A giant mirror drifts slowly through space between the earth’s surface and the sun, intercepting the rays of sunlight before they reach the earth and deflecting them safely away.
在地球表面与太阳之间的太空中,一面巨大的镜子缓缓地飘动 着，把尚未抵达地球的光线拦截住并安全地反射到别处。
The mirror, made of millions of silicon chips, is situated at a point in space where the sun’s gravity and the earth’s cancel each other out.
这面镜子由数百万硅片组成,在其所处空间位置上，太阳与地 球对它的引力刚好相互抵消。
This vast structure, assembled painstakingly for years by spacecraft, drifts naturally away from its starting point over time, but complex on-board systems nudge it gradually back to resume its vital role in keeping us safe.
这一庞大的装置由宇宙飞船历经数年精心装配而成,经过一段 时间后,它会很自然地飘离最初的位置,但复杂的内部系统会令其逐 渐飘回原位，以使其继续担负起保障我们安全的重要使命。
This space mirror would cost hundreds of billions of dollars, even if it were technically feasible. But many scientists say we may need to start building space mirrors, creating artificial clouds, or altering the chemistry of the sea to prevent the worst effects of global warming.
迄今为止,这面太空镜即使技术上可行,其造价也将髙达数千亿 美元。但许多科学家表示,为预防全球变暖的最坏影响,我们可能很 快就需要着手建造太空镜,制造人造云，或者改变海洋的化学成分。
Climate change is occurring faster than predicted and the risks are growing day by day. Altering the earth’s systems to help cool the planet may soon be the only option, many scientists believe, as our runaway appetite for fossil fuels overtakes our good intentions on emissions.
气候变化的速度比人们预想的要快,所产生的危险后果也与日 俱增。许多科学家认为，由于我们对矿物燃料无限膨胀的欲望压倒 了减排的良好初衷,改变地球的自然系统可能很快就会成为帮助这 颗行星降温的唯一途径。
“The chances of reducing emissions fast enough now are very low,” said Stephen Salter, professor of engineering design at Edinburgh University. “This is a jolly strong reason to look at alternatives.”
爱丁堡大学工程设计学教授斯蒂芬_索尔特表示眼下，及时 减排的可能性非常低,这为考虑其他方法提供了非常充分的理由。”
The science of altering the world’s natural systems is called geo-engineering. Once on the whacky fringes of scientific research, the subject is rapidly becoming mainstream. John Holdren, chief scientific adviser to US president Barack Obama, said in public: “It’s got to be looked at.. . We don’t have the luxury of ruling [out] any approach.”
改变地球自然系统的学科被称为“地球工程学”。这门学科曾被 视为想法诡异的边缘科研领域,如今却正迅速成为主流。美国总统巴 拉克.奥巴马的首席科学顾问约翰?霍尔德伦曾公开表示必须对这门学科加以考虑……我们没有轻松到可以把哪条途径排除(在外)。”
The debate has been intensified by a set of studies published in the journal Nature. They concluded the world had little chance of holding temperature rises to 2°Ca level widely regarded by scientists as the limit of safety, beyond which climate change becomes irreversible and potentially catastrophic. Such a level of warming risks leading, for example, to the melting of permafrost in Siberia, so releasing large quantities of methane, and in turn causing stronger and more rapid warming.
《自然》期刊中发表的一系列研究令争论进一步升级。这些研究得出的结论是，把气温升幅控 制在2摄氏度以内的可能性微乎其微。科学家普遍把2摄氏度视为安全限度。超出此限度，气候变化 将变得不可逆转，并可能导致灾难性后果:包括令西伯利亚永久冻结带融化，由此释放出的大量甲 烧气体反过来又将导致更强烈、更迅速的升温。
Besides the giant mirror approach, scientists are also exploring removing carbon from the atmosphere.
除了在太空中装太阳镜，科学家还在探索如何清除大气层中的碳元素。
One way is to fertilize the oceans with iron, so plankton grows and absorbs carbon.
方法之一是向海水中加人铁元素，促进浮游生物生长并吸收碳元素。
Less realistic are enormous air “scrubbers”~banks of sails coated with chemicals that react with C02. Two unsolved problems are mastering the chemical absorption and the sheer amount of energy that would be needed to propel vast volumes of air.
另一种不那么现实的方法是，把可与二氧化碳发生反应的化学制剂涂抹在船帆上，使其排列 成行，形成巨大的空气“洗涤塔”。两个有待解决的问题是，如何控制化学吸收，如何提供推动大量 空气所需的巨大能量。
Employing geo-engineering would not remove the need for deep emissions cuts，Prof Salter warned: “No one in geo-engineering would argue that.” The two must be pursued in tandem, or rising emissions would counteract the benefits of the earth-altering projects.
即便运用地球工程学，仍然需要大幅减排,索尔特教授警告称：“地球工程学界的所有人士都会 认同这一点。”两方面的努力必须步调一致，否则，日益增加的排放量将抵消“改天换地”带来的裨益。
Tim Lenton, professor of earth system science at the University of East Anglia, who conducted a review of geo-engineering methods, said scientists must beware of “tinkering with a system you do not fully understand”. For instance, he said, studies showed that putting sulphate aerosols into the atmosphere caused drying in vulnerable regions.
东安格利亚大学地球系统科学教授蒂姆?兰登曾对地球工程学方法进行过评述。他表示,科 学家必须谨防“对一个不十分了解的系统进行随意改动。”他举例称,研究显示，在大气层投放硫酸 盐气溶胶，会导致环境脆弱地区干旱。
Apparently, the consequences of ignoring the green house effects are dire. Before the giant mirror could be hung up in space or a better idea has been hatched, we，d better be cautious and try to reduce the green house gas.
很明显，忽视温室效应的后果是很可怕的。所以在太空里挂起太阳镜或科学家们想出更好的 主意前，我们还是尽量留心，减少温室气体的排放吧。