Agriculture accounts for 33% of Irish emissions and rising, but simply reducing the national herd is not the solution, and a new way of measuring emissions could have a profound impact on how the world views Ireland and our agriculture sector, argues Shane McDonagh, environmental researcher at UCC. [Contact details below].
There is a growing recognition that it’s apples and oranges to compare cow burps to cars – and this development will be keenly watched by the agriculture industry.
At a national and global level we measure our climate impact, producing “accounts” of our emissions. When auditing we try to convert everything to a standard unit for comparison and, as the most common greenhouse gas, we tend to use carbon dioxide.
In 2018 a whopping 22% of our total equivalent carbon dioxide emissions were attributed to enteric fermentation and manure management; ruminates such as cattle and sheep producing the powerful greenhouse gas methane from their waste and as they belch.
For the purpose of our national audit, 1kg of methane emissions is seen as equal to 25kg of carbon dioxide (other countries use 28kg) – hence the large contribution of farming to the total. This is based on sound science but doesn’t allow for much nuance – methane emissions from a natural gas leak are treated the same as those from a cow.
However, it now seems that the formula we have used is not entirely fit for purpose. Science is a process of continually challenging and updating our collective knowledge. There are no “alternative facts”, just genuine scientific discussion. And the evidence suggests the effect of agricultural methane emissions on climate change have not been appropriately audited.