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Livestock emissions form a cycle. If you literally killed and deleted all cows from the planet, you’d get a slight delay in global warming, but wouldn’t solve

• etrautmann 4y ago
  your comment suggests a misunderstanding. Cows convert inert carbon from feed into methane, a much more potent greenhouse gas. Not all carbon is created equal from the perspective of climate. While you're correct that fossil fuel control is crucial, livestock emissions are also an important part, and it's a false dilemma to solely focus efforts on one issue.
  • tengbretson 4y ago
    You are not looking at the cycle in its entirety. Cows convert carbon from their biomass feed into methane as a part of digestion, but absent the cow, that same biomass would still at some point decompose on its own, releasing methane in the process.
    • virgildotcodes 4y ago
      Doesn't this presume that we would continue to grow the same amount of feed and then allow it to decompose? Whereas a reduction in meat consumption would mean a reduction in total global land use for agriculture, allowing that land to be rewilded. Trapping carbon over a longer term and potentially providing numerous environmental benefits.
      • kebman 4y ago
        It's grass. If you stop growing grass, something else will grow in its place.
        • deleted 4y ago
          [deleted]
        • virgildotcodes 4y ago
          The vast majority of cattle are raised on grain, not grass. "The researchers report that grass-fed beef contributes very little to the global protein supply, accounting for just one gram of protein, per person, per day. In comparison, ruminants as a whole contribute 13g of protein to the global average protein intake, per person, per day." "Despite making only a marginal contribution to global protein intake, grazed beef accounts for between a quarter and a third of all greenhouse emissions from ruminant livestock." https://tabledebates.org/sites/default/files/2022-04/fcrn_gnc_report.pdf https://tabledebates.org/sites/default/files/2022-04/fcrn_gn... A related interesting fact - 77% of the world's soy is used for feed: https://ourworldindata.org/soy#:~:text=The%20majority%20(77%25)%20of,processed%20into%20soybean%20'cake' https://ourworldindata.org/soy#:~:text=The%20majority%20(77%....
        • rafaelero 4y ago
          This is a very inaccurate picture. Only a minority of cows are grass-fed [1]. [1] https://extension.sdstate.edu/grass-fed-beef-market-share-grass-fed-beef#:~:text=About%204%25%20of%20U.S.%20beef,value%20of%20roughly%20%244%20billion https://extension.sdstate.edu/grass-fed-beef-market-share-gr....
          • nightski 4y ago
            Right but that likely means grass finished? Because from what I understand most U.S. beef is grass fed and then finished at feed lots.
            • virgildotcodes 4y ago
              Thank you, I actually didn't know this! I'd always heard about the proportion of animals that were raised on grain, as well as the percentage of crops used for animal feed, and concluded that in the US at least the majority of cattle were raised in feedlots their entire lives. Turns out you're right, the majority start out on pasture and then are transported to feed lots to fatten up once they reach maturity. According to this[1], due to the fact that grass fed beef fatten up more slowly, end up at a lower overall weight at slaughter, and are kept alive and emitting longer, "a nationwide shift to exclusively grass-fed beef would require increasing the national cattle herd from 77 to 100 million cattle, an increase of 30%", and "the current pastureland grass resource can support only 27% of the current beef supply (27 million cattle)". Further - "Emissions of methane, a greenhouse gas with a large warming effect relative to carbon dioxide per molecule, come from beef cattle in the forms enteric fermentation and manure emissions. We calculated a 43% increase in methane from enteric fermentation (table 2), assuming that cattle finishing on grass had the same daily methane emissions as present-day stocker cattle, who have nearly identical ADG and are fed primarily on roughage." Either way it seems as if grain is an indispensable part of animal agriculture currently, so we have to take that into account when talking about what would happen to land use with or without the cows around. Additionally, it seems that moving away from grain would potentially have even worse impacts on the climate. [1]https://iopscience.iop.org/article/10.1088/1748-9326/aad401 https://iopscience.iop.org/article/10.1088/1748-9326/aad401
      • towaway15463 4y ago
        You’re assuming the current owners of the land are also going to disappear? If not then why wouldn’t they use the land for other productive purposes. If it’s currently farm land then they would simply change crops. Or maybe they would sell it to a developer who will build a car dependent suburb.
