Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks.

甲烷（CH4）是大气中仅次于CO2对全球变暖贡献第二大的温室气体，全球大气CH4的收支取决于CH4的源与汇。

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This gets us one step closer to a global picture of carbon sources and sinks.

BBC: How Earth's land is used