Methane (CH4) is the primary component of natural gas, a gas we all know. We use it for heating our homes. It is a fossil fuel, like oil and coal, and is part of our carbon-driven economy. When we ‘use’ methane it means we ‘burn’ or ‘oxidise’ it.
So far so bad – but the big problem is not the methane we burn. The big problem is the methane we don’t burn. If methane gets into the atmosphere, it is much worse than CO2.
Methane gets into the atmosphere in both natural as well as man-made ways. The oil & gas industry leaks it, cows belch it, and the permafrost grounds in Siberia release it when they thaw(1). That’s just 3 big sources of methane in the air, there are more. Please refer to The Global Carbon Project for more information.
The problem of atmospheric methane is that it has an initial global warming potential (GWP) 120 times worse than CO2 (2). 40% of all current global warming (GW) is caused by methane, and the problem / the proportion of methane is growing. (3)
Today’s atmosphere contains around 1.9 parts per million of methane. (ppm = parts per million. To visualize one part per million, think of one cubic centimeter in one cubic meter.)
In pre-industrial times, i.e. in the 1850’s, there was only roughly 0.7 ppm of methane in the atmosphere, which means we have increased it by a factor of 2.5. This man-made increase is responsible for 20-30% of global warming. Nowaday’s yearly global temperature increase is caused by (mainly) methane and CO2 in around equal portions (11). All in all we (AMR) quote methane’s portion of GW as being 40%.
Methane is a natural component of the atmosphere. Earth always had a ‘methane problem’ and nature has always dealt with it. Unlike atmospheric CO2, which enables photosynthesis, atmospheric methane has no beneficial effect – life on earth could happen with zero methane in the air. But it is both undesirable and impossible to remove all methane from the atmosphere – the sustainable goal would be to return to pre-industrial levels.
Continue to Enhanced Atmospheric Methane Oxidation