这是我们的行星:地球
It is an remarkable, ever-changing world, full ofnatural wonders.
这是一个神奇的千变万化的世界 充满着各种自然奇观
But there's more to Earth than this, much more.
但是地球本身还有比自然景观更奇特的东西
Because our planet is unique in the solar system,
因为我们的行星在整个太阳系是独一无二的
Perhaps even in the universe.
甚至在整个宇宙也是如此
4.5 billion years have made it a world of extraordinary landscapes
45亿年的时光地球形成了独特的风景地貌
and a home to life.
成了适宜人类生存的家园
My name is Iain Stewart.And I want to show you
我叫伊恩·斯图尔特 我将向您介绍
how our planet works.
我们美妙的星球的运行原理
I'm going to explore volcanoes.
我将从火山开始讲起
They're terrifyingly destructive.
火山具有极大的破坏力
But they're also the most fundamentalforce on the planet.
但是它们仍然是地球上最根本的自然力量
Volcanoes are part of a global system that continually reshapes our world
火山是地球系统的一部分它们一直在改变着地貌
They hold the key to the origins of life on Earth.
火山在很大程度上决定了地球的生命起源
They saved the planet from possibly the biggest crisis it's ever faced.
在地球面临最大危机的时候是火山拯救了地球
And they've even formed a partnership with life
它们甚至和生命相互依存
that keeps our planet habitable.
给地球生物提供了适宜生存的环境
