Rachel Pike: The science behind a climate headline

Translator: Louise LIANG Reviewer: Raymond Ou

I'd like to talk to you today about the scale of the scientific effort

今日我想同大家講下

你哋喺報紙上見到嘅頭條

that goes into making the headlines you see in the paper.

背後所投入嘅科研程度

Headlines that look like this when they have to do with climate change;

好似呢個氣候變化嘅頭條

仲有呢個同空氣質量 或者霞氣有關嘅頭條

and like this when they have to do with air quality or smog.

They're two branches of the same field of atmospheric science.

佢哋係大氣科學嘅唔同分支

Recently, the headlines looked like this

近排嘅頭條就好似呢個

when the Intergovernmental Panel on Climate Change, or IPCC,

當政府個氣候變化專門委員會 簡稱 IPCC

提交對大氣系統了解程度嘅報告

put out their report

on the state of understanding of the atmospheric system.

呢份報告由來自 40 個國家 620 位科學家共同撰寫

That report was written by 620 scientists from 40 countries.

They wrote almost 1,000 pages on the topic,

寫咗近一千頁嘅報告

and all of those pages were reviewed

而每一頁又經過另外 400 幾位

by another 400-plus scientists and reviewers

來自 113 個國家嘅科學家 同審稿人審核先至發表

from 113 countries.

It's a big community;

呢一個係龐大嘅團隊嚟

such a big community, in fact,

事實上，佢大到令我哋嘅年會 變成咗世界上最大嘅科學家會議

that our annual gathering is the largest scientific meeting in the world.

Over 15,000 scientists go to San Francisco every year for that.

其中每年有超過 15,000 名科學家 會去三藩市參加年會

Every one of those scientists is in a research group,

而每一位與會者都嚟自 其中一組研究團隊

每一組研究團隊致力研究 一系列不同課題

and every research group studies a wide variety of topics.

對於我所在嘅劍橋團隊

For us at Cambridge, it's as varied as the El Niño Oscillation,

研究範疇從影響天氣同氣候嘅 厄爾尼諾現象

which affects weather and climate,

to the assimilation of satellite data,

到衛星數據嘅同化

to emissions from crops that produce biofuels, which is what I study.

以至製造生物燃料嘅農作物嘅氣體排放 ——亦係我嘅研究內容

And in each one of these research areas, of which there are even more,

而喺每一個研究領域之中有好多

我同其他博士研究生

there are PhD students, like me, and we study incredibly narrow topics,

都係研究非常狹小嘅課題

things as narrow as a few processes or a few molecules.

專門到一小部分進程或者某幾個分子

而我研究嘅其中一個分子係異戊二烯

And one of the molecules I study is called isoprene, which is here.

就喺呢度。佢係一個好細嘅有機分子 你可能從來未聽過

It's a small organic molecule.

You've probably never heard of it.

The weight of a paper clip is approximately equal

一個曲別針嘅重量大概相當於

900×10^21 大約 10 嘅 21 次方個異戊二烯分子

to 900 zeta-illion -- 10 to the 21st -- molecules of isoprene.

But despite its very small weight,

雖然輕若無物

enough of it is emitted into the atmosphere every year

每年釋放到大氣中嘅數量

卻足以抵得上全人類嘅重量

to equal the weight of all the people on the planet.

數量之大同甲烷嘅重量相當

It's a huge amount of stuff. It's equal to the weight of methane.

正因為咁 佢對大氣系統有舉足輕重嘅影響

And because it's so much stuff,

it's really important for the atmospheric system.

亦係呢個嘅影響

Because it's important to the atmospheric system,

我哋竭盡全力去研究佢

we go to all lengths to study this thing.

我哋將佢分解爆破再研究所得嘅碎片

We blow it up and look at the pieces.

呢個係位於西班牙嘅 EUPHORE 煙霧艙

This is the EUPHORE Smog Chamber in Spain.

雖然呢度大氣爆炸或者完全燃燒要比

Atmospheric explosions, or full combustion,

takes about 15,000 times longer than what happens in your car.

私家車慢 1.5 萬倍

但我哋仍然會分析呢啲碎片

But still, we look at the pieces.

We run enormous models on supercomputers; this is what I happen to do.

我哋用超级電腦做大量嘅模型演算

呢個係我做嘅嘢

Our models have hundreds of thousands of grid boxes

我哋嘅模型用上成千上萬個 超級電腦嘅櫃

calculating hundreds of variables each, on minute timescales.

