词汇大师-- Saving the World

　　AA: I'm Avi Arditti with Rosanne Skirble, and this week on Wordmaster, our guest is Professor Rob Jackson, director of the Global Change Center at Duke University. He's with us to explain some of the language of ecology and climate change.
RS: And we start with the term "greenhouse gases." These are emissions¹ that trap heat in the atmosphere but, Jackson says, not by definition a bad thing.

　　ROB JACKSON: "Without greenhouse gases, life wouldn't exist; the Earth would be a frozen ball of ice. When they trap extra heat, though, they warm the Earth more than has historically been usual and drive up the Earth's temperature."
RS: "Well, we have three terms that we would like to know more about. One is carbon-neutral. What does it mean to be carbon-neutral?"
ROB JACKSON: "Well, when something is carbon-neutral, it means that the activity has no net greenhouse gas emissions. So, for instance, you might offset³ the fuel that you use by using renewable energy or even by planting trees to offset your emissions. In practice, there are different levels of being carbon-neutral. When you hop⁴ in your car, do you count just the gasoline that you use? Or do you include the fossil fuels that went into making the car or building the roads you drive on? Most people just think about the fuel used."
RS: "And what about your carbon footprint?"
ROB JACKSON: "The term carbon footprint, it's come to mean just the amount of carbon dioxide and other greenhouse gases that come from a given activity, such as driving your car, again. To understand where it comes from, though, you have to know a little environmental history.
"Back in the early nineteen nineties an ecologist named Bill Reese coined the term 'ecological⁵ footprint,' the amount of land needed to support resource use and waste for a given population. So that's where the footprint half of carbon footprint comes from. In common use, through, it's lost the link to land area and just refers to net carbon emissions."
AA: So we have carbon-neutral, carbon footprint and a third term -- carbon sequestration.
ROB JACKSON: "Well, carbon sequestration is the opposite of a carbon emission². So a sequestration activity is something that takes carbon dioxide back out the atmosphere and puts it into wood for trees, for example, or stores it below ground in an aquifer⁶ or in sediments⁷ in the ocean. So you're taking or removing carbon dioxide from the atmosphere."
RS: "On Capitol Hill they're talking about 'cap-and-trade' and 'carbon trading.' What are these terms, what do they mean?"
ROB JACKSON: "A carbon trade or a cap-and-trade works like this: a government or some regulatory body limits the total amount of a pollutant⁸ that enters the atmosphere. So this is what people call the cap.
"The government then issues credits, emissions credits, to the polluters who can sell or trade those credits. That's the term cap-and-trade. And the system works because it rewards companies that reduce pollution by letting them sell their credits for profit."
RS: "And this is something that's popular now in Europe, that's actually in effect in Europe, correct?"
ROB JACKSON: "It's popular in Europe, though, really because it worked here first, not for carbon dioxide but for sulfur⁹. Back in the early nineteen nineties, through the Clean Air Act, we implemented¹⁰ a cap-and-trade system for sulfur emissions in the U.S. and it worked very effectively and very efficiently¹¹ and very quickly to reduce sulfur emissions."
AA: "Acid rain."
ROB JACKSON: "That's correct. So the idea is to take that model and apply it to carbon dioxide and other greenhouse gases. Now it's more complicated with greenhouse gases but the principal is the same. And it really -- it rewards efficiency, it rewards companies financially for reducing their pollution."
RS: "But it's become quite controversial."
AA: "Right. That's right, there have been news reports recently that it's not quite as clear-cut as it might seem."
ROB JACKSON: "Well, it's controversial for many reasons. It's controversial in how the emissions credits are given out, so who gets how many credits, how much a company pays for them. It's also controversial because you have to be careful that the carbon dioxide or the greenhouse gas that you're saving through your system isn't being re-emitted somewhere else.
"So, in other words, if one country sets up a cap-and-trade system to reduce its emissions, but all it does is shunt some activity to another country, and that carbon dioxide ends up in the atmosphere, you really haven't saved anything on a net global basis. It really points out the need for an international system."
AA: "And are there terms that you use to describe a situation like that?"
ROB JACKSON: "A cap-and-trade situation?"
AA: "Or shunting off of -- passing the buck¹² or something, or passing the carbon. I don't know what you would call it."
ROB JACKSON: "Yeah, there is a technical term for it. It's called 'leakage,' and it sounds like your bathtub's leaking or something. But the idea is that use of some activity slides off to some other location or to some other time that's outside the bounds of your system, and therefore you're sort of losing track of it, you're not accounting¹³ for it, and that's why the term leaking is used."
RS: We'll talk more about eco-language next week with Rob Jackson, a professor of biology and environmental sciences at Duke University in Durham, North Carolina.
AA: And that's Wordmaster for this week. You can learn more about English at our Web site, voanews.com/wordmaster. And our e-mail address is [email protected]. With Rosanne Skirble, I'm Avi Arditti.