        • virgildotcodes 4y ago
          If they could find other productive purposes sure, but the point of the change from the environmental perspective is that it would reduce demand for agriculture as a whole, that's the heart of why it would be such a big boon for the environment. According to the FAO[1], grazing land for animals and cropland dedicated to producing animal feed represent almost 80% of all agricultural land globally. "Feed crops are grown in one-third of total cropland, while the total land area occupied by pasture is equivalent to 26% of the ice-free terrestrial surface" Given food conversion ratios[2], where you lose roughly 90% of the energy you put into each step up the food chain, the lower we eat on it the lower the amount of energy input we need, which at the bottom of our food chain are those crops and grasslands. Once we remove the heavily inefficient middlemen which are animals, we are left with a drastic reduction in the amount of agricultural land and output needed. I'm not sure how many of these companies and farmers could find another use for their grassland and farmland, as it's not like people will be able to just up their consumption of food by several multiples, and I'm not sure what other sort of productive purposes beyond food production the majority would be able to find. So yeah, once there's no demand and it's no longer profitable, a large amount of that agricultural land seems like it would just be allowed to lay fallow or be rewilded, which would be really beneficial to the environment for many reasons.[3] [1]https://www.fao.org/animal-production/en/ https://www.fao.org/animal-production/en/ [2]https://en.wikipedia.org/wiki/Trophic_level https://en.wikipedia.org/wiki/Trophic_level [3]https://www.rewildingbritain.org.uk/explore-rewilding/what-is-rewilding/why-we-need-rewilding https://www.rewildingbritain.org.uk/explore-rewilding/what-i...
    • ufo 4y ago
      IIRC, aerobic decomposition doesn't create as much methane.
    • DennisP 4y ago
      Anaerobic decomposition mostly produces methane, but aerobic decomposition mostly produces CO2. What happens in nature is mostly aerobic. If you have a compost pile, you turn it periodically to keep it aerobic. https://aggie-horticulture.tamu.edu/earthkind/landscape/dont-bag-it/chapter-1-the-decomposition-process/ https://aggie-horticulture.tamu.edu/earthkind/landscape/dont...
    • elil17 4y ago
      It would release a greater portion of CO2 and a smaller portion of methane if converted by anything other than a cow. Plus, if we didn't deforest as much land to support our least efficient farm animals (cows eat 25 calories for every calorie of meat produced, vs 15 for pigs and 9 for chickens), more of that carbon would be sequestered in trees. Obviously this doesn't apply to sustainably raised cows which are fed primarily from naturally occurring pasture land.
      • deleted 4y ago
        [deleted]
      • nightski 4y ago
        We don't really deforest in the U.S. for animals from what I understand. This takes place in places like South America. We could control imports/exports and I'd be all for that. As far as feed though, not all feed is grown exclusively for cattle. I've worked with sugar companies in the past and the by-products of sugar production (molasses, raffinate, etc..) are sold as cattle feed. This is a billion dollar industry. These by-products are being produced regardless of whether we feed cattle or not.
        • elil17 4y ago
          I mean the forestry aspect is only part of it, the methane/CO2 ratio is still a big deal. Import control is an interesting idea, I haven't heard that before.
        • tedivm 4y ago
          We don't anymore, because we already managed a lot of deforesting in our past. > The 2005 (FAO) Global Forest Resources Assessment ranked the United States as seventh highest country losing its old growth forests, a vast majority of which were removed prior to the 20th century.[3] >For the 300 years following the arrival of Europeans, land was cleared, mostly for agriculture, at a rate that matched that of population growth.[7] During the 19th century, while the U.S. population tripled, the total area of cropland increased by over four times, from seventy-six million to three hundred nineteen million acres. For every person added to the U.S. population during this period, farmers put another three to four acres under the plow.[8] This trend continued until the 1920s when the amount of crop land stabilized in spite of continued population growth. As abandoned farm land reverted to forest the amount of forest land increased reaching a peak in 1963 of 753,000,000 acres (3,050,000 km2).[4] It was estimated that there were 1,023,000,000 acres of forest in 1630, compared to 766,000,000 acres in 2012.
    • giantrobot 4y ago
      Cattle feed left to decompose on its own won't release nearly as much methane as the cattle. The methane produced will also end up released over a longer period of time. A ton of methane released in a day is far worse than a ton released over a year.
    • rafaelero 4y ago
      If there were no cows, there wouldn't be so much biomass for feed in the first place.
