Sheep: The sacrificial lamb for emissions.

Conversations | 7th July 2023 | By Andrew Whitelaw

The Snapshot

  • Agricultural emissions are going to continue being a focus for governments.
  • Australian ag emissions have dropped 20% since 1990.
  • The majority of ag emissions in Australia are methane from livestock.
  • The largest driver of our reduced agricultural emissions has been the decline of the Australian sheep flock.
  • After twelve years, the emissions from livestock are no longer in the atmosphere.
  • The low-hanging fruit of the 20% fall in GHG emissions in Aussie ag has been easy, it’s just required a smaller flock.
  • The next question is how governments will push for reduced emissions without reducing productivity.
  • Our emissions from sheep are the lowest since the early 1900s

The Detail

In agriculture, there is a huge amount of debate regarding climate change. Some believe it is occurring and man-made, and some don’t. The debate is largely irrelevant now; governments and the wider society are making their mandates through voluntary programs or government interventions.

I am not a climate scientist, but I thought it would be interesting to delve a little further into the data after attending a presentation on Australian environmental sustainability by ABARES. In this presentation, they displayed some charts on Australian sustainability. One that caught my attention was the one below, which I have replicated as part of this analysis.

The data on emissions used in this short piece is sourced from the United Nations Framework Convention on Climate Change. In this short article, we will take these at face value, however, these may not be 100%, as they are quite generic values more collection of accurate data that reflects reality is required.

The chart displays a range of nations (and blocs) worldwide and their change in greenhouse gas emissions since the baseline of 1990.

The main point is that Australia has done pretty well. Our emissions are well down from the starting point. What has driven that? Has it been our innovation? Let’s take a look.

Let’s look at the annual emissions in the chart below. The term CO2 is commonly used when referring to emissions. In reality, greenhouse gasses are a mixture of various compounds, and CO2 equivalent is what should be considered.

The chart below shows the annual emissions since 1990; we can see that overall agriculture emissions have declined.

The majority of agricultural emissions are in the form of methane (more in a future article). These are emissions produced through enteric fermentation, the majority through our sheep and cattle flock, but it is sheep that I want to focus on.

We have written about the relationship between sheep numbers in Australia and cropping acres (see here). There are many reasons sheep numbers have declined; economics and lifestyle choices are just two reasons.

The chart below shows the sheep flock vs Australian greenhouse gas emissions from 1990 to the present. 1990 is the baseline for when emissions data is available, so many use this as a point to make comparisons for ag emissions, i.e. Australian ag has 20% lower emissions than 1990.

Something else occurred around that time, in 1991, the collapse of the reserve price scheme, which started the decline of the Australian sheep flock.

What we can see in the chart is that there is a close relationship between the declining sheep flock and the reduction in overall emissions.

The chart below shows the correlation between the sheep flock and GHG emissions. It is a strong correlation. As the sheep flock declines, so does overall agricultural emissions.

The UNFCCC provides data on the volume of emissions created through sheep enteric fermentation. If we compare these emissions against the total sheep flock, we can see that they are declining, with a  correlation of 0.99

If we delve further, in the second chart, the emissions per sheep is calculated. We can see that the emissions per sheep are at similar levels to the baseline in 1990. This is clearly a rudimentary value, based on the UNFCCC data versus the sheep flock numbers.

I have modelled (rudimentarily) the emissions the industry would have produced from 1900 to the present. In theory, our emissions are lower than most of the past 120 years.

To me, the accusations of agriculture being a major emitter are most likely hyperbole. Our emissions versus productivity will be substantially lower than they were in the past. In the same period since 1900, we have gone from the horse as a means of transport to cars, planes and rockets.

I feel they would have a bigger influence than our agricultural industries. As an industry we have to be careful about what policies we follow, or that the government introduces to further reduce our emissions. We don’t want to get to lower emissions just through removing industries.

What does this all mean?

We all have our views on climate change and emissions. I feel that agricultural emissions should be treated differently from other products. A tonne of emissions used to produce an essential product, such as food, should not be considered the same as a tonne of emissions used to produce a gimmicky plastic toy which will be thrown away after a few months.

If the data is correct, then Australian agricultural emissions are down on the 1990 baseline, which is, in theory, great. However, it is largely attributable to the decline of the sheep flock.

We could call this 20% the low-hanging fruit, as the decline of the sheep industry has reduced the overall emissions.

This was an unintended ‘benefit’ of the sheep flock decline, but if the industry is required to reduce its emissions further, we don’t want to do it through the decline of the industry.

We want to do it through producing more per ha/beast, whilst maintaining or reducing emissions. The problem is that much of the science required to achieve these gains is hampered by stakeholders against their use i.e. glyphosate.

Additional note

It is important to note that emissions from sheep are methane, which stays in the atmosphere for a shorter period than carbon dioxide.

Methane stays in the atmosphere for around 12 years and has a decay of 8.3% per year. This means that emissions from 2011 no longer contribute to greenhouse gas emissions.