A potent, explosive greenhouse gas, methane is the simplest of all alkanes, and is the main component of natural gas, which is burned for heat and energy production all over the world. One of the most abundant organic compounds locked within the planet, it is rapidly finding its way up and out into our atmosphere, where it accumulates and accelerates global warming.
Where Methane Comes From
Methane comes from a variety of sources, and while you might have heard that cattle and other ruminant animals produce it as a byproduct of their digestive process, you might not know that so-called cattle belch alone is responsible for an astounding sixteen percent of atmospheric methane. A 2009 study found that about 51% of all global greenhouse gas emissions could be attributed to both the supply chain and life cycle of various livestock products including those sourced from cattle, pigs, and chickens, with 37% of methane coming from these sources. The study took manufacture and transportation into account to come to these figures, meaning that if you are going to use animal products, using those produced close to home can affect your own carbon footprint significantly, just as choosing locally grown produce can.
In addition, methane is released into the atmosphere when natural gas is burned, and it is also emitted as a byproduct of coal mining, although processes such as coal bed methane extraction and enhanced coal bed methane recovery can mitigate it somewhat.
Methane is also released as a byproduct of the decay of organic matter; sedimentary deposits often contain a high volume of the gas, and microorganisms produce it via the process of methanogenesis, which is a form of anaerobic respiration. A good example of this process is the breakdown of organic substances at landfills. In some cases, landfill operators are collecting methane produced via this process as biofuel.
Methane and Global Warming
In 2010, scientists measured methane levels in the atmosphere over the Arctic at a level twice as high as that found at any time over the preceding 400,000 years. Its potential for acting as a catalyst to global warming is high – when compared with a carbon dioxide emission of the same mass, a methane emission has 25 times the warming effect. While carbon dioxide is a major concern due to its lengthy lifespan of more than 100 years, methane dissipates after just 8.4 years in the atmosphere.
Since 1750, the earth’s atmospheric methane concentration has increased by an estimated one hundred fifty percent. Since there are vast amounts of methane hidden within permafrost, and since increased warming comes with increased methane release from these sources, it really is something which needs to be approached mindfully. All global warming is a major concern for the oceans, marine, life, and humanity – not to mention the rest of the life that this planet holds. Despite the rumblings of naysayers, science has proven that warming is increasing, and along with it, our ability to survive and thrive is decreasing. The good news, though, is that with conscientious effort, we can turn the global warming ship around. Do your part by ensuring you make the most responsible choices possible.