http://www.bbc.com/news/science-environment-38285300


"Scientists say they are concerned at the rate at which methane in the atmosphere is now rising.

After a period of relative stagnation in the 2000s, the concentration of the gas has surged.

Methane (CH4) is a smaller component than carbon dioxide (CO2) but drives a more potent greenhouse effect.

Researchers warn that efforts to tackle climate change will be undermined unless CH4 is also brought under tighter control. "