VOA慢速英语2014 地球臭氧层出现恢复迹象

 

Earth's Ozone¹ Layer Shows Signs of Recovery 地球臭氧层出现恢复迹象

The new report says the Earth’s ozone layer is showing signs of recovery. 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. But near Earth, ozone is a common pollutant². It can harm people, crops and other plants.

The UN report says the ozone layer appears to be improving because of a reduction of industrial chemicals into the air.

Scientists say the improving conditions are a result of an international treaty signed in 1987. It is called the Montreal Protocol³.

The Montreal Protocol was meant to end the use of or sharply reduce over 100 known ozone depleting⁴ substances. It banned ozone-depleting chemicals, including man-made chlorofluorocarbons, also known as CFCs. They were once widely used in refrigerators, spray cans, insulation⁵ foam⁶ and fire suppression products.

The report comes as good news for Geir Braathen, a scientific officer with the World Meteorological Organization. He says a lot has changed for the better since the UN agency released its last report on ozone depletion⁷ four years ago. 

“Now for the first time in this report, we say that we see indications of a small increase in total ozone.  So that means that recovery of the ozone layer in terms of total ozone has just started.  If you go more specifically at the higher level, about 40 kilometers in the stratosphere high above the ground, there one sees a clear increase in ozone in recent years.”

Geir Braathen says this is a sign that the amount of ozone-depleting gases is decreasing and ozone levels are on the way up again. The stratospheric ozone layer is a fragile shield of gas. It protects the Earth from harmful ultraviolet radiation.

The UN Environment Program says the Montreal Protocol will prevent two million cases of skin cancer each year by 2030. Officials say it will also help prevent damage to human eyes and immune systems, which protect the body against disease.

The report finds the discontinuation of ozone-depleting substances has been good for the world climate. This is because many of these substances also are strong greenhouse gases -- pollution linked to climate change. But the report shows that some substitutes are themselves strong greenhouse gases that could harm these gains.

The WMO calls international action on the ozone layer a major environment success story. It is urging the same kind of unity⁸ to tackle the even greater issue of climate change.

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 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。

3 protocol   

n.议定书，草约，会谈记录，外交礼节

参考例句：

• We must observe the correct protocol.我们必须遵守应有的礼仪。
• The statesmen signed a protocol.那些政治家签了议定书。

4 depleting   

使大大的减少，使空虚( deplete的现在分词 )； 耗尽，使枯竭

参考例句：

• Regulations are outlawing certain refrigerants, such as chlorofluorocarbons, which contain ozone-depleting chemicals. 随后出台的政策禁用了部分制冷剂，如破坏臭氧层的氟氯碳化合物。
• Aging, being a series of continual losses, can be keenly depleting. 老龄化，作为一个系列的连续亏损，可以清楚地消耗。

5 insulation   

n.隔离；绝缘；隔热

参考例句：

• Please examine the insulation of the electric wires in my house.请检查一下我屋子里电线的绝缘情况。
• It is always difficult to assure good insulation between the electric leads.要保证两个电触头之间有良好的绝缘总是很困难的。

6 foam   

v./n.泡沫，起泡沫

参考例句：

• The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
• The surface of the water is full of foam.水面都是泡沫。

7 depletion   

n.耗尽，枯竭

参考例句：

• Increased consumption of water has led to rapid depletion of groundwater reserves.用水量的增加导致了地下水贮备迅速枯竭。
• Farmers should rotate crops every season to prevent depletion of the soil.农夫每季应该要轮耕，以免耗尽土壤。

8 unity   

n.团结，联合，统一；和睦，协调

参考例句：

• When we speak of unity,we do not mean unprincipled peace.所谓团结，并非一团和气。
• We must strengthen our unity in the face of powerful enemies.大敌当前，我们必须加强团结。