As the heat of methane increases, is it time to rethink measurement?

AS the environmental impact of livestock-related methane emissions becomes a hot topic in the global climate change debate, calls are growing for wider recognition of more meaningful ways to represent the industry’s footprint.

Livestock has been at the center of climate policy in recent weeks, as the federal government seeks to sign the Global Methane Pledge and other countries, including New Zealand, impose restrictive legislation on livestock farmers.

As many countries look to livestock emissions and the industry puts in place its own measures, such as the goal of being carbon neutral by 2030, there are still concerns about how livestock emissions are accounted for. within the scientific community.

The current measure used to represent emissions in most industries is called GWP 100 (Global Warming Potential), which aims to place all gases on a common scale of “CO2 equivalence” over a time horizon of 100 years.

But CSIRO Principal Investigator, Agriculture and Food, Dr. Brad Ridoutt said the GWP 100 is not the only way to aggregate emissions and may not necessarily be the most relevant way for the livestock industry to report emissions and direct action climatic.

“Methane emissions have a relatively short-term impact on the climate, unlike CO2 and other longer-lived greenhouse gases (GHGs),” he said.

Dr Ridoutt said the main scientific body, the Intergovernmental Panel on Climate Change (IPCC), had distinguished between different gases.

He pointed to this quote “Stabilizing the climate will require deep, rapid and sustained reductions in greenhouse gas emissions and achieving net zero CO2 emissions. Limiting other greenhouse gases and air pollutants, especially methane, could have both health and climate benefits.

Dr. Brad Ridoutt

Several other measures have been developed to better represent livestock emissions – the best known is a method from the University of Oxford called GWP star. Dr. Ridoutt was also involved in the development of a methodology called the radiative forcing (RF) fingerprint.

“With GWP star, it looks at whether methane emissions are increasing or decreasing over time. However, livestock emissions can go up and down like a yoyo, with seasonal conditions and expanding and contracting herds. This creates problems with the GWP star as it can be difficult to discern a consistent rate of change,” he said.

“The radiative forcing fingerprint has some similarities to the GWP star but is simpler.

“GHG emissions contribute to global warming by increasing radiative forcing. The RF footprint aggregates the RF from current emissions with the residual RF from historical emissions. This way we see if the industry is increasing its overall footprint or decreasing it. When the RF is stabilized, the industry can be considered “climate neutral”, i.e. it no longer adds to climate change. That’s what the Paris Agreement is for, stabilizing the climate.

“That’s what I showed with the sheepmeat industry, that industry is no longer adding to further climate change.”

How livestock industry emissions are reported

All sectors, including livestock, have their emissions reported annually in a federal government document called the National Greenhouse Gas Inventory. MLA publishes its own GHG footprint, which includes information similar to that of the NGGI.

Dr. Ridoutt suggests the red meat industry use a metric like RF fingerprinting.

“They should use whatever metric is relevant to them and take a proactive approach, as it gives better insights with respect to the climate stabilization goal. Industry can voluntarily report whatever they want, as long as it is scientifically based and factual.

In response, the MLA CN30 manager Dr Margaret Jewell said investment is currently underway, via Dr. Ridoutt, to enable the use of these measures, with results expected towards the end of this year.

“In Australia, we aim to use whatever metrics we can, because we think it’s important to report in a really transparent way on the impact of livestock on the climate. It’s also important so that we can define appropriate policy and mitigation measures,” said Dr Jewell.

Moving away from GWP 100

Dr. Ridoutt said the universal use of GWP 100 was not warranted. The results can be difficult to interpret when there are large short-term emissions such as methane.

“We have to look at what we are trying to achieve and under the Paris Agreement it is to keep the global average temperature below a 2 degree rise – ambitiously 1.5 degrees,” said he declared.

“Throughout the IPCC reports, they don’t prescribe any measure and they caution against using a particular measure because it might not answer the question being asked.”

Dr Ridoutt said methane reduction was important because it can allow the industry to grow without increasing its RF footprint.

Alongside Dr. Ridoutt, several respected scientists, including Professor Davis of the University of California Frank Mitloehner and professor at the University of Oxford Myles Allenhave been calling for more transparent measurement of livestock emissions for years.

Professor Allen told a recent survey, led by the Irish government, that he could be the world leader in including measures, like the GWP star, in his greenhouse gas account, alongside the GWP100 measurement.

“We can solve the problem of not reporting the impact of warming tomorrow and you can calculate it at the individual farm level,” he said.

“If you did this it would be interesting for Irish farmers as they would find out what they can do to reduce global temperatures. This reporting problem is not a problem we need to have.

The industry is aiming for carbon neutrality

As the red meat industry continues with plans to become carbon neutral by 2030, MLA Managing Director Jason Strong said the development of metrics such as RF and GWP star are important for the industry. .

“Climate neutrality is one of those little bonuses on the road to carbon neutrality – it’s really important because a lot of global commitments, like the Paris agreement, are based on warming,” Strong said. .

“Methodologies like RF and GWP star are very important, there are a lot of people focusing on them and we will definitely stay through them. ensuring that we have the tools and the suite of solutions to enable people to do so.

“We want to be in a position where we can maintain a bigger herd and a sustainable herd.”

The government does not adopt other methodologies

Beef Central has contacted the Minister for Energy and Climate Change Chris Bowen and asked if the government was considering putting additional livestock emissions information into the NGGI – using parameters such as RF and GWP star. A spokesman for the minister said that was not planned.

“Australia is required to use the GWP-100 metric for reporting under the Paris Agreement. The GWP star method is not currently recognized under international inventory reporting rules,” said he declared.

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