Rachel Pike: The science behind a climate headline

翻译人员: Wang Qian 校对人员: Chaoran Yu

今天我想跟大家说说

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

有关于报纸头条新闻背后的

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

科学家们所付出的努力

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

事关气候变化时，报纸头版是这样的

这个是关于空气质量和烟雾的头条

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

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

它们是大气科学的两个分支

Recently, the headlines looked like this

这是最近的报纸头条，

when the Intergovernmental Panel on Climate Change, or IPCC,

当时，联合国政府间气候变化专门委员会，即IPCC

发布了一份针对理解大气系统形势的报告

put out their report

on the state of understanding of the atmospheric system.

这份报告由来自40个国家的

That report was written by 620 scientists from 40 countries.

共620名科学家撰写

They wrote almost 1,000 pages on the topic,

在这个主题上，他们倾注了近一千页的努力

and all of those pages were reviewed

同时，来自113个国家的400多位科学家

by another 400-plus scientists and reviewers

和观察员审读了整份报告

from 113 countries.

It's a big community;

这是一个很大的群体，

such a big community, in fact,

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

事实上，我们年会是全球物理学界最大的会议

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

每年开会时，逾15000名科学家云集洛杉矶

Every one of those scientists is in a research group,

他们中的每一个都代表着一个研究小组

以及每个小组的大量研究课题

and every research group studies a wide variety of topics.

在剑桥，我们的研究方向各式各样

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

有影响天气和气候的厄尔尼诺现象

which affects weather and climate,

to the assimilation of satellite data,

有卫星数据同化

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

还有生产生物燃料的农作物的排放，这也是我正好在研究的

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

在每一个研究领域里，当然远不止这些

都有像我这样的博士生

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

我们都在研究非常狭窄的课题

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

窄到只是寥寥几个反应或者几个分子

我正在研究其中一种叫异戊二烯的分子

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

大家看，是种小有机分子，你们可能从未听过

It's a small organic molecule.

You've probably never heard of it.

The weight of a paper clip is approximately equal

一个回形针的质量大约等同于

10的21次方个异戊二烯分子

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

But despite its very small weight,

尽管这种分子很轻

enough of it is emitted into the atmosphere every year

每年排放到大气中的该种分子的质量相当于

地球上所有人类的体重总和

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

这可是很大一堆东西，跟甲烷的总质量相当了

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

正因如此，这种分子对大气系统举足轻重

And because it's so much stuff,

it's really important for the atmospheric system.

这种分子是如此重要

Because it's important to the atmospheric system,

以至于我们不遗余力的去研究它

we go to all lengths to study this thing.

我们使它进行化学反应，然后看看反应遗留的分子碎片

We blow it up and look at the pieces.

这是位于西班牙的EUPHORE装置的烟雾室

This is the EUPHORE Smog Chamber in Spain.

分子在大气中经过充分的燃烧

Atmospheric explosions, or full combustion,

这个过程所花费的时间比在你车里反应所花的长15000倍

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

即便如此，我们仍然观察反应结果

But still, we look at the pieces.

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

我们在超级计算机上运行大量的模型

这正好是我在干的事

Our models have hundreds of thousands of grid boxes

我们的模型里有成百上千的网格

calculating hundreds of variables each, on minute timescales.

每个网格在分钟级的时间尺度上计算成百个变量

It takes weeks to perform our integrations,

我们花费数周的时间整合数据

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

为了理解究竟发生了什么，

我们进行数十次的整合

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

同时，我们在世界各地搜寻这种物质

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

最近我在马来西亚参加了一个野外研究项目，别处也有类似的项目

We found a global atmospheric watchtower there

我们在当地雨林里建立了一个全球大气监视塔

in the middle of the rainforest,

我们在塔上悬挂了

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

价值数十万美元的科学设备

这是都是为了探测异戊二烯分子

off this tower,

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

当然，也可以探测别的存在的东西

这就是雨林中的那座塔，这是从上看

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

再从下方看看

and the tower from below.

在上次的野外考察中我们还动用了

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

FAAM旗下的BA146型飞机

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

这种飞机通常客容量在120至130人之间

normally flies 120 to 130 people,

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

也许在座的各位今天就是搭乘类似的飞机到达会场的

But we didn't just fly it.

但科学家的工作可不只是搭乘飞机这样简单。

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

为了测量这种分子飞机的飞行高度离森林中天棚似的树荫仅为100米--很危险

to measure this molecule -- incredibly dangerous stuff.

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

为了进行测量，飞机要保持在一个特殊的飞行角度

we hire military and test pilots to do the maneuvering;

为此我们请来军事和飞机试驾飞行员来驾驶飞机

此外我们还准备了特殊飞行许可

we need special flight clearance.

当飞机一路从河谷飞过，阻力就已高达2G

As you come around the banks in these valleys,

the forces can get up to two Gs;

要进行测量

the scientists must be completely harnessed in

科学家们就一定要在机舱里进行控制

in order to make measurements while on board.

想象一下

So as you can imagine,

我们的飞机机舱可不是普通飞机可以媲美的

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

它是测量分子的空中实验室

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

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

这是我们为了解化学分子所进行的努力

And when one student like me has some sort of inclination

像我一样的学生们要是对某一分子情有独钟

或有独到见解

or understanding about that molecule,

就会把自己的看法写成科学论文

they write one scientific paper on the subject.

然后对那几十种分子的研究就会积累

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

几十篇文章

on a few dozen processes or molecules.

这样知识体系就构建起来了

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

次级学科，或次次级学科就形成了

or one sub-subsection,

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

包括IPCC在内，我们有很多这样的研究

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

IPCC的11个章节中

都有六至十个次级学科

So you can imagine the scale of the effort.

科学的努力付出可见一斑

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

我们的每一篇研究报告

都会有一个

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

为普通大众所写的摘要

And we hand that summary to journalists and policy makers

然后摘要就交给记者和政策制定者

in order to make headlines like these.

新闻报道的标题就形成了

非常感谢

Thank you very much.

(Applause)

（鼓掌）