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I read about the Biogenic Carbon Cycle on the UC Davis website:

"As a by-product of consuming cellulose, cattle belch out methane, there-by returning that carbon sequestered by plants back into the atmosphere. After about ten years, that methane is broken down and converted back to CO2. Once converted to CO2, plants can again perform photosynthesis and fix that carbon back into cellulose. From here, cattle can eat the plants and the cycle begins once again. In essence, the methane belched from cattle is not adding new carbon to the atmosphere. Rather it is part of the natural cycling of carbon through the biogenic carbon cycle."

According to that logic, burning fossil fuels also is not harmful for the environment, because the CO2 eventually gets consumed by plants.

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pjc50 7 hours ago | parent | next [-]

This also ignores the different GHG effects of methane vs CO2.

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shkkmo 39 minutes ago | parent | prev | next [-]

> According to that logic, burning fossil fuels also is not harmful for the environment, because the CO2 eventually gets consumed by plants.

No, the difference in logic is based on the source of the CO2. Fossile fuels are burried in the ground and are not part of the carbon cycle. By removing them from the ground, we are adding new carbon to the carbon cycle rather. Coversely, if you burn wood, that carbon was (mostly) going to end back up in the carbon cycle and you've just sped up it's cycle and increased the portion of the cycling carbon that is in the atmosphere.

There are changes we can make to the cycle that do affect global warming (cutting down all the forests and killing all the kelp would greatly decrease the capacity of the cycle). Conversely, we can expand the carbon cycle by planting trees (that actually survive and form forests.)

However, you can't fix global warming by expanding the carbon cycle because you can't scale the natural cycle to match all the new carbon that is being added to it by buring fossile fuels. There are only two solutions, adding less carbon to the cycle by burning fewer fossile fuels and finding ways to remove carbon from the cycle by sequeresting it in long term ways.

Carbon taxes can fail to actually cause change if they allow fossil fuel burning to be offset by temporary bumps to the carbons cycle capacity because this doesn't really solve the problem and at best slightly delay it.

Cow "farts" (actually burps) are kinda the opposite, the methane is already part of the carbon cycle. However methane is a way more potent greenhouse gas than CO2 so by increasing amount of carbon cycle that is amospheric methane you are accelerating global warming until the methane decays into CO2.

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blitzar 7 hours ago | parent | prev [-]

Unfortunately powerplants dont graze on a field of grass

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shafyy 7 hours ago | parent [-]

A few of things:

1) Even if cows would only eat the grass that was there (and we would not have converted any forest or other vegetation into grazing lands), the methane and CO2 stays in the atmosphere for a long time before being used by plants again, contributing to the greenhouse effect in that time. The reality is, we can only cover a very small percentage of the demand with this "3 happy cows on a vast pasture" phantasy. Most cow feed is planted additionally, often in countries like Brazil, and then fed to the cows.

2) The carbon impact is not the only negative impact of the scale of livestock agriculture we run these days. As it says in the article, another big impact is eutrophication of water bodies.

3) Just basic physics: Livestock agriculture, especially beef, is a very inefficient way of producing protein and calories. Have a look at this data: https://ourworldindata.org/grapher/ghg-per-protein-poore

So, please don't come at me with your cute comments. The reality is that we have too much livestock agriculture. It's not sustainable to feed 8 billion people like this. The scientific consesus is clear on this.

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valval 6 hours ago | parent [-]

The data you present again doesn't take the lifecycle into account. Also worth pointing out that protein bioavailability and amino acid profiles are ignored.

Unrelated but since you brought the topic up, it would of course make sense that releasing vast amounts of CO2 into the atmosphere that took millions of years to bind into the earth in mere decades might be a bad idea. Then again, we're only guessing there as well. We have no clue if the world will be better or worse for us to live in 50 years, and how much of it will be attributable to CO2.

But I digress -- this comment thread was about cow farts and the utter silliness of grasping at such straws when speaking about an otherwise serious subject like the futures of our children.

	▲	shafyy 6 hours ago \| parent [-]
		> Then again, we're only guessing there as well. Umm, no, we are not guessing. But I see where this will end, so let's stop this discussion right here.