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In this article and many others, I read that cows are contributing to the climate change more than cars in releasing CO2.

A United Nations report has identified the world's rapidly growing herds of cattle as the greatest threat to the climate, forests and wildlife.

If this is true humans shouldn't be blamed for the climate change. I understand we grow them for meat so it's again us. But if we would let the cows overpopulate we would end up with the same result.

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    You should make this question more clear. With cows, methane is a major issue. So you have to be clear if you mean purely CO2, or gases weighted by atmospheric forcing. And do you mean all cars versus all cows world-wide, or just in New Zealand? – DavePhD Jun 23 '17 at 19:18
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    It's not that cows would be contributing to climate change by growing in population if we weren't eating them; they would just not exist. Cows are domesticated animals and would not survive without the agricultural supports we give them. Raising cows contributes to global warming through methane and deforestation. – antlersoft Jun 23 '17 at 19:22
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    @antlersoft, good point! – Grasper Jun 23 '17 at 19:23
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    @Grasper - For updated poster, note that while methane 504 lbs of methane in the atmosphere has heat trapping power of nearly 12,000 lbs of C02, methane doesn't stay in the atmosphere very long compared to CO2, so the total heat trapped by the incremental CO2 will be greater. Both agriculture and fossil-fuel use contribute to global warming; a significant part of the impact of agriculture isn't emissions per se but the attendant deforestation, which degrades a valuable carbon sink. – antlersoft Jun 23 '17 at 19:56
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    The title and the body currently have different claims. Do cows produce more CO2 than cars? Straight forward. Do cows contribute more to greenhouse warming than cars? Much more complicated, as you have to look at the whole cycle. Cows make CO2 from digesting grass, which removes CO2 from the atmosphere to grow. Cars make CO2 from fossil fuels, which were created millions of years ago. That carbon was not in the atmosphere for a long time. And of course methane is its own issue. – Brythan Jun 24 '17 at 3:32
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TLDR: Yes. Cows produce around 9.5% of human originated pollution, or greenhouse gases (GHGs), while cars produce around 8.5% of human originated GHGs. This does not mean that humans shouldn't be blamed for climate change, however, as 85.5% of GHGs do not come from domestic animals.


Regardless of whether two cows produce as much greenhouse gas as a car, we have a lot of other polluters:

Let's take a look at the United States according to the US's EPA: US Greenhouse Gas Emissions 2015

Digging down further into their numbers for Agriculture, enteric fermentation ("cow belching", or more accurately, all livestock emissions) makes up one third of the numbers for "Agriculture", which in the US is only 9% of the greenhouse emissions. Mostly it's farming that introduces greenhouse gases in agriculture.

If we look at the worldwide emissions, also on the EPA's site:

enter image description here

Here, agriculture & forestry together produce less than a quarter of pollution, and that includes deforestation.

They also note that, while they don't include it in the graph, the biosphere, or natural carbon cycle, offsets only 20% of the agricultural output, or 4.8% of anthropogenic GHGs. I shall not include it in my calculations as it is a global effect, not specific to cows.

According to the Food and Agricultural Organization of the United Nations, Livestock in its entirety produces 14.5% of total greenhouse gas emissions, as opposed to transportation (car, truck, airplanes) taking 14%. It also notes that cows are responsible for 65% of those emissions, for a total of 9.45% of emissions. As for cars, according to the EPA once again, "light duty vehicles" (ie, cars) make up 61% of transportation emissions, for a total of 8.54% of total emissions. So in that view, yes, cows produce more total emissions than cars, but this doesn't mean that cows are more to blame than humanity for climate change.

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    @jeffronicus That includes feed production and land change, as well as enteric fermentation and manure, and processing of the animal products. About 94% of the livestock number is "sitting around in a meadow participating in our doom", though, through eating, flatulence, manure, and exhaling. 6% is in processing, and 45% is simply in feeding them, with 39% is cow emmissions and 10% is cow excretions. – Kevin Fee Jun 23 '17 at 20:31
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    This answer is wrong (and the "explanation" in the question is intentionally designed to mislead). What cows and other animals (including humans) produce is part of the natural carbon cycle, which is stable over the long term. (That is, critters have been exhaling for hundreds of millions of years, without causing problems.) What cars emit is produced from buried carbon (unless you run on biofuel of some sort), and so is ADDING CO2 to the atmosphere. – jamesqf Jun 24 '17 at 4:44
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    FYI, when I read "pollution" I don't think "CO2", I think "NOX". (I've never thought of cows as pollution agents.) A more accurate term might be better... – Mehrdad Jun 24 '17 at 8:32
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    @jamesqf You are incorrect. As I noted from the EPA website, 20% of human agriculture output is offset by the natural carbon cycle. We aren't adding trees or other CO2 scrubbing organisms to offset our increase in animals. In fact, we're taking them away. In the past, when there were more "critters" that produced more CO2, it provided more for the CO2 scrubbers to feed on, and so they flourished. We've been doing our best to curtail them because they encroach on our space. – Kevin Fee Jun 26 '17 at 15:06
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    @AndrewGrimm Good point, it's actually about any and all emissions, but it is usually called cow burps. Fixed. – Kevin Fee Jun 26 '17 at 15:24

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