The atmospheric concentration of methyl chloride (CH 3Cl) is very low, only at 10 -12 (V/V) level.

氯甲烷在大气中的浓度较低，仅为10 -12 级别。

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Now that the gas is no longer being produced, scientists can more accurately gauge the action of hydroxyl upon methyl chloroform's atmospheric concentration.

既然再不会生成这种气体，那么，科学家们就能够更精确地测量在甲醇氯仿物的空气聚合反应中生成的氢化物水平。

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Human activities has result in the increase of atmospheric concentration of greenhouse gases, which is concerned as a main cause of the global climate change.

人类活动造成大气中温室气体浓度急剧增加已成为全球变化中最主要和最直接的变化。

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Since 1960, the atmospheric concentration of carbon dioxide has risen from 310 to 390 parts per million.

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But the actual increase in its atmospheric concentration is a low exponent.

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This measures the amount of warming that can eventually be expected to follow a doubling in the atmospheric concentration of carbon dioxide.

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