Methane is a particularly potent greenhouse gas and the science behind this, to say the least, is solid. Yes, according to these figures there will be a net cost of about $1.7 billion. Can we easily quantify the costs of climate change? No, because this is very complex, but we do know that we need to keep global warming below 1.5 C to avoid a truly catastrophic situation that would endanger human civilisation as we know it. (Just think of the costs of relocating people from low-lying cities as ocean levels rise, to give a concrete example.) Given methane's potent effects, it is clear this should be done... and perhaps even more needs to be done.