Science Daily: For years scientists have intensely argued over whether increases of potent methane gas concentrations in the atmosphere - from about 5,000 years ago to the start of the industrial revolution - were triggered by natural causes or human activities.
A new study, which will be published Friday in the journal Science, suggests the increase in methane likely was caused by both.
Lead author Logan Mitchell, who coordinated the research as a doctoral student at Oregon State University, said the "early...