如今地球表面平均溫度為15攝氏度
700 million years ago,it was much colder.
7億年前,要冷得多了
That average surface temperature plummeted to minus 50,5-0 degrees celsius.
平均表面溫度降至負50攝氏度
Most of the Sun's heat was reflected back to space.
太陽熱量大多數都會被反射回太空
it looked like that the Earth might never heat up again.
看起來地球將永遠無法回暖
but clearly something happened.
但顯然發(fā)生了某些事情
It was volcanoes that came to the rescue.
出手挽救的正是火山
They eruped with tremendous force,
火山噴發(fā)
even blasting through the ice sheets that covered much of the planet.
突破覆蓋整個行星厚厚的冰層
It must been an extraordinary time.
那必定是個非凡時代
The nearest we have experienced was in 2004
與其最接近的是2004年
when an eruption was filmed busting through an ice sheet in Central Iceland.
當時冰島中部一次火山噴發(fā) 即突破了冰層,并被攝像記錄
This is what would have happened millions of years ago,
億萬年前的情況\N必定也是如此
but on a global scale.
而且是全球規(guī)模的
The heat from volcanoes would have melted holes in the ice,
火山的熱量肯定在冰層中熔化了一些孔洞
but that is not what saved our planet.
但那并不是地球得救的原因
it was the tons of carbon dioxide gas it released that did the trick.
功績屬于火山釋放的數以噸計的二氧化碳