We have covered some serious subjects over the past few weeks, so I thought this time I would talk about something a little bit more light-hearted, at least on the face of it.
Back in January of this year, there were reports from Germany of an explosion – a herd of cows nearly took the roof off their barn because of the amount of methane they were releasing, when a static electric charge caused it to explode. The blast damaged the roof of the barn and one cow (out of about 90) received minor burns.
This incendiary subject has a serious side, of course. The world’s 1.5 billion cows and billions of other grazing animals emit dozens of polluting gases, including lots of methane, as a result of their digestive processes. Methane is a greenhouse gas, 23 times more powerful than carbon dioxide, and with the potential to contribute massively to the greenhouse effect, trapping radiation from the sun and resulting in global warm.
Agriculture is responsible for an estimated 14 percent of the world’s greenhouse gases. Domestic cows emit an immense amount of methane through belching, and annually they expel a vast amount, about 60 percent of global methane emissions, or equivalent to the carbon dioxide emissions of a car burning 21,400 litres of petrol!
As world economies develop and many countries’ dietary intake of meat increases, the number of animals being raised for food, and so the quantity gas they produce, is a growing concern that needs to be addressed. It has become the subject of study by academic researchers. But how best to study cow burps?
One method proving popular with researchers in England, Scotland and South Africa is use of remote sensing using technology based on infrared laser absorption spectroscopy. Methane absorbs infrared light. A laser beam is directed to wherever a “gas leak” is suspected, and the detector measures the average methane gas density between the detector and target.
This technology is proven and widely used in the environmental engineering industry to detect methane gas leaks from pipe-lines and landfill sites.Researchers can position such a monitor a few metres away from a cow’s mouth to record the burp and level of methane exhaled.
An article featured on the BBC website, back in 2010, focused on farmers using such a technique to monitor cows’ emissions. More recently, there was also a BBC documentary called “Should I eat meat?”, which focused on showing levels of methane released by cattle.
It will be with gas detection studies such these that the world can hope to resolve the conflicting imperatives of providing meat for the world without causing it to overheat.