    • _Algernon_ 4y ago
      Only if it breaks down without oxygen available. Normal decomposition goes directly to CO2
  • sampo 4y ago
    > your comment suggests a misunderstanding. Cows convert inert carbon from feed into methane, a much more potent greenhouse gas. Not all carbon is created equal from the perspective of climate. Your comment also suggests a misunderstanding. Methane has an atmospheric lifetime of only ca. 10 years. A constant source of methane will not lead to increasing atmospheric methane levels, nor to continuous warming. Whereas a constant source of CO2 will.
    • blueflow 4y ago
      > Whereas a constant source of CO2 will. Which Methane is. It decomposes into CO2 and Water.
      • sampo 4y ago
        Yeah, but that is mostly beside the point. In pure carbon, anthropogenic CO2 emissions are about 12 GtC/year, and CH4 emissions (from fossil fuel, agriculture, waste) about 0.27 GtC/year. So CO2 from methane emissions is only 2% of all CO2 emissions.
        • giantrobot 4y ago
          Methane is like 80x worse than CO2 in terms of greenhouse effect. So that 0.27Gt of CH4 has the GHG effect of 22Gt of CO2. When it decomposes to CO2 it then still has the greenhouse effect of gigs tons of CO2.
        • virgildotcodes 4y ago
          Assuming these numbers are correct - given that CH4 traps 80x more heat than CO2 over the first 20 years[1], it would be the equivalent of adding another 21.6 GtC per year for those first 20 years. Over the span of 100 years, that CH4 degrades into CO2 but still ends up trapping 25x more heat than the same amount of CO2 emitted at the outset, resulting in the same impact as releasing another 6.75 GtC/year over the next century. Nothing to dismiss, especially because that extra boost to heating in those first 20 years could be the difference between us hitting various tipping points, like melting permafrost and releasing yet another 185 GtC[2] into the atmosphere, and not. [1]https://climate.mit.edu/ask-mit/why-do-we-compare-methane-carbon-dioxide-over-100-year-timeframe-are-we-underrating https://climate.mit.edu/ask-mit/why-do-we-compare-methane-ca... [2]https://www.carbonbrief.org/imminent-tipping-point-threatening-europes-permafrost-peatlands/ https://www.carbonbrief.org/imminent-tipping-point-threateni...
  • nosianu 4y ago
    I'm talking from the PoV of someone asking a question, rather than making a statement - since I did not study the subject. I merely noticed it on the side, without investigating deeper. What I find missing in all the cow discussions is any mention of the huge number of bovines that roamed suitable areas of the planet, such as the North American plains, before they were mostly killed off and made room for cows. Was the mass slaughter of buffalo that happened on 19th century USA good for climate? --Photo of a gigantic skull pile, https://en.wikipedia.org/wiki/File:Bison_skull_pile-restored.jpg https://en.wikipedia.org/wiki/File:Bison_skull_pile-restored... For how long and how many animals similar to cows were there before we killed them in most places? Why are the cows such a climate catastrophe now, but the previous gigantic wild herds were not? (An actual question, not a rhetorical one, as I said, I did not study or investigate this, only noticed it)? ------------- As far as my thinking goes, the main problem is and has been that we dig up ancient buried biomass (coal, gas, oil). We have an above-ground carbon cycle, and it does not really matter that much if there is stuff burned and carbon shifting around various forms, as long as it's in the above-ground cycle. The problem, to my knowledge, is that we fed gigantic amounts of below-ground carbon into the above-ground cycle. I did not check the numbers (someone, please?), I think below ground we have far more biomass than we could ever plant as forests above ground? That's why I'm not excited about tree-planting projects as "solution". As far as my understanding goes, only a complete shutdown of all coal, oil and gas extraction can even begin to address our problem. And then we still need to get a lot of carbon back underground. Cows act solely within the above-ground cycle, so I don't see them as a valid focus, but as a distraction. My focus would be on the processes that add below-ground carbon to the above-ground cycle. If the above-ground carbon cycle only has prehistoric amounts of carbon to begin with, would cows, burning forests, etc., still be a global climate problem? As far as I know, that's not the case (independent of local deforesting issues, just looking at the "global warming" problem). I know I'm ignoring always present movement - without humans - between above and below ground - only counting safely long-term stored carbon, not sure what those net movements are (without human activity)? I also ignore "details"; such as if carbon is in CO2 or CH4 in the atmosphere. I think that evens itself out longer term and would be enough for an above-ground cycle that is not increased artificially. Our problem is the speed with which we add below-ground sources to the above cycle.
