it's supposed to be good for your skin;

聽說對皮膚有益；

我無法保證這一點， 但你可以試。

I can't testify to that, but you can do it.

The scalability is the big thing about seaweed farming.

海草養殖有個很重要的特點 就是規模擴展性。

You know, if we could cover nine percent of the world's ocean

如果我們能用 9% 的全球海洋

in seaweed farms,

來做海草養殖場，

we could draw down the equivalent of all of the greenhouse gases

它能減少的所有溫室氣體量，

we put up in any one year,

等同於我們一整年釋出的量， 超過五百億噸。

more than 50 gigatons.

Now, I thought that was fantastic when I first read it,

當我初次讀到這項資訊時， 我覺得太棒了，

but I thought I'd better calculate how big nine percent of the world's oceans is.

但我想最好算一下 全球海洋的 9% 是多大。

結果是約 4.5 個澳洲，

It turns out, it's about four and a half Australias,

我目前住的地方的大小。

the place I live in.

目前我們離這個目標值有多遠呢？

And how close are we to that at the moment?

How many ocean-going seaweed farms do we actually have out there?

現在我們目前有多少個 海洋中的海草養殖場呢？

Zero.

零。

But we do have some prototypes, and therein lies some hope.

但我們確實有些樣板， 所以還是有希望的。

This little drawing here of a seaweed farm that's currently under construction

這張小圖是一個目前正在 建造中的海草養殖場，

tells you some very interesting things about seaweed.

圖中呈現出一些 關於海草的有趣資訊。

You can see the seaweed growing on that rack,

各位可以看到，海草在海面下 25 公尺的架上生長。

25 meters down in the ocean there.

It's really different from anything you see on land.

它和各位在陸地上 看到的東西很不一樣。

And the reason being that, you know, seaweed is not like trees,

原因是，你也知道的， 海草和樹木不同，

it doesn't have nonproductive parts

它沒有無生產力的部分，

like roots and trunks and branches and bark.

比如根、樹幹、樹枝和樹皮。

The whole of the plant is pretty much photosynthetic,

海草整體都可以行光合作用，

so it grows fast.

所以它生長很快。 海草每天能成長一公尺。

Seaweed can grow a meter a day.

And how do we sequester the carbon?

我們如何將碳隔離出來？

Again, it's very different from on land.

這也和陸地上的做法很不同。

All you need to do is cut that seaweed off --

你只要做一件事， 就是把海草切斷——

drifts into the ocean abyss,

讓它飄向海洋深處，

Once it's down a kilometer,

一旦到了一公里深，

the carbon in that seaweed is effectively out of the atmospheric system

海草中的碳就會脫離大氣系統，

for centuries or millennia.

數世紀或千年之久。

Whereas if you plant a forest,

如果種植的是森林，

you've got to worry about forest fires, bugs, etc.,

你就得擔心 森林大火、蟲害等等，

releasing that carbon.

會釋放除碳來。

The key to this farm, though,

不過，這種海草養殖的關鍵在於

is that little pipe going down into the depths.

一根向下深入海中的小管子。

You know, the mid-ocean is basically a vast biological desert.

基本上，海洋中部 就是一個浩瀚的生物沙漠。

There's no nutrients there that were used up long ago.

那裡沒有養分， 很久以前就用光了。

But just 500 meters down,

但，再下去五百公尺，

there is cool, very nutrient-rich water.

就有清涼、營養豐富的水。

And with just a little bit of clean, renewable energy,

只需要一點乾淨的，可再生能源，

you can pump that water up

就可以把這些水向上抽，

and use the nutrients in it to irrigate your seaweed crop.

用水中的營養來灌溉海草作物。

So I think this really has so many benefits.

我認為這有很多益處。

It's changing a biological desert,

它將海洋中部的生物沙漠

the mid-ocean,

into a productive, maybe even planet-saving solution.

改變成有生產力的， 甚至能拯救地球的解決方案。

So what could go wrong?

所以，這有可能出錯嗎？

Well, anything we're talking about at this scale

嗯，這種規模的任何事物，

involves a planetary-scale intervention.

涉及到全球性規模的干預。

And we have to be very careful.

我們得要非常小心。

I think that piles of stinking seaweed

我認為，那些發臭的海草堆，

are probably going to be the least of our problems.

其實可能還算是最小的問題。

There's other unforeseen things that will happen.

有其他未預見的事情會發生。

One of the things that really worries me, when I talk about this,

每當談到這點， 我最擔心的其中一件事，

is the fate of biodiversity in the deep ocean.

就是深海生物多樣性的命運。

If we are putting gigatons of seaweed into the deep ocean,

如果我們把數十億噸 海草丟入深海中，

we're affecting life down there.

我們會影響到下面的生命。

The good news is that we know

好消息是，我們知道

that a lot of seaweed already reaches the deep ocean,

在暴風雨之後， 很多海草已經沉到了深海中，

after storms or through submarine canyons.

或通過海底峽谷。

So we're not talking about a novel process here;

所以我們談的 這個過程並不是新的；

we are talking about enhancing a natural process.

我們談的是增強大自然的過程。

And we'll learn as we go.

我們會邊做邊學。

I mean, it may be that these ocean-going seaweed farms will need to be mobile,

可能這些海洋裡的海草養殖場 必須要是活動式的，

to distribute the seaweed across vast areas of the ocean,

才能把海草分送到 廣大海洋的各處，

rather than creating a big stinking pile in one place.

而不是在單一地點 創造出一個巨大的海草堆。

It may be that we'll need to char the seaweed --

我們可能會需要把海草燒焦——

so create a sort of an inert, mineral biochar

以產生出一種惰性的礦物性生物炭，

before we dispatch it into the deep.

