The global warming potential of methane (CH4) is about 30 times stronger than that of carbon dioxide (CO2) over a century timescale. Methane emission is hypothesized to have contributed to global climate change events and mass extinctions during Earth’s history. Therefore, the study of CH4 production processes is critically important to the understanding of global climate change. It has been a dogma that biogenic CH4 detectable in the oceans originates exclusively from the anaerobic metabolic activity of methanogenic archaea in hypoxic and anoxic environments, despite reports that many oxic surface and near-surface waters of the world’s oceans are CH4-supersaturated, thereby rendering net sea-to-air emissions of CH4. The phenomenon of CH4 production in oxic marine waters is referred to as the “ocean methane paradox”. Although still not totally resolved, recent studies have generated several hypotheses regarding the sources of CH4 production in oxic seawater. This review will summarize our current understanding of the importance of CH4 in the global climate and analyze the biological processes and their underpinning mechanisms that lead to the production of CH4 in oxic seawater environments. We will also tentatively explore the relationships of these microbial metabolic processes with global changes in climate and environment.

中文翻译：

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气候变化点潜力和不断变化的海洋中甲烷的反常产生

在一个世纪的时间范围内，甲烷（CH4）的全球变暖潜势比二氧化碳（CO2）的强约30倍。甲烷排放被认为是导致地球历史上全球气候变化事件和大规模灭绝的原因。因此，对CH4生产过程的研究对于理解全球气候变化至关重要。尽管有报道说世界上许多有氧表层和近表层水的CH4过饱和，但海洋中可检测到的生物CH4完全源自甲烷化古生菌在低氧和缺氧环境中的厌氧代谢活性，这已成为一条教条。 CH4的海对空气净排放量。在有氧海水中产生CH4的现象被称为“海洋甲烷悖论”。尽管仍未完全解决，但最近的研究产生了一些关于含氧海水中CH4产生来源的假设。这篇综述将总结我们目前对CH4在全球气候中的重要性的理解，并分析导致有氧海水环境中CH4产生的生物过程及其基础机制。我们还将试探这些微生物代谢过程与气候和环境全球变化之间的关系。这篇综述将总结我们目前对CH4在全球气候中的重要性的理解，并分析导致有氧海水环境中CH4产生的生物过程及其基础机制。我们还将试探这些微生物代谢过程与气候和环境全球变化之间的关系。这篇综述将总结我们目前对CH4在全球气候中的重要性的理解，并分析导致有氧海水环境中CH4产生的生物过程及其基础机制。我们还将试探这些微生物代谢过程与气候和环境全球变化之间的关系。