地球的力量 第1集 火山(18)火山的作用舉足輕重

These, too, are the results of volcanic activity

這個(gè)系統(tǒng)同樣也是火山活動(dòng)的產(chǎn)物

but they are found in the deepest parts of theoceans.

存在于大洋最深的底部。

Today, they support an extraordinary diversity of life.

如今 它支撐著異常豐富的生命。

But four billion years ago,

有人認(rèn)為40億年前，

it's thought that the combination of high temperatures

這些噴口造成的高溫和

and rich chemicals that the vents produce might have stimulated the emergence of life.

豐富化學(xué)物質(zhì)刺激了生命的誕生。

but the role of volcanoes went beyond just kick starting life.

火山的作用遠(yuǎn)遠(yuǎn)不局限于推動(dòng)生命的誕生。

they have played a critical role in nurturing and protecting it, too.

在養(yǎng)育與防護(hù)生命方面 火山的作用也舉足輕重。

During Earth's infancy,

地球幼年時(shí)期

the sun wasn't burning as brightly as it does today.

太陽的亮度不比如今

In fact, it was about 30 percent cooler.

實(shí)際上 那時(shí)太陽比如今要冷30%

With a dimmer sun bathing the planet in weaker sunlight,

植物沐浴在黯淡的陽光里

Earth was actually in danger of freezing.

當(dāng)時(shí)地球?qū)嶋H上面臨凍僵的危險(xiǎn)

It was the volcanoes that provided young,vulnerable planet

正是火山為年幼虛弱的地球提供了溫暖

with a way to keep warm,but not in the way you might think.

不過具體的方式與您的猜想可能不同

Earth wasn't warmed up by all that hot lava spewing out,

溫暖地球的并非火山噴出的熔巖

but by an extraordinary gas Nthat volcanoes pumped out.

而是火山噴出的某種非凡氣體

And that gas was carbon dioxide.

這種氣體就是二氧化碳