然後再把它送到海洋深處。

We won't know until we start the process,

在尚未開始這過程之前不會知道，

and we will learn effectively by doing.

我們得要邊做邊學。

I just want to take you to contemporary seaweed farming.

我只是想要帶大家看看 現代海草養殖。

It's a big business --

它是個大事業——

it's a six-billion-dollar-a-year business.

每年六十億美金的事業。

These seaweed farms off South Korea --

南韓近海的海草養殖場——

you can see them from space, they are huge.

它們很巨大，從太空中可以看見。

And they're increasingly not just seaweed farms.

漸漸地，它們不再 只是海草養殖場。

What people are doing in places like this is something called ocean permaculture.

人們在這些地方做的是永續栽培。

And in ocean permaculture,

要做海洋永續栽培，

you grow fish, shellfish and seaweed all together.

就要同時養殖魚類、 甲殼類，和海草。

And the reason it works so well

它能運作得這麼順利的原因

is that the seaweed makes the seawater less acid.

是因為海草會讓海水的酸性下降。

It provides an ideal environment for growing marine protein.

提供了一個理想的環境， 讓海中的蛋白質生長。

If we covered nine percent of the world's oceans

如果我們能把永續栽培 擴展到全球海洋的 9%，

in ocean permaculture,

we would be producing enough protein in the form of fish and shellfish

我們就能以魚類和甲殼類的形式， 產生出足夠的蛋白質，

to give every person in a population of 10 billion

每年供應每人兩百公斤的 高品質蛋白質

200 kilograms of high-quality protein per year.

給一百億人口。

So, we've got a multipotent solution here.

所以，這個解決方案有多種用途。

We can address climate change, we can feed the world,

可以處理氣候變遷， 可以供應食物給世界，

we can deacidify the oceans.

可以減少海洋酸化。

The economics of all of this is going to be challenging.

這一切背後需要的經濟會很挑戰。

We'll be investing many, many billions of dollars

我們得要投資數十億美金 給這些解決方案，

into these solutions,

and they will take decades to get to the gigaton scale.

還要花上數十年才能 達到十億噸的規模。

The reason that I'm convinced that this is going to happen

我深信這個理想會成真，

is that unless we get the gas out of the air,

因為若我們不把溫室氣體 從空氣中除去，

it is going to keep driving adverse consequences.

它將會一直促成不良的後果。

It will flood our cities,

我們的城市會被洪水淹沒，

it will deprive us of food,

我們會喪失食物， 還會有各種內亂。

it will cause all sorts of civil unrest.

So anyone who's got a solution to dealing with this problem

所以，任何有解決方案 可以處理這個問題的人，

has a valuable asset.

就擁有珍貴的資產。

And already, as I've explained,

如我先前解釋的，

ocean permaculture is well on the road to being economically sustainable.

海洋永續栽培已經 朝向經濟永續性邁進。

You know, in the next 30 years,

在接下來的三十年內，

we have to go from being a carbon-emitting economy

我們得要從排放碳的經濟

to a carbon-absorbing economy.

轉變為吸收碳的經濟。

And that doesn't seem like very long.

這時間並不長。

But half of the greenhouse gases that we've put into the atmosphere,

但，我們送入大氣中的溫室氣體，

有一半就是在過去三十年間放的。

we've put there in the last 30 years.

My argument is,

我的主張是，

if we can put the gas in in 30 years,

如果我們花三十年 把這些氣體送入大氣，

we can pull it out in 30 years.

我們也能在三十年內將它們取出。

And if you doubt how much can be done over 30 years,

如果你懷疑三十年能做什麼，

just cast your mind back a century, to 1919,

就回想一下 1919 年，

compare it with 1950.

和 1950 年做比較。

Now, in 1919, here in Edinburgh,

1919 年，在愛丁堡，

you might have seen a canvas and wood biplane.

你可能看到用帆布 和木頭做的雙翼飛機。

Thirty years later, you'd be seeing jet aircraft.

三十年後，你看到噴射機。

Transport in the street were horses in 1919.

1919 年，路上的交通工具是馬。

By 1950, they're motor vehicles.

1950 年，變成是汽車。

1919, we had gun powder;

1919 年，我們用火藥；

1950, we had nuclear power.

1950 年，我們有了核能。

We can do a lot in a short period of time.

在這麼短的時間內， 我們能做的很多。

But it all depends upon us believing that we can find a solution.

但，這都要仰賴我們的信念， 相信我們能找到解決方案。

Now what I would love to do is bring together all of the people

我想要做的，

是集結所有對這方面有知識的人。

with knowledge in this space.

The engineers who know how to build structures offshore,

知道如何在近海 建造結構的工程師、

the seaweed farmers, the financiers,

海草養殖者、金融家、

the government regulators,

政府管理者、

the people who understand how things are done.

知道怎麼做的人。

And chart a way forward,

一同設計出向前走的路，如，

say: How do we go from the existing six-billion-dollar-a-year,

現有的海草產業規模 是每年六十億美金，

inshore seaweed industry,

我們要如何把它轉變成

to this new form of industry, which has got so much potential,

這種更有潛能的新形式產業，

but will require large amounts of investment?

但需要很大量的投資？

I'm not a betting man, you know.

我不是愛打賭的人。

But if I were,

但，如果是的話，告訴各位，

I'll tell you, my money would be on that stuff,

我會把我的錢下注在海草上。

it would be on seaweed.

It's my hero.

海草是我的英雄。

Thank you.

謝謝。

(Applause)

（掌聲）