VOA慢速英语--科学家列出四种捕获碳的方法 限制气温上升

Scientists List Four Ways to Capture Carbon, Limit Rising Temperatures

A new report suggests four simple ways to remove carbon dioxide from the atmosphere.

Carbon dioxide is among the gases linked to the increase in the Earth’s temperature.

The National Academies of Sciences, Engineering and Medicine published the report.

All four methods to take carbon from the air and store it use natural processes.

However, all of them still would not be enough to prevent possible catastrophic levels of climate change, the report said.

Climate scientists say carbon emissions² from burning fossil³ fuels have warmed the Earth’s atmosphere by about 1 degree. At the current rate, temperatures will likely increase by 1.5 degrees by 2050. That warning is from a new report by the United Nations Intergovernmental Panel⁴ on Climate Change.

Technologies that create no emissions, like wind or solar power, will not be enough to stop climate change, the U.N. report said. It called for technologies that take carbon dioxide out of the air.

The group of experts with the National Academies of Sciences considered existing methods for removing carbon dioxide from the atmosphere.

The first of the four is one that almost everyone knows already: planting trees.

It’s not really a technology, admitted Princeton University biologist Stephen Pacala. He headed the group of scientists.

The second method is also simple: take better care of existing forests. These are the two least costly⁵ ways to get large amounts of carbon out of the air, the report said.

Farms offer the next biggest and least costly carbon dioxide removal method.

Soil that is used to grow crops too much loses carbon and nutrients⁶. Rebuilding the soil increases its ability to hold water and makes it more fertile.

The carbon comes from the atmosphere," Pacala said, and he added, "We know how to do quite a bit of this."

The fourth method, the report said, is known as biomass energy with carbon capture and storage, or BECCS. BECCS involves burning some kind of plant matter to produce electricity, fuel or heat, then capturing and storing the carbon gasses in underground containers.

The report said BECCS could remove the largest amount of carbon dioxide from the air, but is also the most costly.

If used worldwide, these four techniques could remove up to 10 gigatons of carbon dioxide from the atmosphere each year.

It is estimated that 50 gigatons of carbon are produced each year around the world.

The scientists said that using more land for carbon dioxide removal would mean taking land needed to produce crops.

The scientists also considered new technologies that capture carbon dioxide from the air.

For example, one method would use the ability of some naturally existing minerals that react with carbon dioxide to store it. But the scientists said this method is not well understood.

I’m Susan Shand.

Words in This Story

atmosphere – n. the whole mass of air that surrounds the Eart

catastrophic – adj. a terrible disaster

emission¹ – n producing or sending out something (such as energy or gas) from a source

fossil fuels – n. a fuel such as coal, oil, or natural gas that is formed in the earth from dead plants or animals

biomass – n. organic matter used as a fuel, especially in a power station for the generation of electricity.

gigaton – n. a unit of explosive force equal to one billion tons of TNT

1 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。

2 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。

3 fossil   

n.化石，食古不化的人，老顽固

参考例句：

• At this distance of time it is difficult to date the fossil.时间隔得这么久了，很难确定这化石的年代。
• The man is a fossil.那人是个老顽固。

4 panel   

n.面，板，专门小组，控制板，仪表盘

参考例句：

• The unusual control panel on the walls caught our attention.墙上不同寻常的控制板引起了我们的注意。
• The panel of judges included several well-known writers.评判小组中包括几位知名作家。

5 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

6 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》