紫外线损坏DNA 并使正常细胞癌变 UV radiation breaks down DNA and turns healthy cells cancerous.
如果我们受阳光直射 If we were hit by the full force of the sun,
地球将变得无菌 plants would be sterilized...
微生物会被消灭 microscopic life would be sterilized...
地球上将不存在生命 life couldn't be sustained on the surface of the earth.
紫外线是致命的 所以我们为什么 Ultraviolet light is vicious so how come we're
不会被烧成碎片 not burned to a crisp?
答案就在我们上空 The answer is high above us.
太阳向我们发射致命的紫外线 The sun slings deadly UV light at us...
但是大部分都在途中被一层由分子组成的薄膜 but most of it is stopped in its tracks by a thin blanket
即臭氧层 所阻止 of molecules that we call the ozone layer.
臭氧层是我们在空中的的第二道屏障 但它是脆弱的 The ozone layer is our second shield in the sky but it's fragile,
极其脆弱 extremely fragile.
三十年前 我们发现人造化学物质造成了 30 years ago, we discovered manmade chemicals had punched
臭氧空洞 a hole in the ozone layer.
就任这空洞存在吗 Is that hole here to stay?
等着使人类灭亡吗 Waiting around to kill us?
今天我们在努力探寻 Today we're trying hard to find out.
埃尔卡拉法特 阿根廷
摩根 桑德克将测试臭氧采样的理想平面 Morgan Sandercock is about to test an experimental plane perfect for sampling ozone.
继续 加压 Go ahead, go, pressurizing.
我觉得我们能上升至九万英尺 吉姆 你准备好出发了 We think we can go as high as 90,000 feet. Jim, you're ready to go.
摩根 桑德克 高空滑翔机飞行员
我准备好了 I'm ready.
这是勇敢者的工作【】 That's the big boy territory.
这里事情会很容易出错 That's where things can wrong very, very quickly.
如果机舱压力不够 飞行员会很容易 If we lose cabin pressure, then the pilots could very
晕过去 我们也没有任何自动系统 easily pass out and we don't have any automatic systems to
来使其恢复 recover from that.
准备出发 Getting ready to roll.
滑翔机在如此高空 听起来很危险 Now a glider might sound like a dangerous choice so high up,
但是滑翔机没有引擎 即它不会污染 but gliders don't have engines which means they can't pollute
实验样本 the team's samples.
收到消息 起落架已升空【】 Got a firm count, dolly off.
收到 起落架升空 翼轮升空 Count, dolly is off, wing wheel is off.
好的 11:32升空 Okay, rolling at 11:32.
11:32 如果可以的话请写下时间【】 11:32, written down, if you can get us the time.
空降 Airborne.
普兰滑翔机借助南安第斯山脉的上升气流 The Perlan glider uses air rising over the southern Andes
来达到极高的高度 to reach extraordinary heights.
- 空速70节 - 看起来真美 - Air speed, 70 knots. - Looking beautiful,.
美极了【】 Terrific, yeah.
52000英尺使它成为飞得最高的滑翔机 52,000 feet up makes this the highest glider
但你必须到达此高度才能拍下臭氧层好看的照片 flight ever but you've gotta get this high to get a great picture of the ozone layer.
好消息是幸亏有对于使用有害化学物质的 The good news is that thanks to a global ban on ozone
全球禁令 空洞似乎在逐渐愈合 harming chemicals, it looks like the hole is healing up.
我们的屏障正在重生 Our shield is regenerating.
我们的地球不是无生命的物体 Our planet is not an inanimate object.
它是一个可以自愈的生命体 It's a living thing and it can heal itself.
当我们发现臭氧空洞时 When we discovered the hole in the ozone layer,
人类共同努力 禁止有害物质的使用 mankind did come together on that one and we banned those substances.
杰瑞 林恩格 曾在太空143天
你低头 就能看见这脆弱的星球 它面对极度的危险 You look down and you see this fragile planet which supports life
仍孕育生命 on its surface in the face of the incredible
因此我认为 你应该更加在意 hostility and so you become much more sensitive,
保护它的重要性 I think, to the need to protect it.
不论怎么看 臭氧层都很特殊 Any way you look at it, the ozone layer is pretty special.
这层屏障保护了我们几百万年 This shield has looked after us for millions of years,
在猿猴变成人之前 even before mankind came down from the trees, even before the
甚至在恐龙存在之前 even before the dinosaurs walked the earth.
没有臭氧层就不会有人类 Without the ozone layer there would be no human race.
地球上的生命将只存在于水中 Life on earth would be trapped under water.
在地球与太阳的斗争中 太阳 In Earth's battle with the sun, the sun has
总是占上风 often had the upper hand.
现在 臭氧层保护我们不受紫外线照射 但很久以前 Today the ozone layer protects us from UV but once upon a time,
它并不存在 it wasn't there.
唯一安全的地方实在水面之下 The only safe place for life was under the waves.
如果三十亿年前没出现一个可以 Life would probably still be down there if it wasn't for something
光合作用的新物种 new that emerged nearly three billion years ago and found a way
生命也许现在还只能在水下 to use sunlight to its advantage.
几亿年前 当远古生物首次利用太阳光能 Billions of years ago as ancient organisms first harnessed the energy of the sun,
它们开始创造一种废物 they began producing a waste product.
杰夫 霍夫曼 曾在太空50天
氧气 Oxygen.
开始只是很少的个体 然后几千个创造出几百万个 At first it was just a few individuals, but thousands became millions.
几百万给创造出数万亿个 Millions became trillions.
全部生产着氧气 All bubbling up oxygen.
当氧气上升到大气中时 When oxygen gas rises high into the atmosphere
神奇的事情发生了 something very special happens to it.
它转化成了有保护性的臭氧 It transforms into protective ozone.
在臭氧层的保护下 先是微生物 Under the shelter of this ozone layer, first microbes
随后真菌和植物都从水中迁出 then fungI and plants migrated out of the water.
这意味着更多的氧气被创造 And this meant even more oxygen was being produced,
进一步加强了对阳光中紫外线的防护 further strengthening our shield against the sun's UV light.
这将成为我们地球上 And this would help make possible one of our planet's
最重要的时刻之一 most defining moments.
由于被一层前所未有的厚厚的臭氧层所保护 Protected by a thicker ozone layer than ever before,
地球向生命敞开了新世界的大门 a whole new world of possibilities opened up for life on earth.
我们认为 当四亿年前 We think it was about 400 million years ago when
初等脊椎动物蹒跚在干燥的陆地上时 simple vertebrates first took their tentative steps onto dry land.
或许这些早期动物仍通过 It's probable that these early animals were moving around
类似鳍的东西行走 using something that was still pretty much like the fins
就像以前它们在水里一样 that they used to get around in the water.
那从水里迈上陆地的一小步 With that one small step from water to dry land...
却彻底改变了地球上的生物 life on earth changed forever.