    • 4y ago
  • admax88qqq 4y ago
    A good chunk of the carbon in livestock feed was pulled from the atmosphere via photosynthesis. Hence the "cycle" part of carbon cycle. We're not feeding cows liquified dinosaurs. A grass fed cow is basically carbon neutral. Grass pull carbon from the air, cows eat that carbon turn it into protein, methane, CO2, we eat the protein turn it into more methane, CO2.
    • adhesive_wombat 4y ago
      Neutral in terms of moles of carbon atoms maybe, but not neutral in terms of kg-CO2e (CO2 equivalent), because methane is much, much more potent as as greenhouse gas than CO2. On a 100 year horizon, it's about 30 times worse than CO2, and over 20 years, 80 times worse. Not all carbon is equal.
• OrvalWintermute 4y ago
  > The real and only issue are fossil fuels You're conflating renewables with climate science. Given the planet has been on a global warming trend SINCE the last Glacial Maximum, it is pretty safe to say that fossil fuels has little to do with it. But if you want to make the case for antediluvian petro-economy, I am all ears.
• delecti 4y ago
  It takes a ton of farm equipment to grow all the feed for cow, and they burp out a ton a methane. I think you're understating how much fossil fuel gets used in industrial animal agriculture. If everyone switched every calorie of beef/dairy they consumed with one of chicken/eggs, there would absolutely be a marked decrease in greenhouse gases being added to the atmosphere.
  • krona 4y ago
    This might be true, but without quantifying everything you've said, nobody can make a value judgment. The essential point is that the livestock emissions are already part of the carbon cycle, and don't 'contribute to emissions' in the way most people think, especially activists.
    • blueflow 4y ago
      Cows feed on plants, plants got their carbon from the atmosphere. So all the carbon they emit, technically, got caught in previously. The implication is that cows themselves are carbon neutral, their damage comes from the extra greenhouse effect the carbon has while its methane.
    • delecti 4y ago
      How about this [1], which shows that producing a calorie of beef produces about 7x as much CO2 as one of chicken (not even including methane), and 30x as much CO2 as one of rice. And this [2] which shows that methane emissions are roughly twice as high per calorie from beef vs soy. Also, saying "already part of the carbon cycle" about factory farmed cows is nonsense, because the sum totality of carbon in the atmosphere is the problem being discussed. It's part of the carbon cycle which is currently bad. [1] https://ourworldindata.org/grapher/ghg-kcal-poore https://ourworldindata.org/grapher/ghg-kcal-poore the data looks fairly well sourced [2] https://interactive.carbonbrief.org/what-is-the-climate-impact-of-eating-meat-and-dairy/ https://interactive.carbonbrief.org/what-is-the-climate-impa...
      • paulmd 4y ago
        Rice is nutritiously void though. You can make healthy things with rice, but rice itself (especially polished rice - vs whole) is an extremely poor source of macronutrients. It's more or less straight carbs and starch. As such it's not really the most useful point of comparison to other nutrient-rich foods. A valuable filler/staple certainly, but you can't live on rice alone.
• Mechanical9 4y ago
  Livestock emissions are not a closed cycle in terms of heat. The methane produced by livestock is much more potent of a greenhouse gas than the CO2 captured by the plants grown for livestock. This might not be a big deal normally, but seeing as how we're maintaining at least 500x the normal cow population, it's a big deal now. Fun fact, methane traps so much more heat than CO2, we'd actually be better off burning methane rather than releasing it directly. That's probably not a viable option for livestock, so it seems like reducing livestock is the most viable thing to do. Agreed that fossil fuels are also an issue.
  • cma 4y ago
    Methane eventually degrades from UV, making it a closed cycle. It isn't cumulative like CO2. The half-life in the atmosphere is 9 years.
    • orwin 4y ago
      Degrade into CO2 and H2O at altitude where CO2 actually have an impact.
  • dashundchen 4y ago
    It's also misunderstanding that livestock are not just a simple closed cycle of "soil + sun + water = grass => cow". Modern industrial ag is a chain of fossil fuel inputs via fertilizer to grow soy and corn quickly as possible, to maximize output over what land would naturally support. The vast majority of meat raised in the US is from industrial consolidated feed lots.
• CyanBird 4y ago
  > If you literally killed and deleted all cows from the planet, you’d get a slight delay in global warming, but wouldn’t solve it. Sounds amazing then, let's do it Why would we care for single perfect solutions rather than many small imperfect ones? If anything this would buy us time, that to me sounds amazing