The ‘silent’ sources of greenhouse gases and their intriguing solutions

To those who reached their climate change news saturation level during December’s United Nations conference in Copenhagen, I offer a semi-respite. Or, a momentary evasion of the all-too familiar subjects like coal-fired electricity generation and the oil-fired transportation sector. I won’t delve further into the micro-analyzed political intricacies that made Copenhagen what it was and, more importantly, what it wasn’t – a solution, either.

Instead, I would like to turn my lens onto the surprisingly significant emitters of greenhouse gases (GHGs) that casual observers rarely hear of – namely cows, soil, garbage and concrete - and the fascinating technologies that may serve as remedies.

Today most people are aware, that burning coal to produce electricity, oil and gas to produce vehicle propulsion, and combusting various forms of carbon to produce heat ultimately result in greenhouse gas emissions – specifically emissions of carbon dioxide.

Just as Canadians and the international community have gained an impressive level of understanding of carbon dioxide emissions sources and impacts, we also have an equally impressive lack of knowledge when it comes to the ‘other’ sources of greenhouse gas emissions, and the ‘other’ significant greenhouse gases themselves – methane (NH4), nitrous oxide (NO2) and chlorofluorocarbons (CFCs). Though less significant than CO2 in terms of the amounts emitted annually, these GHGs all have a higher ‘Global Warming Potential’ (GWP) than carbon dioxide. That is, each molecule of these gases has a greater impact on the greenhouse effect than a molecule of CO2.

Perhaps the most bizarre and unexpected source of these greenhouse gases is ‘enteric fermentation’. In another word: cows. Cows managed to produce nearly 3.1% of Canada’s total greenhouse gas emissions in 2007. That was nearly 3 times as much as domestic air travel, and nearly equal to mining and oil and gas extraction.

Agriculture contributed a further 3.9% of our GHGs thanks to the intensive use of NO2 fertilizers on cropland.

Both very old and very new methods are being studied, tested, and deployed in these fields to address the problems.

The methane-belching cows have led to innovations in the study of their diets, genetic selection, and, fascinatingly, a vaccine that may immunize the cows in order to prevent methane-flatulence. Australia, whose cows and sheep are the islands largest methane emitters have been leading the way in this field. However, such vaccines may not be the most organic solution, and organic may be the simplest of solutions.

In terms of the 29,000 kilotonnes of nitrous oxide that our cropland contributes to the atmosphere annually, local, healthy food movements pushing the agricultural clock backwards in time towards the age in which everything was organic, may in turn help farmers reduce their NO2 contribution.

Though, in Canada, our abundance of wood products means that emissions from cement production are less than one percent, globally, “depending on whose figures you believe, cement produces between 5 to 10 per cent of the world’s manmade carbon dioxide,” according to leading British environmental journalist George Monbiot.

Unfortunately, construction of mega-malls and other large projects often consist of concrete, and globally, cement emissions have been growing at nearly 5% a year. This has led some environmentalists to  reconsider their position on forestry – those who were once branded as tree-huggers have now come to embrace the sustainable use of forest products because the forests which are lost are now being renewed. As proponents of wood waste burning technologies will attest, forests are a renewable resource, when managed correctly by such bodies as the Forestry Stewardship Council (FSC).

Another potential environmental windfall is the use of geopolymeric cements, a method that produces 80 to 90 percent less CO2 than conventional cement.

Finally, landfills manage to contribute just under 3% of Canada’s GHGs in the forms of CO2 and methane. Once again, given the right political and economic will and a little technology, there is hope for this sector as well.

Landfill gas industry documents (yes, there is a landfill gas industry!) reveal that 42 sites across Canada manage to capture nearly one quarter of the landfill gas emissions and turn these emissions into heat and electricity. One project alone in Montreal provides energy for more than 8,000 homes.

While the non-result of the talks in Copenhagen gave many environmentalists more than enough reasons to throw arms up in despair and chastising words at world leaders, it seems that in this field, all one needs to do is find the problem in order to be led towards a solution.

// Jens Ourom,
environmental columnist

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© 2011 The Capilano Courier. phone: 604.984.4949 fax: 604.984.1787 email: editor@capilanocourier.com