Global natural and anthropogenic methane emissions with approaches, potentials, economic costs, and social benefits of reductions: Review and outlook.

The increase in atmospheric methane (CH) level directly contributes to approximately one-fifth of global mean temperature rise since preindustrial era, only next to CO. Global anthropogenic CH emissions has augmented by nearly three-fifths during the past five decades; due to climate change, natural CH emissions are plausibly projected to increase in the foreseeable future. Thereby, examining and projecting long-term natural and anthropogenic CH emissions and sinks are imperative. According to peer-reviewed literatures as information sources for this compendium, we recapitulate natural and anthropogenic CH emissions, summarize available abatement approaches and their mitigation potentials, and investigate and encapsulate economic costs and social benefits of reductions. We list current challenges in realizing CH emissions reductions and suggest possible technical pathways for future mitigation.