Article by Maureen Odendaal, BSc (Hons), MPhil
In recent years climate change has become much more real, with increased climate events such as wildfires and storms, and creeping increments in global average temperatures. The IPCC estimates that agriculture globally shoulders in total about 23% of the blame for Greenhouse gas emissions (GHG).1
Although most of the CO2 produced from farming practices comes from fuels, a significant portion of these emissions derive from tillage practices. When soil is tilled, it is also aerated, and increases the conversion rate of soil organic matter into carbon dioxide. Methane, generated by ruminants, is a much more potent GHG. This means that, in the run up to COP26, the government is under pressure to work towards reducing livestock farming in the U.K, so we need to ask the question: ‘is it actually necessary to reduce U.K. livestock production in order to reduce emissions?
Let’s unpack the arguments. Firstly, we need to ask exactly where the UK sits on the global arena with respect to these emissions. Whilst the average global percentage of emissions due to agriculture, according to the IPCC, sits at about 23%, further analysis of data reveals that only 10% of UK emissions come from the agricultural sector. World-wide regions such as Latin America and South-east Asia contribute far more emissions per capita of GHG compared to the UK. It is also true that the UK emissions have been steadily reducing, whilst this is not true in developing regions of the world. This needs to be factored in when deciding exactly what action should be taken in the U.K. to reduce GHG emissions.
Secondly, it is not generally known that GHG produced by the animals may be considered to be net zero in terms of contributions to increasing emissions because these gases do not cause an increase in atmospheric carbon. The reason why climate change is a serious matter is because of the massive conversion of fossilised carbon into carbon in the atmosphere (for example from the combustion of fuels, melting arctic tundra and landfill emissions), producing gases which trap heat in the atmosphere. However, GHG derived directly from animals is not carbon newly introduced into the atmosphere. This methane forms part of the natural carbon cycle. This diagram shows how:
- cows eat grass
- the carbon in the grass is converted into carbon dioxide and methane
- which is then removed from the atmosphere via photosynthesis and other processes
- And then returned to the grass.2
Methane as part of the carbon cycle is called biogenic methane, which takes only 10 years to be returned reincorporated into living organisms. New Zealand, which depends on livestock farming, already factors in biogenic methane when deciding upon how to reduce emissions.3 Other agricultural countries are considering doing this same. This is not to say that methane from farming is not a greenhouse gas (it is, of course), but rather perhaps we should be doing our calculations differently.
Bearing these facts in mind, U.K. farmers should be asking how they can best protect their industry. There are several simple remedies, such as including methane-reducing supplements in livestock diet. Recent research shows that methane emissions can be reduced by as much as 80%.4 Farmers can also reduce loss of carbon by cultural methods, such as use of cover crops and minimum till: these reduce conversion of soil organic matter into atmospheric carbon. Pioneering farmers in the U.K. are demonstrating how careful farming practice can improve the soil and reduce emissions.5
To answer the original question: ‘is it actually necessary to reduce U.K. livestock production in order to reduce emissions?’: it does not seem to be an urgent problem for climate change. If biogenic methane is factored in, and trends in farming towards regenerative practices continue, we can expect to see a decline in levels of GHG from agricultural practice without disrupting our industry or making major changes.
