4 ms·

Meat farming takes in CO2 (photosynthesis), and produces CO2 (cows breathing) and CH4 (cows farting). CH4 is a much more potent greenhouse gas than CO2, so, eve

Meat farming takes in CO2 (photosynthesis), and produces CO2 (cows breathing) and CH4 (cows farting). CH4 is a much more potent greenhouse gas than CO2, so, even by your flawed simplified model, farming cows has a net negative greenhouse effect.

ravenstine 4y ago
So what if methane is more "potent"? How potent and in relation to what, and in what amount? Large ruminants and other animals that produce methane roamed the Earth in greater numbers long before humans came up with the concept of livestock. Stable isotopes of carbon in atmospheric methane don't support livestock being a contributor to rising methane at all. Because livestock methane is part of the carbon cycle, and livestock aren't in greater numbers, problematic increases in atmospheric methane have to be coming from somewhere else, most likely things such as fracking. Carbon-14 would be increasing in the atmosphere if cows were responsible. Even if we eliminated meat consumption, hypothetically speaking, it's totally unclear and unfounded that any meaningful difference would be made. According to the United States EPA, agriculture as a whole makes up 11% of greenhouse gas emissions in the United States. That percentage includes everything from farm to table, meaning that cows in particular make up a fraction of that since most of the greenhouse gas will inevitably come from transportation and processing. Methane itself makes up ~11% of greenhouse gas. Show me any evidence whatsoever that correcting for the greenhouse gas from animals bred for food will make any appreciable difference in changing the climate in the favor of humans. By the way, most of the methane from cows comes from their burping, not farting.
- IanCal 4y ago
  > So what if methane is more "potent"? If you are concerned about global warming, swapping one thing for something else that has a greater negative impact is bad. Having a process or animal that converts CO2 to methane is not neutral just because the CO2 was already in the atmosphere. > How potent 25x more. > and in relation to what, CO2 over a period of 100 years usually. > and in what amount? Any amount, it's a relative figure.
  - snovv_crash 4y ago
    Doesn't methane break down much more rapidly than CO2?
    - rbanffy 4y ago
      Yes. And it turns into, guess what, CO2. And heat.
    - dagss 4y ago
      The 25x number already includes this effect. Methane is much much more potent than CO2, but since it breaks down rapidly then over the course of a 100 years the average effect is 25x. So: if you first say "25x" then you cannot say "break down" afterwards because that is included in the 25x, you are then mentally including the breakdown twice. There are also higher numbers in use than 25x that is used for the effect over shorter horizons. But 100 years seems like a good horizon for the humanity getting through the crisis or not.
- dagss 4y ago
  Total emissions of 100% is made up contributions of 1%+1%+1%+... By that logic there exists nothing that can help climate change...even if we are causing it. A bit like saying "shooting this one plane down out of 1000 enemy planes does not win the war; may as well not shoot it and give up". Yes, obviously if we had never touched fossil fuels, having even more lifestock than today would probably be fine too, but that is not very relevant.
tomp 4y ago
CH4 has a half life of like 10 years or so, so even if you deleted all cows from the world right now, in 20-40 years you'd be back to "only fossil fuel CO2 causing climate change". Furthermore, has CH4 from cows even increased historically? There are 30m cows in the US, compared to 60m bison 150 years ago.
- dagss 4y ago
  2 things: A common error about CH4 is misunderstanding half-life vs CO2e calculations. The half life is 10 years but that does not make it a non-problem; a commonly used number is that CH4 is 25 more potent that CO2 -- but that number 25x is OVER A 100 YEAR LIFESPAN that already INCLUDES the decay over those 100 years. So if you mention that half year is 10 years you also throw the number 25x out the window, then the multiplier is much much larger (forgot how much). Because of this scientists use different potebtial multiplier for CH4 for different time horizons. Anyway it IS a problem to have CH4 instead of CO2, how big a problem depends on your time horizon and over 100 years CH4 is 25x worse than CO2 INCLUDING decay. You touch on the second point already. As long as lifestock is constant, CH4 is constant at a certain level. Still: Reducing lifestock will reduce CH4 to a lower constant level which will reduce greenhouse effects as CH4 decays to a lower stable level where emission and decay balance. In a sense, reducing lifestock is the same as CO2 capture -- not the same as stopping to burn fossils.
  - tgb 4y ago
    My understanding is that CH4 breakdown in the atmosphere isn’t a matter of exponential decay either but is (or could become) rate limited by OH radical availability. Such that the half life increases as more is in the atmosphere and it’s possible to totally outpace the breakdown even at constant emissions. https://en.m.wikipedia.org/wiki/Atmospheric_methane https://en.m.wikipedia.org/wiki/Atmospheric_methane
koide 4y ago
It's not farting, it's belching. Can be ameliorated adding algae to the feed. It's not very relevant to the point you're making in this case, but it's good to be precise and also might help you revisit your sources if you just didn't misspeak. https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-source-cow-belching-or-cow-flatulence/ https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-so... https://www.industry.gov.au/data-and-publications/from-beaches-to-burps-native-australian-seaweed-key-to-reducing-methane-emissions-from-cows https://www.industry.gov.au/data-and-publications/from-beach...
- myshpa 4y ago
  Also poop.

