I never claimed the phenomena was unique to this situation - it's a general phenomena.
Deforestation is a real problem. How do you address this from a policy perspective? If you ban beef, that is only a temporary band-aid on the real problem of deforestation, which both fails to address deforestation properly, and which prevents beneficial uses of livestock such as for reuse of food waste products, grazing of natural grasslands, production of natural fertilizer, etc.
It's a concern, but fortunately if cattle population stays constant, their portion of the atmospheric resident methane will also remain constant, because methane degradation will keep pace with emissions.
Compare this to cars. Even if the number of cars remains constant, their contribution to the C02 pool grows every day.
So we should avoid increasing cattle population 100x, but we wouldn't want to do that anyway because we'd have nowhere to put them, and I certainly wouldn't support deforestation.
You make a strong argument. I think this is a case where we'll find the global optimum somewhere in the middle.
Deforesting the amazon to grow corn for cows is something I'm sure we can all agree is bad.
Should we use livestock to eat cover crops and waste products like corn husks and cobs? This way we reuse waste and produce high quality protein to supplement our diets.
Should we graze cattle on natural grasslands like the great plains? Especially in rotation with human foods, like the cover crops mentioned before?
There is a certain amount of carbon in the atmosphere, and a certain amount of carbon in the ground.
When you burn oil, you take carbon from the ground and introduce it into the atmosphere. This increases the total amount of carbon resident in the atmosphere.
When you grow plants, you take carbon out of the atmosphere. When you eat it, you release it back into the atmosphere. The total amount of carbon resident in the atmosphere does not change.
Grass grows more vigorously when regularly pruned, for example by a grazing animal. Farms also make a point of planting thing which grow quickly and efficiently. Thus it's reasonable to expect that farming could increase the rate of carbon turnover in the atmosphere, which would create the appearance of increased carbon emissions without a corresponding increase in the amount of carbon resident in the atmosphere.
In practice, farms regularly use synthetic fertilizers. They might cut down trees to clear fields for animals. They use heavy, oil burning equipment. These, and many other practices, actually increase atmospheric carbon, and for that reason should be discouraged. But the cow itself only causes a short lived, fixed increase in atmospheric methane and an increased rate of carbon turnover.
I suppose some people may consider stable to be overstating this situation. Nevertheless, when put into context of natural wild herd sizes as done by krrrh https://news.ycombinator.com/item?id=26543346 , I believe my overall point stands.
I agree we should not ignore detrimental environmental effects. However we should strive for a nuanced view which attempts to determine root causes.
The root cause of artificial fertilizers is fossil fuels.
The root cause of feedlot runoff is... feedlots? I'm not sure if there's something more fundamental at play here. I'd like to see a fundamental analysis of this.
Cattle feed is generally not human edible, that's the beauty of ruminant animals. Even conventionally raised cattle usually grow up on grass, only to be finished on grain. Granted as cattle are slaughtered at younger and younger ages, the grain finishing portion is consuming a larger percentage of their overall lifetime feed stuff. But even so the grain they're eating wasn't going to just end up on your dinner plate. They eat the husk and all. And besides this is only bad insofar as growing food in general is bad, so that's the root cause.
You missed deforestation, which we discussed elsewhere in the comments. I recommend to check it out.
Yes that's right, plants can't tell the difference between a carbon atom which came from fossil fuels, and a carbon atom which came from an animal. It's all mixed together / fungible. Nevertheless, there's an important distinction here, because emissions from food are fundamentally limited by how much food we can produce, so it's carbon balanced on an extremely short time horizon. Meanwhile fossil fuel emissions are uncoupled from any sort of sequestration, and if it balances on any time horizon at all it will be a very very very long one.
I'm likewise unsure if it's fair to treat cattle production which did not engage in deforestation (perhaps located on the great plains or similar) the same as cattle production which did. However I find your argument interesting. I will spend more time brooding on it.
This article measures current biomass distribution. Given that Bison herds in North America has reduced from 60 million to 30 thousand, and I suspect other species have seen similar changes, I'm not surprised by the result.
Also as a point of nuance, I'd like to say that I'm sure we have actually increased biomass density. If we had not, our farms wouldn't be doing their jobs very well. I'm not trying to say no increase has occurred, simply that it is less than one might expect. Unfortunately I don't have exact numbers to back this up though. I wasn't planning on writing all this when I woke up today, and it's admittedly not my field. Here's to hoping more informed people take over!
Sorry I didn't mean to say that atmospheric methane has not increased. It definitely has, as other commenters have pointed out. However, I contend that most of this increase is likely from other factors. Melting of the polar ice caps, factory emissions, etc.
A common misconception which I frequently see when this topic arises is the failure to distinguish carbon cycles and one-way carbon emission.
You exhale carbon dioxide. However, this carbon dioxide comes from the carbon in the food you eat, and the food you eat obtained it from the atmosphere. Thus, it's a cycle. As a system (ignoring food transportation, deforestation, etc.) it's effectively carbon neutral.
By contrast, when we dig up oil and burn it, there is no cycle. It's a one way street.
Methane production from cattle is slightly more complicated instance of a carbon cycle. The cows produce methane, which is a more potent greenhouse gas than carbon dioxide. However, it degrades in the atmosphere into C02. Since this C02 was obtained from the food the cattle ate, this is another cycle.
Since the methane released from cattle is continually degrading, it does not accumulate. The total amount of bovine methane resident in the atmosphere is ultimately a function of herd size, or perhaps more accurately quantity of feed consumed.
You may be surprised to learn that cattle herd size has remained relatively stable over time. Additionally our planet was once host to wild ruminants like Buffalo which no longer exist in large numbers. As a result I would be very surprised to learn that bovine methane production is completely out of historical context.
As a result I see this as a topic which generally serves to distract from the root cause and real problem associated with climate change - fossil fuel usage.