methane gas capture – photo by meaduva (source: Flickr Creative Commons)
A new article in The Ecologist shines a light on methane, the often-ignored greenhouse gas that is produced from both natural and human sources. Methane’s contribution to the greenhouse effect is estimated to be about 18% compared to CO2’s 63%. Yet it is also 20-30 times more potent than CO2 and has only one tenth the atmospheric life span. This means that methane emission reduction could have a significantly more immediate effect on curbing climate change than cutting CO2, which hasn’t happened yet on a global level anyway.
Man made methane emissions can be reduced in among the following ways:
• Better waste disposal and methane capture from landfills
• Changing livestock diets (and human diets by consuming less livestock)
• Better management of rice cultivation
• Capturing methane released from mining
There are a number of ideas within the field of geo-engineering that deal with the problem of excessive naturally produced methane, which is mostly emitted by wetlands. However, none of the ’solutions’ sound that great. For example, sulfur pollution in acid rain actually reduces natural methane production. But then of course you have to make more acid rain.
The uncertainties about biomass and wetlands pale into relative insignificance when it comes to the vast methane reservoirs locked up in Arctic tundra – methane that scientists are convinced was a factor in previous de-glaciations.
–The Ecologist
Methane and carbon are both locked in permafrost in the Arctic regions. If warming temperatures melt the permafrost, this releases vast amounts of carbon and methane into the atmosphere in a short time, thereby theoretically contributing further to the greenhouse effect and global warming/climate change. This creates a positive feedback loop where continued warming causes more greenhouse gas emissions and vice versa.
For a clear explanation of how methane is emitted from wetlands and melting permafrost check out this video by researchers at the University of Alaska Fairbanks. It’s pretty fun in a ’scientific research meets Bevis and Butthead’ kind of way.
Arctic Lake Methane Ignited by Katey Walter Anthony
by Graham Land
Additional resources:
Methane even worse greenhouse gas than we thought
