一直以來我們都很關注大氣汙染、廢棄物汙染，但是卻忽略了一種同樣很危險的汙染——光汙染。科學家指出，世界各地的夜晚都變得越來越亮，如果再持續下去，我們將很快看不到美麗的星空。
The world’s nights are getting alarmingly brighter – bad news for all sorts of creatures, humans included – as light pollution encroaches on darkness almost everywhere.地球的夜晚變得越來越亮，這種明亮讓人不安——事實上，這對於包括人類在內的各種生物都是壞消息——因為光汙染正在一點一點地蠶食掉各個角落的黑暗。
什麼是光汙染？
光汙染是繼廢氣、廢水、廢渣和噪聲等汙染之後的一種新的環境汙染源，主要包括白亮汙染、人工白晝汙染和彩光汙染。
Satellite observations made by researchers during five consecutive Octobers show Earth’s artificially lit outdoor area grew by 2% a year from 2012 to 2016. So did nighttime brightness.研究人員連續五年在十月份觀測到的衛星數據顯示，2012年到2016年間，地球上有人工照明的室外面積每年增加2%，夜間亮度也隨之增加。
Light pollution was even worse than that, according to the German-led team, because the sensor used cannot detect some of the LED lighting that is becoming more widespread, specifically blue light.由德國科學家帶領的這一研究團隊指出，光汙染實際上比數據顯示的更糟，因為衛星無法探測到一些LED照明燈，尤其是藍光，發出的光線。如今人們對LED照明的應用日益普遍。
The observations indicate stable levels of night light in the US, the Netherlands, Spain and Italy. But light pollution is almost certainly on the rise in those countries given this elusive blue light, according to Christopher Kyba of the GFZ German research centre for geosciences and the lead author of the study published in Science Advances.觀測結果顯示，美國、荷蘭、西班牙和義大利的夜間亮度保持穩定。但是，該研究的第一作者、德國地學研究中心的克裡斯多夫凱巴稱，考慮到觀測不到的藍光，基本上可以肯定這些國家的光汙染有所增加。這項研究發表在《科學進展》上。
Also on the rise is the spread of light into the hinterlands and overall increased use. The findings shatter the long-held notion that more energy-efficient lighting would decrease usage on the global – or at least a national – scale.與此同時，偏僻落後地區的夜間亮度也在上升，夜間照明使用量總體增加。這一研究發現粉碎了長期以來人們持有的一個觀點，就是引進更節能的照明系統會減少全球——至少是全國範圍內的——照明使用量。
「Honestly, I had thought and assumed and hoped that with LEDs we were turning the corner. There’s also a lot more awareness of light pollution,」 Kyba told reporters by phone from Potsdam. 「It is quite disappointing.」「說實話，我原來的設想和希望是，有了LED照明系統，事情會有所轉機。人們對光汙染的意識會大大增強，」凱巴通過電話告訴德國波茨坦的記者說，「結果挺讓人失望的。」
The biological impact from surging artificial light is also significant, according to the researchers.研究人員表示，人工照明激增也給生物造成了重大影響。
People’s sleep can be marred, which in turn can affect their health. The migration and reproduction of birds, fish, amphibians, insects and bats can be disrupted. Plants can have abnormally extended growing periods. And forget about seeing stars or the Milky Way if the trend continues.人們的睡眠質量會受到損害，從而影響到身體健康。鳥類、魚類、兩棲動物、昆蟲、蝙蝠的遷徙和繁衍也會被打亂。植物的生長期會異常地延長。如果光汙染持續惡化，你再也別想看到星空或銀河了。
具體而言，光汙染對人的身體會造成哪些危害呢？
1. 光汙染會嚴重損害人們的眼睛，導致各種眼疾。螢光燈的頻繁閃爍會迫使瞳孔頻繁縮放，造成眼部疲勞。如果長時間受強光刺激，會導致視網膜水腫、模糊，嚴重的會破壞視網膜上的感光細胞，甚至使視力受到影響。光照越強，時間越長，對眼睛的刺激就越大。衛生專家認為，視覺環境是形成近視的主要原因，而不是用眼習慣。
2. 光汙染可誘發癌症。2008年一項針對以色列的調查研究發現，光汙染越嚴重的地方，婦女罹患乳腺癌的機率大大增加。原因可能是非自然光抑制了人體的免疫系統，影響激素的產生，內分泌平衡遭破壞而導致癌變。
3. 光汙染會讓人產生不利情緒。光汙染可能會引起頭痛、疲勞、性能力下降，增加壓力和焦慮。
About the only places with dramatic declines in night light were in areas of conflict such as Syria and Yemen, the researchers found. Australia also reported a noticeable drop, but that was because wildfires were raging early in the study. Researchers were unable to filter out the bright burning light.研究人員發現，夜間亮度下降的唯一地區是敘利亞和葉門這樣的戰亂國家。根據觀測報告，澳大利亞也出現了夜間亮度的明顯下降，但那是因為研究早期澳大利亞發生了大火災，研究人員無法將野火的亮度過濾掉。
Asia, Africa and South America, for the most part, saw a surge in artificial night lighting.在亞洲、非洲和南美洲的大部分地區，夜間人工照明水平都在迅速上升。
More and more places are installing outdoor lighting, given its low cost and the overall growth in communities』 wealth, the scientists noted. Urban sprawl is also moving towns farther out. The outskirts of major cities in developing nations were brightening quite rapidly, Kyba said.科學家指出，因為照明成本低，加上社會財富總體水平提高，越來越多的地區安裝了室外照明系統。城市擴張也讓村鎮不停向外延伸。凱巴說，發展中國家大城市郊區的夜間亮度正在迅速上升。
Other especially bright hot spots included sprawling greenhouses in the Netherlands and areas of intensive agriculture.其他特別亮的區域包括荷蘭四處蔓延的溫室和開展集約化農業生產的土地。
One of the co-authors, Franz Holker of the Leibniz institute of freshwater ecology and inland fisheries in Berlin, said things were at the critical point.該研究的作者之一、柏林萊布尼茲淡水生態學和內陸漁業研究所的弗蘭茨霍爾克表示，事態發展已經到了危急關頭。
「Many people are using light at night without really thinking about the cost,」 Holker said. Not just the economic cost, 「but also the cost that you have to pay from an ecological, environmental perspective」.霍爾克說：「很多人在晚上隨便開燈，從未認真考慮過代價。」不只是經濟代價，「還有生態、環境所必須付出的代價」。
Kyba and his colleagues recommend avoiding glaring lamps whenever possible – choosing amber over so-called white LEDs – and using more efficient ways to illuminate places such as parking lots or city streets.凱巴和他的同事建議儘量避免耀眼的檯燈，選擇琥珀燈而不是所謂的LED白光燈，用更高效的方式來給停車場或城市街道等地方照明。
For example, dim, closely spaced lights tend to provide better visibility than bright lights that are more spread out.比如，昏暗而集中的光線比明亮而分散的光線能提供更好的可見度。
為了自己的健康，為了地球上的生物，為了燦爛的星空，請少開幾盞燈，拒絕光汙染。
英文來源：衛報翻譯&編輯：丹妮