The math here is quite simple.

A single cow can produce around 250 to 500 liters of methane per day through belching and farting. Let's take an average of 400 liters/day. Methane is a potent greenhouse gas.

400 liters/day × 365 days = 146,000 liters/year.

Convert to kilograms (since methane’s density is ~0.656 kg/m³):

146,000 liters = 146 m³ → 146 × 0.656 kg = 95.8 kg of methane/year per cow.

Methane has a global warming potential (GWP) of about 28 times that of CO₂ over 100 years. So, 1 kg of methane is equivalent to 28 kg of CO₂ in terms of warming effect.

95.8 kg of methane × 28 = 2,682 kg of CO₂ equivalent per year per cow.

2,682 kg CO₂e/year × 1 billion cows = 2.68 billion metric tons of CO₂ equivalent annually.

Cool. Now compare cow farts to all other sources, that’s the only metric that matters.

A quick search shows that global c02 emissions are about 35 billion tons.

So the cow farts are a bit less than 8%. That isn't insignificant.

And how much of a dent would reducing cow consumption by 25% make?

You said that cow emissions weren't significant (well, that it was "absolute lunacy").

Two people have provided rough calculations that show they do have a measurable effect.

What's your point?

My point is people should do the math and come to their own reasonable conclusion. Assuming these numbers aren't totally bullshit (see what I did there) this won't move the needle unless we cut out cow consumption 100% and cull all native herd animals.

Me? I think we can probably survive some cow farts as our ancestors who hunted buffalo and burnt down entire ecosystems doing so did. We should focus on the real solutions that will move the needle, like proper human-scale city design and nuclear power.

Knowing they alone account for over 1/20th of the climate change effect though is useful information.

Maybe there are other ways we could reduce their methane emissions short of getting rid of all of them.

I agree that other solutions are needed to properly address climate change though.

There’s a ton we can do before taking food off our children’s table.

I don't think anyone was talking about taking food off children's tables?

Because that's exactly what reducing farming output does.

I don't know enough about this topic but my question is what is the input to the 250-500l cow fart equation. What's being consumed to produce that much methane?

A 2% reduction is absolutely moving the needle.

There is no silver bullet that's going to be a 25% reduction all on its own. The only way to win is a combination of changes each of which reduce emissions by a few percentage points.

Hmm, lets see: 8% * 25% = 2%

You can actually reduce how much methane cows produced by changing their feed by like 80% or something

Farting maybe, but the impact from cow burps is measurable and no conspiracy theory.

https://pubmed.ncbi.nlm.nih.gov/17517715/

The parent did not say anything about climate and pointed to actual the problem in The Netherlands: nitrogen deposition. Our nature parks are dying because there is far too much nitrogen deposition from nearby farms.

(But our current right-wing populist government likes to pretend the problem does not exist, so they have to be slapped on the wrists by courts and the EU.)

Now that’s a real problem, farm animal excrement is an issue. Seems like one that technology can solve?

That's what the industry has been saying here for decades and they tried a lot of things, but the problem has only gotten worse. At some point you have to say - apparently you can't fix it, so we have to buy out farmers near nature reserves.

But the farmers have been intimidating politicians by blocking highways and inner cities with tractors and other equipment. Funnily, if anyone else does this they get arrested, but farmers get a carte blanche to disrupt society.

How do we keep people fed after shutting down farming (at a reasonable cost)? The entire thing seems anti-human…

Nobody wants to shut down all the farming, just reduce it. For example, the Netherlands produces 250% of its own meat consumption. Since it's subsidized, the net financial gain is very low. You could say reducing the production to 125/150% of consumption would leave enough for local consumption plus a little export in good times or a buffer in bad times.

Unfortunately, big agricultural companies hired a marketing company to start a political party which claims to be pro local/small farmers, but is actually just pro big agriculture.

Eating less meat?

The questions are mainly targeted at the consumption of animal products: meat, dairy products and eggs. Their research shows that reducing the consumption of animal products, and therefore switching from a meat-eating to a vegetarian or vegan diet, reduces land requirements by two-thirds.

https://www.uu.nl/en/news/calculate-the-land-use-impact-of-y...

Not everyone even has to stop eating meat. Just reducing meat consumption to 1-2 days per week would go a long way.

So in other words you want to reduce everyones quality of life. Let me guess, when people object and then go vote the parties you don't like you are going to blame everyone except these kind of policies.

Make no mistake, these hypocritical do-gooder authoritarians will still be flying first class and eating steak while they force us proletariats to eat bugs and soy sloop.

The project aims at shit to no only a portions of the farms, and especially one from the meat industry. They’ll still have plenty of food.

Farm animal excrement is far from the whole picture. Fertilization is the main contributor (and animal excrement is used for that, but far from exclusively).

Yeah, fertilizer getting into the watershed is a real problem. It wreaks entire ecosystems.

I would gently encourage you to engage with the topic rather than a puerile dismissal as “farting cows”. Agriculture is one of the main drivers of climate change (~30%), and and also has associated land usage implications. Ruminants (“farting cows”) directly produce around 6% of our total emissions.

I was just reusing the term op used. And that’s a tiny percentage if the trade off is keeping humans fed.

No, it's a huge amount relative to the nutrition it actually provides. There is so much terrible (by any metric apart from maybe direct monetary cost) meat consumed and there are vested interests in a lot of industries to maintain that status quo.

Don't get me wrong, good meat is delicious and there are plenty of ecosystems that require grazing and large herbivores to maintain, but the current system is devastating and doesn't provide nearly as much nutrition to the end user as it consumes in its production.

It's not - in New Zealand 35% of GHG emissions are from cattle, with over 53% from agriculture in general.

Source: https://environment.govt.nz/publications/new-zealands-greenh...

This is a strange companion, NZ has like 6 people and their main focus is agriculture. Anyways, I bet their volcanos put out an order of magnitude more.

Do the math. Then comment.

I did the math, others seemed not to. Cow farts are insignificant, period.

> Cow farts are insignificant, period.

If that was your conclusion, then you did the math wrong, or did not understand the math.

I understand the math, cows aren't the problem.