Previously unknown methane sources identified in Hamburg

After carbon dioxide, methane is the second most common greenhouse gas caused by human activity. Moreover, over a 20-year period, its global warming potential is more than 80 times that of carbon dioxide. The largest known sources are wetland, agriculture and waste, and fossil fuel production and use. Methane has a much shorter atmospheric lifetime than CO2 (around 12 years compared with centuries for CO2). Consequently, the reduction of methane emissions has considerable potential for limiting global warming in the short to medium term.