Researchers are working to find ways to make cattle, sheep and pigs produce less gas.
After a long hard look at the options, Associate Professort Richard Eckard from the University of Melbourne has concluded that we're still some decades away from finding the solution.
Dr Eckard advises the Food and Agriculture Organisation on climate change research in agriculture.
Presenter: Geraldine Coutts
Speaker: Associate Professor Richard Eckard, climate change research in agriculture, Food and Agriculture Organisation
ECKARD: The methane gas itself is quite powerful as a greenhouse gas, so it's about 25 times the global warming potential of carbon dioxide on a 100 year basis, but if you take it on a 20 year basis, it's actually about 72 times more powerful.
COUTTS: What can be done about it? I said in the introduction that lots of efforts have been made to maybe change the eating habits of the cattle so they produce less of this methane gas, but close are you in getting to produce less?
ECKHARD: Look, there's quite a few things we've done recently that can make a difference, just improving the quality of the cattle's diet and adding dietary oils into their diet has reduce methane by about 20 percent. So they've found some things that we can do now but they're not really the long term solution to reducing methane. The long term solution lies in more sustained research effort, to try and change the microbial function of the animal.
COUTTS: Well, how can you do that?
ECKHARD: Oh, there are a number of ways. There's a group in New Zealand working on a vaccine to reduce methane. The ....? just incredibly complex, the stomach of the animal and there's just so many different microbes with different functions in there and we're only really just coming round to understanding what they actually do and how we can control them sustainable and that's the real challenge why we mentioned it. It's a long term venture.
The policy in .......? is a fairly recent emergence in the last ten years, the policy imperative to reduce methane. But the research has only just started as well and a lot of this research takes up to 20 years before the sustainable solutions come through.
COUTTS: And so are genetics an issue and are you looking at that and can they be manipulated to overcome the problem?
ECKHARD: Well certainly, there's almost, there's two ways we can actually breed animals. We can breed animals that produce less methane itself. We're not sure that's the answer, because it's not really an imperative for farmers to breed, for animals to produce less methane on its own and we're not sure what connection that has to production or productivity of the animal. But you can also continue to breed animals that are more efficient and they just partitioning into production than they are into waste products like methane. So there's optimism there as well. Again, that's about a 15 year to get to the point where we actually make substantial gains.
But breeding certainly is a long term sustainable direction as well, because you're actually progressively improving the situation.
COUTTS: Well, and are there many different kinds of methane, some more dangerous and lethal to the atmosphere than others?
ECKHARD: Eh, no, there is an argument that methane from animals is a part of the actual carbon that's involved. It has come out of the atmosphere into plants, through the animal and is released as methane. So it's slightly different to say fossil methane, which comes out of long term stored carbon that never was in the atmosphere. So there is an argument that there's about a one times difference between say mines the methane or methane that comes out of coal seamings, or the methane that comes out of animals.
But once it's in the atmosphere, the atmosphere is just sees it as methane and it's just powerful, it doesn't matter where it comes from.
COUTTS: Well, I was just going to ask you that. I mean how do you differentiate between carbon to know or the methane to know what it's source is?
ECKHARD: Well, we can't actually. Once it's in the atmosphere, the atmosphere sees it as methane, so just about as bad,
COUTTS: So we might be unnecessarily blaming the poor old cow?
ECKHARD: And that's an issue. If you've got large sources coming into the atmosphere from say melting of perma-frost, and you've got large sources coming in from opening up new coal seams, for example. Then the cattle themselves, that's all mixing in the atmosphere and the atmosphere just sees it as methane.
COUTTS: Well, there are other issues, of course, that we're seeing now and the UN report on methane emissions from thawing perma-frost has sparked global concern. But methane emissions from agriculture drawf the output of perma-frost, so perma-frost more of an issue?
ECKHARD: Well, it depends on how it's released. The potential amount sitting in that perma-frost is really big and if it all thaws in a few years, well, that will dwarf what's coming from livestock methane. If you said, well, take the total amount of perma-frost that could be released by say 2050 theoretically and you compared it on an annual basis to what's coming from livestock methane, then perma-frost will not be smaller. But the problem is we don't know how much is being released from perma-frost and what's sort of rate it might be or what sort of rate it might accelerate to over time. So it's quite hard to compare it livestock methane. So we're pretty sure what the estimates are from livestock methane, because we know roughly the cattle numbers around the world and they're fairly consistent in how much they release, depending on the kind of diets they get.
COUTTS: Well, what's in the pipeline for you now, what are you up to at the moment in this research?
ECKHARD: I think we're working particularly our group, are working on dietary supplements, so what can we add to the diet of animals, for example, looking at waste products that come out of other processing sectors. So we worked on dietary oil seeds, coming out of whole cotton seeds, coming out of bio-ethanol or bio-diesel production and recently tried a grape mark which is a by-product after you squeeze the juice out grapes for wine production and that grape mark has had quite a big impact on reducing methane as well.
So looking at it, we can actually have products that come out of other processes that are generally waste products and the animals can benefit from them.
COUTTS: Alright, so we hear a lot about temperature rise and climate change and all the rest of it. How much time have we got to reduce the methane and other gases before it's critical?
ECKHARD: Well, I think most of the indications are it's critical right now and so that's why there's ani imperative for us to do this work that we can actually see reductions, real reductions now that we can achieve right now, that also have a pathway to a longer term future where we can continue with livestock production sustainably, but that have these longer term options come through. So I guess the talk that I was giving at the conference last week was really focused on let's do what we can do now and there are some things about feeding and breeding we can do now, but let's also sustain the efforts to get to that longer term objective which is about changing the way the microbes operate in the animal and to have that larger reduction for a longer term future.