每個負責計算幾百個 以一分鐘為單位嘅變量

It takes weeks to perform our integrations,

整合呢啲數據需要幾個星期時間

and we perform dozens of integrations in order to understand what's happening.

而我哋要做幾十種整合 來了解發生緊嘅情況

We also fly all over the world looking for this thing.

我哋仲飛到世界各地去搵呢種分子

I recently joined a field campaign in Malaysia -- there are others.

最近我就同其他人去咗馬來西亞考察

We found a global atmospheric watchtower there

我哋喺嗰度設立咗一個 「全球大氣瞭望塔」

in the middle of the rainforest,

佢位於熱帶雨林嘅中央

我哋喺嗰度懸掛咗 價錢高昂嘅嘅科學儀器

and hung hundreds of thousands of dollars' worth of scientific equipment

off this tower,

用來尋找異戊二烯同其他嘢

to look for isoprene and other things while we were there.

呢個係從天空望落雨林中間嘅瞭望塔

This is the tower in the middle of the rainforest from above,

呢個係由下至上嘅角度

and the tower from below.

我哋仲為呢次嘅考察配備咗飛機

On part of that field campaign we even brought an aircraft with us.

型號係 BA146 屬於 FAAM（氣測量飛行設備公司）

And this plane, the model BAe-146, which was run by FAAM,

通常可以運載 120 到 130 人

normally flies 120 to 130 people,

so maybe you took a similar aircraft to get here today.

你哋今天可能係坐類似嘅機型嚟呢度

But we didn't just fly it.

但係，我哋唔單止飛 我哋仲喺樹冠上空 100 米飛

We were flying at 100 meters above the top of the canopy

就係爲咗測量分子，不過亦係危險行為

to measure this molecule -- incredibly dangerous stuff.

We have to fly at a special incline to make the measurements;

我哋需要以特殊嘅傾斜角度飛行 來進行測量

we hire military and test pilots to do the maneuvering;

所以聘請咗軍事飛行員 同測試飛行員來操作飛機

我哋需要獲得特殊飛行許可

we need special flight clearance.

當環繞呢啲山谷彎位飛行時 重力可達2G

As you come around the banks in these valleys,

the forces can get up to two Gs;

所以科學家必須全程扣上安全帶

the scientists must be completely harnessed in

先至能夠喺飛行期間做測量工作

in order to make measurements while on board.

正如你所想像嘅

So as you can imagine,

呢架飛機嘅內部 同你哋度假坐嘅嗰啲完全唔一樣

the inside of the aircraft doesn't look like one you'd take on vacation.

佢係一個飛行中嘅實驗室

It's a flying laboratory we took to make measurements of this molecule.

我哋用佢來測量呢一種分子

We do all this to understand the chemistry of one molecule.

我哋所做嘅一切都係爲咗 了解個分子嘅化學性質

And when one student like me has some sort of inclination

當好似我咁樣嘅學生對個分子 有咗某種想法或者了解之後

or understanding about that molecule,

佢哋會以此為題寫一篇科學論文

they write one scientific paper on the subject.

從嗰次考察裏面我哋大概可以

And out of that field campaign we'll probably get a few dozen papers

就住幾個過程或者分子 而去寫幾十篇論文

on a few dozen processes or molecules.

而當知識量建立起

As a body of knowledge builds up, it will form one subsection,

佢就會成為好似 IPCC 評估嘅 一個副章節，或者副副章節

or one sub-subsection,

of an assessment like the IPCC, although we have others.

當然我哋仲有其他評估

And each one of the 11 chapters of the IPCC has six to ten subsections.

喺 IPCC 報告嘅 11 個章節當中

每一章都有 6 到 10 個副章節

So you can imagine the scale of the effort.

咁樣你就可以想像 其中需要付出嘅努力有幾多

In each one of the assessments we write, we always tag on a summary,

喺我哋撰寫嘅每一份評估當中

都會包含一個摘要

and the summary is written for a non-scientific audience.

摘要係寫畀冇科學背景嘅讀者嘅

And we hand that summary to journalists and policy makers

我哋將摘要提供畀記者同決策者

in order to make headlines like these.

用來做咁樣嘅頭條

Thank you very much.

多謝

(Applause)

（掌聲）