(1)Springtime Ozone Loss

                        25 大气层中臭氧正日渐稀薄

DATE=3-21-01
TITLE=SCIENCE REPORT - (1)Springtime Ozone¹ Loss
BYLINE=George Grow

(Start at 1'00")This is the VOA Special English SCIENCE REPORT.
Information gathered one year ago shows large areas of Earth's lower (2)atmosphere with very little ozone over northern Canada. (3)Instruments on airplanes (4)measured the ozone loss over Hudson Bay, Baffin Bay and parts of the Arctic² Ocean.
Scientists say the measurements were the first to confirm (5)ozone loss over large areas just south of the (6)Arctic Circle. They say the lack of surface ozone has been observed each spring since the Nineteen-Eighties at a research station in northern Canada.
Scientists from the National Center for Atmospheric³ Research led the experiment. University researchers and the American space agency NASA (7)assisted with the project.
Ozone is a form of oxygen. It is found in the air we breathe and in Earth's atmosphere. The ozone layer in the upper atmosphere protects life on Earth. The ozone there blocks harmful radiation from the sun. Near Earth, ozone is a common pollutant⁴. It can harm people, crops and other plants.
Having less ozone near the surface of the Earth may sound like a good thing. However, scientists are concerned. Although ozone is a pollutant, it also produces a chemical that removes pollutants⁵ from the atmosphere.
Brian Ridley was involved on the research flights last year. He says the ozone losses over the Arctic are not threatening. He says they show that scientists still have a lot to learn about the chemistry of the atmosphere.
Last April, one research airplane flew almost seven-hundred-forty kilometers through an area over Hudson Bay with little or no ozone. Ozone levels in most areas in the northern part of the world are normally thirty to forty-five parts per one-thousand-million. Over Hudson Bay, the ozone levels dropped to less than one part per one-thousand-million. Scientists (8)suspect the ozone loss ends quickly with the arrival of ozone-rich air from other areas.
Scientists say surface ozone loss happens during the spring when (9)sunlight returns to the Arctic. This starts chemical (10)processes that do not happen during the dark winter months.
Scientists say a possible cause of ozone destruction is the chemical (11)bromine. Satellites orbiting Earth have measured large amounts of bromine high in the atmosphere. But scientists do not know what starts and continues bromine production through the spring.
This VOA Special English SCIENCE REPORT was written by George Grow.

(1)  springtime[5sprINtaIm]n.春天, 春季
(2)  atmosphere[ 5AtmEsfiE ]n.大气, 空气, 气氛
(3) instrument[ 5instrumEnt ]n.工具, 手段, 器械, 器具, 手段
(4) measured[ 5meVEd ]adj.标准的, 整齐的, 有规则的
(5) ozone[ 5EuzEun, Eu5z- ]n.新鲜的空气, [化]臭氧
(6) Arctic Circle n. 北极圈
(7) assist[ E5sist ]v.援助, 帮助
(8) suspect[ sEs5pekt ]n.嫌疑犯adj.令人怀疑的, 不可信的, 可疑的
(9) sunlight[ 5sQnlait ]n.日光, 阳光, 日照
(10) process[ prE5ses ]n.过程, 作用, 方法, 程序, 步骤, 进行, 推移vt.加工, 处理
(11) bromine[ 5brEumi:n ]n.[化]溴

1 ozone   

n.臭氧，新鲜空气

参考例句：

• The ozone layer is a protective layer around the planet Earth.臭氧层是地球的保护层。
• The capacity of ozone can adjust according of requirement.臭氧的产量可根据需要或调节。

2 Arctic   

adj.北极的；n.北极

参考例句：

• They flew over the unlimited reaches of the Arctic.他们飞过了茫茫无边的北极上空。
• The sort of animal lived in the Arctic Circle.这种动物生活在北极圈里。

3 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。

4 pollutant   

n.污染物质，散布污染物质者

参考例句：

• Coal itself is a heavy pollutant.煤本身就是一种严重的污染物。
• Carbon dioxide may not be a typical air pollutant.二氧化碳可能不是一种典型的污染物。

5 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