1 emissions   

排放物( emission的名词复数 )； 散发物（尤指气体）

参考例句：

• Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
• Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。

2 emission   

n.发出物，散发物；发出，散发

参考例句：

• Rigorous measures will be taken to reduce the total pollutant emission.采取严格有力措施，降低污染物排放总量。
• Finally,the way to effectively control particulate emission is pointed out.最后，指出有效降低颗粒排放的方向。

3 offset   

n.分支，补偿；v.抵消，补偿

参考例句：

• Their wage increases would be offset by higher prices.他们增加的工资会被物价上涨所抵消。
• He put up his prices to offset the increased cost of materials.他提高了售价以补偿材料成本的增加。

4 hop   

n.单脚跳，跳跃；vi.单脚跳，跳跃；着手做某事；vt.跳跃，跃过

参考例句：

• The children had a competition to see who could hop the fastest.孩子们举行比赛，看谁单足跳跃最快。
• How long can you hop on your right foot?你用右脚能跳多远？

5 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.

6 aquifer   

n.含水土层

参考例句：

• An aquifer is a water-bearing rock stratum such as sandstone and chalk.地下蓄水层是一些有水的岩石层，如沙岩和白垩岩。
• The wine region's first water came from an ancient aquifer.用来灌溉这个地区葡萄园的第一批水来自古老的地下蓄水层。

7 sediments   

沉淀物( sediment的名词复数 )； 沉积物

参考例句：

• When deposited, 70-80% of the volume of muddy sediments may be water. 泥质沉积物沉积后，体积的70-80％是水。
• Oligocene erosion had truncated the sediments draped over the dome. 覆盖于穹丘上的沉积岩为渐新世侵蚀所截削。

8 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。

9 sulfur   

n.硫，硫磺（=sulphur）

参考例句：

• Sulfur emissions from steel mills become acid rain.炼钢厂排放出的硫形成了酸雨。
• Burning may produce sulfur oxides.燃烧可能会产生硫氧化物。

10 implemented   

v.实现( implement的过去式和过去分词 )；执行；贯彻；使生效

参考例句：

• This agreement, if not implemented, is a mere scrap of paper. 这个协定如不执行只不过是一纸空文。 来自《现代汉英综合大词典》
• The economy is in danger of collapse unless far-reaching reforms are implemented. 如果不实施影响深远的改革，经济就面临崩溃的危险。 来自辞典例句

11 efficiently   

adv.高效率地，有能力地

参考例句：

• The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
• Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。

12 buck   

n.雄鹿，雄兔；v.马离地跳跃

参考例句：

• The boy bent curiously to the skeleton of the buck.这个男孩好奇地弯下身去看鹿的骸骨。
• The female deer attracts the buck with high-pitched sounds.雌鹿以尖声吸引雄鹿。

13 accounting   

n.会计，会计学，借贷对照表

参考例句：

• A job fell vacant in the accounting department.财会部出现了一个空缺。
• There's an accounting error in this entry.这笔账目里有差错。