90 people were hospitalized, and a 12-year-old boy died.

90 人被迫住院觀察，一名 12 歲男童死亡。

Soon, Russian officials identified what had killed him.

很快地，俄羅斯官方發現了原因。

The deadly infectious disease, anthrax.

致命的傳染性疾病－炭疽病。

The outbreak had started among reindeer.

該疾病爆發的起源是馴鹿群。

To contain the spread, they burned over 2,000 reindeer carcasses.

為了控制疫情，俄方焚燒了超過 2,000 具馴鹿屍體。

The strange thing was, there hadn't been an anthrax outbreak in the area for more than 70 years.

奇怪的是，這個地區已經 70 年沒有炭疽病爆發的跡象了。

So, to figure out where it came from, scientists started looking underground.

為了找出來源，科學家開始往地底尋找。

In the coldest parts of the world, there's a layer of the Earth that stays frozen all year.

在地球最冷的部分，有一層全年凍結的土層。

Every summer, the soil above it thaws, but this deeper layer stays hard as rock.

每年夏天，上層的泥土會融化，但深層仍然與石頭一樣堅硬。

This is permafrost.

這叫做永凍土層。

Most permafrost is here, in the Northern Hemisphere around the Arctic.

大部分的永凍土都分佈在這，北半球的北極區。

And because it never thaws, permafrost acts kind of like the freezer in your kitchen.

而因為不會融化，永凍土的作用就有點像廚房裡的冷凍庫。

When plants and animals here die, they don't actually decompose.

當此處的植物與動物死去，牠們不會腐爛。

Instead, they become preserved in the frozen earth, like a time capsule.

牠們反而像是時光膠囊般地被保存在凍結的地球裡。

And it's been that way for thousands of years.

數千年來都是如此。

But that's changing.

但這有了改變。

Today, humans are burning carbon and making the atmosphere warmer.

現在，人類排放碳化物，讓大氣變暖。

And that's causing the permafrost to thaw and shrink.

這讓永凍土開始融化、縮小。

By 2100, only these areas will still have any permafrost.

到了 2100 年，只有這些地區仍會保有永凍土。

And that's causing some problems.

而這造成了一些麻煩。

When permafrost melts, the land above it becomes unstable, which can lead to landslides.

當永凍土融化，上頭的土地會變得不穩定，進而導致土地崩解。

Man-made structures start to fall apart, as the ground underneath them collapses.

因為土地崩解，人造建築開始陷落。

And dead plants and animals that had been frozen for years are starting to thaw out.

多年前死去、被凍在地底的動植物開始融化跑出地面。

As they're exposed to air and bacteria, this organic material starts to decompose.

當牠們接觸到空氣與細菌，這些有機物開始腐爛分解。

That releases greenhouse gases like carbon dioxide and methane.

這會釋放溫室氣體，如二氧化碳與甲烷。

But that's not all it releases.

但這不是唯一被釋放出來的東西。

In Siberia, scientists think that the anthrax outbreak came from a long-dead reindeer carcass that thawed out along with the permafrost.

西伯利亞的科學家認為，炭疽病的爆發起源是多年前死去、而現在從永凍土裡融化出地面的馴鹿屍體。

Anthrax spores from the carcass would have spread across the area and infected reindeer grazing nearby.

從屍體跑出的炭疽病孢子在該區域散播，且感染在當地吃草的馴鹿。

And it's not just anthrax.

且，不僅僅只有炭疽病。

Scientists worry that, as permafrost melts, it could unearth all sorts of diseases we thought we had under control.

科學家擔憂當永凍土融化後，會釋放數種我們以為已經控制住的疾病。

35 million people live around permafrost.

永凍土附近居住著 3,500 萬人。

But the carbon released, as permafrost melts, will accelerate the impacts of climate change everywhere.

但隨著碳化物釋放、永凍土融化，會加速的各地氣候變遷。

Rising seas, heat waves, droughts in some places, and floods in others.

海平面上升、熱浪，某些地方出現乾旱，而某些地方水災。

And now we can add one more thing to that list, diseases we thought we conquered.

現在氣候變遷的影響再添增一項－人類自認已掌控住的疾病。