Whatever happened to the hole in the ozone layer? - Stephanie Honchell Smith

翻译人员: Jenny Zhao 校对人员: Jacky He

In the 1980s, the world faced a huge problem:

上世纪 80 年代， 我们世界面临一个巨大的问题：

there was a rapidly expanding hole in the ozone layer.

臭氧层中有一个 正在迅速扩大的空洞。

So, what happened? And is it still there?

所以，发生了什么事？ 这个空洞还在吗？

Let’s go back to the beginning.

让我们先从头开始。

The Sun makes life on Earth possible,

太阳让地球上的生物能够存活，

but too much exposure to its UV radiation damages plant and animal DNA.

但过量的紫外线辐射 会损害植物和动物的 DNA。

Thankfully, about 98% of that radiation is absorbed by ozone molecules

值得庆幸的是，大约 98% 的 辐射被臭氧分子吸收

dispersed in the stratosphere,

分散在平流层；

which are continuously broken apart and reformed in this process,

它们在此过程中 不断地分解和重造，

maintaining a delicate equilibrium.

保持着一个微妙的平衡。

But in the early 1970s, two chemists— Mario Molina and Sherwood Rowland—

但在 1970 年代初期，两位化学家 ——马里奥·莫利纳和舍伍德·罗兰——

demonstrated that widely used chemicals called chlorofluorocarbons, or CFCs,

证实人们广泛使用的 一种化学物质氯氟烃或 CFC，

could upset this balance.

可能会打破这种平衡。

CFCs were developed in the 1920s by three US-based corporations

CFC是在 1920 年代 由三个美国公司开发的

as coolants for refrigerators.

用于冰箱的冷却剂。

Unlike existing alternatives— such as ammonia or methyl chloride—

不同于现有的替代品 —如氨或氯甲烷—

CFCs were non-flammable and non-toxic—

CFC 不易燃且无毒—

meaning they wouldn't burst into flames or cause deadly gas leaks.

这意味着它不会起火 或导致致命的气体泄漏。

They also made great propellants, foaming agents, and fire-retardants.

用它还可以制造很好的 推进剂，发泡剂和阻燃剂。

CFCs soon found their way into a variety of everyday items

CFC 很快就被加入 各种日常用品中

and became a multi-billion dollar per year industry.

并成为了一个年收益 数十亿美元的产业。

In the lower atmosphere, CFCs don’t break down or react with other molecules.

在低层大气中，CFC 不会分解 或与其他分子发生反应。

But Molina and Rowland showed that in the stratosphere,

但莫利纳和罗兰 表明了在平流层里，

they're broken apart by UV light, releasing chlorine atoms.

它们被紫外线分解， 释放出氯原子，

These then react with ozone,

而其与臭氧发生反应，

destroying it faster than it can be replenished.

将其消除，远超过臭氧再生的速率。

A single chlorine atom can destroy thousands of ozone molecules

一个氯原子可以破坏 数千个臭氧分子，

before finally reacting with something else and forming a stable molecule.

在最终与其他物质反应 并形成稳定的分子之前。

Seeing the threat to their bottom line,

看到对他们根基的威胁之后，

CFC producers pushed back to discredit the scientists,

CFC 生产商开始诋毁科学家，

even accusing them of working for the KGB.

甚至指控他们为 KGB 工作。

Initial estimates showed that within 60 years,

初步估计表明在 60 年内，

CFCs could reduce ozone concentrations by 7%.

CFC 可使臭氧浓度降低 7%。

But by 1985, it became clear that ozone depletion, especially over Antarctica,

但到了 1985 年，很明显 臭氧的消耗，尤其在南极上空的

was happening much faster.

发生得快很多。

Here, the extremely cold temperatures and unique structure of Antarctic clouds

在这儿，极寒的温度 和独特的南极云层结构

accelerated ozone loss.

加速了臭氧的损失。

Scientists stationed in Antarctica noticed a massive drop

驻扎在南极洲的科学家 注意到了每年春天

in overhead ozone occurring every spring.

上空臭氧的大幅下降。

Satellite data revealed the vast extent of these losses

卫星数据揭露了这些 损失的具体程度，

and chemical tests confirmed that the cause was unquestionably CFCs.

