Earlier posts discussed how primitive life forms (archaea) produce methane in the rumen, and how this is an essential part of a ruminant's digestion. And how it allows cows to extract nutrients, and build complex, high value proteins with bare-bones building blocks of forage. And how that makes cows special. More special than some other meat-producing animals who themselves require complex and expensive proteins in their diet (yep, I'm looking at you Mrs Chicken Licken, and you too Mr Porky Pig).
Well, it's time to look at some of the potential flip side of ruminants and methane. Just how bad is it?
I hope you like the photo as much as I do. It's there to make a little point: we all want to keep that pretty bit of snow on the mountain peak, because I think we understand it's important the World doesn't get too warm, and the weather systems don't change, and the polar ice caps don't disappear. The phenomenon of Global Warming, exacerbated by "greenhouse gases", predominantly carbon dioxide but also methane, is pretty much accepted by the scientific community, and I accept it too. I think most rational and intelligent, scientifically minded and curious, reasonably well-read people get it and believe it's something we need to consider and act upon. I ain't dealing with you here if you're a Donald Trump!
With this in mind, like many people, I've wanted to know more about cows and methane. This isn't chapter and verse, but here's a bit of what I understand about the situation.
Methane is a recognised greenhouse gas. A reasonable proportion of that which is released into the atmosphere every year, probably about 25%, is produced by ruminants, most of them farmed.
The most important greenhouse gases are water vapour, carbon dioxide (CO₂) and methane (CH₄), in that order. Methane accounts for approximately 5-10% of global warming effects, but on a pound for pound basis, it does have a more potent global warming effect than carbon dioxide. This means that if methane can be reduced easily (e.g. extracted from the atmosphere), it could mitigate rises in CO₂ which are happening much faster, largely due to consumption of fossil fuels.
The greatest contribution to total greenhouse gas emissions comes from the extraction, production and consumption of carbon energy resources: that's fossil fuels like oil and gas, but also burning of trees.
The proportion of methane in our atmosphere which comes from cows (and sheep, and alpacas...) is pretty stable as long as the cattle population does not alter. Basically, methane which was once from cows is breaking down roughly as fast as it's being released. However, a rising global ruminant population would see a likely rise in methane. Whilst there's evidence that the atmospheric methane levels are going up, it isn't necessarily due to ruminants.
Fossil fuel consumption produces methane too: about 30% of global methane. This proportion is thought to be rising because we burn more and more fossil fuels.
Most methane production, around 50%, is from natural sources, such as soils, oceans etc. Actually, wetlands (there's a huge amount, and even more as the permafrost regions of Siberia etc. thaw out) are thought to be the biggest contributor to atmospheric methane.
Methane breaks down naturally after around 10 years (CO₂ on the other hand takes around 120 years). As long as production is not increasing, it can be considered a natural cycle.
Wetlands are a fascinating example: wetlands are a CO₂ sink as well as a CH₄ producer. As the permafrost thaws, in the short term, the increase in CH₄ might give a net global warming effect, but over a 400 year cycle (and because CH₄ has that shorter life-span, remember), wetlands have a net global cooling effect, as they sink more CO₂ than they produce CH₄.
Basically any plant life is good, as it uses CO₂. Permanant vegetation is by far the best. Think rainforests and permanent pastures, not fields ploughed annually for cropping.
If we don’t want methane from ruminants to increase yet are happy to allow them to maintain a status quo (cycle), we do need to keep the global ruminant population about the same. More cows and sheep would be a problem (but there's gonna be more people to feed...so it is very reasonable to suggest we all eat a bit less meat and dairy, if we're having more than our share).
There are arguments that forage-based ruminant farming, done the right way, can have benefits by locking up carbon - so-called regenerative agriculture. This is not the case for cereal-fed animals (pigs, poultry etc.).
The more forage a ruminant eats (the diet they are designed for) the more methane they produce. It is a really important and healthy part of her digestion and it gives her an ability to extract nutrients from plant materials, especially pasture, that other animals simply can’t access.
In my work, I come across a lot of stuff aimed at reducing methane output from individual cows and these usually involve feeding things which are essentially toxic to the normal rumen microbiome, or by feeding less forage, and more cereals. Please look out for these spurious cures - they are commercial bullshit.
If we apply tactics which reduce methane production per se by individual animals but without due consideration of the wider consequences, we’ll end up in trouble.
Cows are often used as an easy excuse for global warming. Unfortunately, I suspect much of these messages are purposeful diversionary tactics used by lobbyists and commercial operators whose agenda is to attract people’s attention away from things they don’t want us to acknowledge. Or by people who simply want us to stop eating meat, or farming animals, for other reasons (like their deeply held beliefs that it is wrong). Or by companies who want to sell us meat or dairy alternatives. There's a LOT of that. Yep, oh-so-cuddly Oatly and never-harm-a-fly Amy's Kitchen-like brands, I'm now looking at you!
Since 1990, net greenhouse gas absorption by forests globally has reduced from around 75 million tonnes to around 40 million tonnes of carbon equivalent.
We need more forests. And we desperately need to preserve those we already have.
By all means give up dairy foods and eating beef and it is everyone's prerogative to do so. But please don't believe you are doing it to save the planet. Unless you are giving up all food (unlikely!), the alternatives are likely to be at least, and probably more, damaging environmentally. Soya, sadly, is one of the worst. Apparently avocados (I love an avocado, me), are apparently not much better.
We should probably consume less of everything. We definitely shouldn't waste food!
The beef and dairy industries do have a responsibility: there's a lot which can be done to improve sustainability (e.g. more from forage; regenerative practices; improve soils). There's a lot which can be done to improve efficiencies too, such as less waste; better cow health; better dairy cow longevity. It's something many farm vets are very focused on right now.
Preachy is not a good look. Sorry if I've come across a bit that way in this post. I'm no expert in global warming, I just understand cows and what they can do, and recognise their unique place in the whole global ecosystem, especially when farmed as part of regenerative methods (forage based). Really, I simply wanted to get some of the facts about ruminant methane out there today because my aim is to make it easier for people to make their own informed decisions.
Next post will be a more light-hearted one, I promise!
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