新奇事件簿 科学家发现了世界上最干净的空气

Scientists have discovered what they believe to be the cleanest air on Earth. Researchers from Colorado State University and the Australian Bureau of Meteorology conducted research on the purity of the air above Antarctica. They found a region over the Southern Ocean, between the south of Australia and Antarctica, that was "unaffected" by human activity. The scientists said the area they researched formed the atmosphere in the lower clouds. The analysis of the air showed that it was totally free from "anthropogenic aerosols²". These are pollutants³ or particles derived⁴ from human activity, or dust from other continents. The scientists called this pollution-free area, "truly pristine⁵".

The scientists analysed the structure of airborne microbes in the lower clouds over the Southern Ocean. They looked at the DNA⁶ of the microbes and tracked where they came from. Their analysis included monitoring wind trajectories⁷ to detect how far the microbes may have travelled. They found that the atmospheric⁸ eco-system was very much "isolated," self-contained, and free from contaminants from elsewhere in the world. The source of the microbes was the Southern Ocean, rather than airborne pollutants from other continents. The researchers concluded that the Southern Ocean is one of very few places on Earth that has been "minimally⁹ affected¹ by anthropogenic activities".

科学家发现了他们认为是地球上最干净的空气。来自科罗拉多州立大学和澳大利亚气象局的研究人员对南极洲上空空气的纯净度进行了研究。他们发现，在澳大利亚南部和南极洲之间的南大洋上空有一块未受人类活动影响的区域。科学家们表示，他们研究的这片区域在较低云层中形成了大气层。对空气的分析表明，空气中完全没有“人为气溶胶”。这些污染物或颗粒来自人类活动或其他大陆上的灰尘。科学家将这片无污染区域为“真正的原始”。

科学家们分析了南大洋上空较低云层中空气微生物的结构。他们观察了微生物的DNA并追踪它们的来源。他们的分析包括监测风的轨迹，以检测微生物的传播距离。他们发现其大气生态系统非常“孤立”、独立，且没有来自世界其他地方的污染物。这些微生物来自南大洋，而不是其他大陆上的空气污染物。研究人员得出结论，南大洋是地球上为数不多的几个“受人为活动影响最小”的地方之一。

1 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

2 aerosols   

n.气溶胶( aerosol的名词复数 )；喷雾剂；（气体中的）浮粒；喷雾器

参考例句：

• Aerosols are present throughout the atmosphere. 气溶胶存在于整个大气层。 来自辞典例句
• Deodorants are available as aerosols or roll-ons. 除臭剂有喷雾装或滚抹装。 来自辞典例句

3 pollutants   

污染物质（尤指工业废物）( pollutant的名词复数 )

参考例句：

• Pollutants are constantly being released into the atmosphere. 污染物质正在不断地被排放到大气中去。
• The 1987 Amendments limit 301(g) discharges to a few well-studied nonconventional pollutants. 1987年的修正案把第301条（g）的普通排放限制施加在一些认真研究过的几种非常规污染物上。 来自英汉非文学 - 环境法 - 环境法

4 derived   

vi.起源；由来；衍生；导出v.得到( derive的过去式和过去分词 )；（从…中）得到获得；源于；（从…中）提取

参考例句：

• Many English words are derived from Latin and Greek. 英语很多词源出于拉丁文和希腊文。 来自《简明英汉词典》
• He derived his enthusiasm for literature from his father. 他对文学的爱好是受他父亲的影响。 来自《简明英汉词典》

5 pristine   

adj.原来的，古时的，原始的，纯净的，无垢的

参考例句：

• He wiped his fingers on his pristine handkerchief.他用他那块洁净的手帕擦手指。
• He wasn't about to blemish that pristine record.他本不想去玷污那清白的过去。

6 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

7 trajectories   

n.弹道( trajectory的名词复数 )；轨道；轨线；常角轨道

参考例句：

• To answer this question, we need to plot trajectories of principal stresses. 为了回答这个问题，我们尚须画出主应力迹线图。 来自辞典例句
• In the space program the theory is used to determine spaceship trajectories. 在空间计划中，这个理论用于确定飞船的轨道。 来自辞典例句

8 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

9 minimally   

最低限度地，最低程度地

参考例句：

• Food spoilage problems occur with minimally processed, concentrated frozen citrus products. 食品的变质也发生在轻微加工的、浓缩冷冻的柑橘制品中。
• So, minimally, they are responsible for such actions and omissions. 所以，至少来说，他们要对这样的行为和忽略负责。