而化学测试证实， 无疑是 CFC 导致的。

NASA soon released visualizations, which were broadcast around the world

美国国家航空航天局很快便发布了 视图，并在全世界播出

and captured public attention.

引起了公众的注意。

If ozone depletion continued, rates of skin cancer would skyrocket.

如果臭氧消耗继续下去， 皮肤癌的发病率将会飙升。

Photosynthesis would be impaired, making plants—

光合作用会受危害，使植物—

including rice, wheat, and corn—

包括大米，小麦和玉米—

less productive and more susceptible to disease.

生产力降低，更容易染病。

Global agricultural production would plummet,

全球农业产量将直线下降，

and entire ecosystems would collapse.

并且整个生态系统都会崩溃。

But many politicians— weighing immediate economic concerns over long-term ones—

但许多政客，考虑眼前的 而非长期的经济问题，

disagreed about what to do.

在提出方案的时候出现了分歧。

The fight to ban CFCs found two unlikely allies

禁止 CFC 的斗争中 形成了一对不寻常的盟友，

in US President Ronald Reagan and UK Prime Minister Margaret Thatcher.

美国总统罗纳德·里根 和英国首相玛格丽特·撒切尔。

Despite their general opposition to government regulation,

尽管他们反对政府管控，

Reagan, who had undergone treatment for skin cancer,

因皮肤癌而接受治疗的里根，

and Thatcher, who was trained as a chemist,

还有接受化学教育的 撒切尔夫人，

recognized the need for immediate action.

认识到了采取立刻行动的必要性。

The US and UK, along with Canada, Norway, Sweden, and Finland,

美国和英国以及加拿大， 挪威，瑞典和芬兰，

led calls for an international ban on CFCs.

带头呼吁国际上 禁用 CFC。

In 1987, representatives signed the Montreal Protocol,

1987年，代表们签署了 《蒙特利尔议定书》，

requiring the rapid phasing out of CFCs

要求迅速淘汰 CFC，

and creating a fund to assist Global South countries

并建立一项基金来 援助全球南方国家

in obtaining affordable, non-ozone depleting alternatives.

以利用经济的，不损耗臭氧的替代品。

It was later ratified by every country on Earth—

它后来由地球上全部国家批准—

the only treaty in history to achieve this.

历史上唯一实现 这一目标的条约。

In 1995, Molina, Rowland, and their Dutch colleague Paul Crutzen,

1995年，莫利纳，罗兰和 他们的荷兰同事保罗·克鲁岑，

were jointly awarded the Nobel Prize in Chemistry.

共同获得了诺贝尔化学奖。

As the use of CFCs declined,

随着 CFC 的使用逐渐减少，

the ozone hole began shrinking,

臭氧空洞开始缩小了，

and is predicted to disappear entirely by 2070.

预计到2070年将完全消失。

But we’re not out of the woods yet.

但我们还没有完全走出困境。

While the ban was a win for the climate, as CFCs are potent greenhouse gases,

这个禁令对气候十分有利； CFC 是强效温室气体，

the alternatives that replaced them— hydrofluorocarbons, or HFCs— are too.

而取代它们的替代品， 氢氟碳化物，即 HFC 也是。

While generally less potent than CFCs,

虽然通常不及 CFC，

HFCs still trap more heat than carbon dioxide

HFC 仍然较二氧化碳 留住更多的热量

and are contributing to climate change.

并且正在加剧气候变化。

To address this, in 2016, the Kigali Amendment

为了解决这个问题，2016年， 基加利修正案

was added to the Montreal Protocol,

被加入了《蒙特利尔议定书》，

calling for an 85% cut in global HFCs by 2047.

呼吁在 2047 年实现 全球 HFC 85% 的削减。

This alone could avoid up to 0.5°C of global warming by the end of the century.

到本世纪末，仅此一项就可以 避免高达 0.5 ℃ 的全球变暖。

Today, as we face the existential threat of climate change,

今天，当我们面临气候 变化的生存威胁时，

the Montreal Protocol serves as a model for the decisive global cooperation

我们需要像《蒙特利尔议定书》这类 全球决定性合作典范

we need to combat it.

以对付它。

The question is, what will it take for us to come together again?

那么问题来了； 什么会让我们再次团结起来？