ravenstine 4y ago

So what if methane is more "potent"? How potent and in relation to what, and in what amount? Large ruminants and other animals that produce methane roamed the Earth in greater numbers long before humans came up with the concept of livestock. Stable isotopes of carbon in atmospheric methane don't support livestock being a contributor to rising methane at all. Because livestock methane is part of the carbon cycle, and livestock aren't in greater numbers, problematic increases in atmospheric methane have to be coming from somewhere else, most likely things such as fracking. Carbon-14 would be increasing in the atmosphere if cows were responsible. Even if we eliminated meat consumption, hypothetically speaking, it's totally unclear and unfounded that any meaningful difference would be made. According to the United States EPA, agriculture as a whole makes up 11% of greenhouse gas emissions in the United States. That percentage includes everything from farm to table, meaning that cows in particular make up a fraction of that since most of the greenhouse gas will inevitably come from transportation and processing. Methane itself makes up ~11% of greenhouse gas. Show me any evidence whatsoever that correcting for the greenhouse gas from animals bred for food will make any appreciable difference in changing the climate in the favor of humans. By the way, most of the methane from cows comes from their burping, not farting.

IanCal 4y ago
> So what if methane is more "potent"? If you are concerned about global warming, swapping one thing for something else that has a greater negative impact is bad. Having a process or animal that converts CO2 to methane is not neutral just because the CO2 was already in the atmosphere. > How potent 25x more. > and in relation to what, CO2 over a period of 100 years usually. > and in what amount? Any amount, it's a relative figure.
- snovv_crash 4y ago
  Doesn't methane break down much more rapidly than CO2?
  - rbanffy 4y ago
    Yes. And it turns into, guess what, CO2. And heat.
  - dagss 4y ago
    The 25x number already includes this effect. Methane is much much more potent than CO2, but since it breaks down rapidly then over the course of a 100 years the average effect is 25x. So: if you first say "25x" then you cannot say "break down" afterwards because that is included in the 25x, you are then mentally including the breakdown twice. There are also higher numbers in use than 25x that is used for the effect over shorter horizons. But 100 years seems like a good horizon for the humanity getting through the crisis or not.
dagss 4y ago
Total emissions of 100% is made up contributions of 1%+1%+1%+... By that logic there exists nothing that can help climate change...even if we are causing it. A bit like saying "shooting this one plane down out of 1000 enemy planes does not win the war; may as well not shoot it and give up". Yes, obviously if we had never touched fossil fuels, having even more lifestock than today would probably be fine too, but that is not very relevant.

tomp 4y ago

CH4 has a half life of like 10 years or so, so even if you deleted all cows from the world right now, in 20-40 years you'd be back to "only fossil fuel CO2 causing climate change". Furthermore, has CH4 from cows even increased historically? There are 30m cows in the US, compared to 60m bison 150 years ago.

dagss 4y ago
2 things: A common error about CH4 is misunderstanding half-life vs CO2e calculations. The half life is 10 years but that does not make it a non-problem; a commonly used number is that CH4 is 25 more potent that CO2 -- but that number 25x is OVER A 100 YEAR LIFESPAN that already INCLUDES the decay over those 100 years. So if you mention that half year is 10 years you also throw the number 25x out the window, then the multiplier is much much larger (forgot how much). Because of this scientists use different potebtial multiplier for CH4 for different time horizons. Anyway it IS a problem to have CH4 instead of CO2, how big a problem depends on your time horizon and over 100 years CH4 is 25x worse than CO2 INCLUDING decay. You touch on the second point already. As long as lifestock is constant, CH4 is constant at a certain level. Still: Reducing lifestock will reduce CH4 to a lower constant level which will reduce greenhouse effects as CH4 decays to a lower stable level where emission and decay balance. In a sense, reducing lifestock is the same as CO2 capture -- not the same as stopping to burn fossils.
- tgb 4y ago
  My understanding is that CH4 breakdown in the atmosphere isn’t a matter of exponential decay either but is (or could become) rate limited by OH radical availability. Such that the half life increases as more is in the atmosphere and it’s possible to totally outpace the breakdown even at constant emissions. https://en.m.wikipedia.org/wiki/Atmospheric_methane https://en.m.wikipedia.org/wiki/Atmospheric_methane

koide 4y ago

It's not farting, it's belching. Can be ameliorated adding algae to the feed. It's not very relevant to the point you're making in this case, but it's good to be precise and also might help you revisit your sources if you just didn't misspeak. https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-source-cow-belching-or-cow-flatulence/ https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-so... https://www.industry.gov.au/data-and-publications/from-beaches-to-burps-native-australian-seaweed-key-to-reducing-methane-emissions-from-cows https://www.industry.gov.au/data-and-publications/from-beach...

myshpa 4y ago
Also poop.