Over 20 years it traps 84x times as much heat and 28x over 100 years. I believe most EPA calculations use the 100 year timescale. So if there's 4% leakage (th

Over 20 years it traps 84x times as much heat and 28x over 100 years. I believe most EPA calculations use the 100 year timescale. So if there's 4% leakage (there are some fields that exceed this) its worse than coal on 100 year timescale. Its arguable what the correct timescale to consider it is. Personally I think 100 years is too long given methane's potential feedback effects. IE, warming causes methane to be released from Arctic tundra melt causing more warming, etc. And there's also the issue that the higher the concentration of methane in the atmosphere the longer it takes to decay.