Differences in the carbon footprint of different foods (2020) | Hacker News Reader

Differences in the carbon footprint of different foods (2020)

ourworldindata.org

Reading the article, I thought that it was not relevant to compare carbon footprint per unit of mass, and I was pleased to see it was addressed in the last section. However, the way it's addressed feels even more disingenuous: they removed all the non protein-rich food from the chart. Naturally, mostly animal products remain at the top.

Based on the assumption that humans need protein[0], it seems only fair to compare everything we eat on a carbon-cost / protein-value basis without cherry-picking the data points. It's here:

https://ourworldindata.org/grapher/ghg-per-protein-poore?tab...

A few observations: - coffee and chocolate are very high up. To be fair, nobody assumes that those have any kind of nutritional value, and that's not why they are consumed. - beef and lamb are very high. It implies that, even in the most charitable light, lamb and beef are bad in terms of carbon emission[1]. - among non-animal products, tomatoes, cassava and bananas are surprisingly high up. Higher than a lot of animal products. Now that is relevant, because those are consumed for their actual nutritional value. Rice, a staple all around the world, is worse than farmed fish, or eggs! - wheat and nuts have an amazing carbon-cost/nutritional value ratio.

[0] and fat, there are no essentials carbs. [1] and that makes me sad because I love both.

Coffee is also consumed ~20g at a time

the fact chocolate & coffee consumption are not primarily for nutrition make their impact even worse

and for proteins & fat, maybe I'm not human, or maybe rice have enough for me, but I don't eat animal food more than a few times a year, rest of the time I eat rice and plenty vegetables, so that's just to put a nuance on the "you need a daily meat intake" common falsy recommandation

Why is the title phrased as a question? It's not like carbon footprint is a directly measured value that takes investigation to figure out where it came from, it's something that's calculated and you can just look at what went into the calculations.

Cows and ruminants have been roaming the Earth for a long time. If they were a huge contribute to global warming, it would be pretty hot already. Focusing on methane emission omits the fact that grasslands absorb carbon dioxide from the atmosphere, and that a properly managed grassland actually sequesters carbon dioxide. Whereas factory farming breaks this cycle. We need to think in more nuanced ways if we’re going to solve global warming.

https://www.agriculture.com/livestock/cattle/methane-and-gra...

> Cows and ruminants have been roaming the Earth for a long time. If they were a huge contribute to global warming, it would be pretty hot already.

The number of cows has of course massively increased over time.

I’m inclined to think so but wasn’t America full of hundred of millions of bison at one point.

80 million before 1850 according to Wikipedia. Now we're at about 1 billion cows worldwide, so it would depend on the number of cows/bison in the rest of the world at that time.

https://animalclock.org/

As a slight diversion from the carbon focus, the proportion of animals that is cows has increased drastically, as well. Look up the animal biomass proportions. It's shocking (sickening, even) to learn what proportion of the mammal biomass is cows and humans, and what proportion of the animal biomass is cows, chickens, and humans.

I think the major point that people miss is that there is a thing called the "Carbon Cycle"[0] which basically stipulates that all carbon that already exists in the system will continually be transformed into different things and then back into carbon (and the inverse). This is pretty ordinary and cows are a part of that. Though the effects of transforming a lot of carbon at once might be profound and dangerous.

The major issue is that we're digging up shit loads of carbon and releasing it, which is the much more dangerous thing and reframing the argument to be against meat because meat has a carbon cost is like saying that the mountains are causing water levels to rise because "water comes from the mountains" (though, as part of the water cycle).

[0]: https://oceanservice.noaa.gov/facts/carbon-cycle.html

The problem is the animals eating feed grown with fossil fuel derived fertilizers: https://climate.mit.edu/explainers/fertilizer-and-climate-ch...

Cattle eating grass is one thing- industrial feed lots are another and they're needed to produce beef at the scale humans are eating it.

It cant possibly be as simple as that can it?

What’s wrong with banning those feeds and letting the price normalise causing the rate of consumption to drop to sustainable levels?

I must be missing something?

You're missing politics.

Oil+gas companies, and fertilizer producers, are deep in the supply chain and are thus embedded in the governing bodies (because no country is very good at preventing corruption). Things only change when those companies let them change.

that. is… upsetting.

The people that like cheap meat won't like that, a lot.

Ag lobbies are powerful enough no one in the US would dare propose anything like that. Even in climate conscious EU a much more modest, roundabout way of addressing part of the problem of ag emissions (nitrate levels) has been met with massive farmer protests.

Have cows been fed corn for thousands of years too? Most nitrogen that is bio available today stems from human fertilizer production [0]. Its the only thing allowing orders of magnitude more human, cows and farmland in the first place to exist. No natural fixation process can hold up with human output of carbon gases.

[0] veritassium video about german haber-bosch process, which is the basis for 2/3 of humans existing today. Fuck jesus, these guys are your literal daddies!!

sometimes people forget the quantity of farm animals nowadays: https://ourworldindata.org/wild-mammals-birds-biomass#:~:tex.... it's nothing close to natural anymore

In response of a recent post about Perennial rice and its top comment: https://news.ycombinator.com/item?id=35483071

Other relevant article: https://www.euronews.com/green/2023/03/07/meat-diary-and-ric...

“Methane has a much shorter atmospheric lifetime than carbon dioxide (CO2) – around 12 years compared with centuries – but absorbs much more energy while it exists in the atmosphere”

https://www.iea.org/reports/global-methane-tracker-2022/meth...

>Methane has a much shorter atmospheric lifetime than carbon dioxide

And after that it continues as carbon dioxide (and water).

Reasoning from first principles (physics), there is zero CO2 impact of food, including beef (especially discounting methane).

Animals are part of the CO2 cycle. They breathe out CO2, you eat meat and breath out CO2, grass consumes CO2 to grow, cow eats grass - loop complete.

Of course, there are other inputs - e.g. transportation and fertilizer production (fun fact: 50% of the protein of your body is artificially produced, organic nitrogen bound via Haber-Bosch process).

But those are energy inputs, not CO2 inputs. If we used nuclear/solar, farming would be CO2-neutral.

All long-term climate change impact is coming from fossil fuels, not meat/farming. (Methane has only short-term impact.)

Nuclear/solar is not going to solve deforestation.

It won't, but economic progress will.

Most rich countries are increasing forest (reforesting, not deforesting).

it's more like a side-effect of lower fertility, because 1 person in rich country pollutes as much as 40 persons in poor countries

It's interesting to understand the impact across different food types but this type of infographic is kind of misleading when you look at emissions by sector.

The whole of agriculture related emissions pales in comparison with the emissions from coal/natural gas plants or steel industry emissions.

It's ok to not eat meat for animal welfare but to spin it for emission purposes is misleading. You would have a greater impact for the environment by not using your car, not using AC in the summer, midly heating your home in the winter, stop buying trinkets from Amazon, etc.

> You would have a greater impact for the environment by not using your car, not using AC in the summer, midly heating your home in the winter

I agree with some of this. But not having cooling or heating will make the civilization existence in many parts of the world nearly impossible. India(and probably other Asian countries) is a prime example.

At least a few years ago, 90%+ (probably even 95%+) of people in India didn't have AC, so not having cooling clearly does not make the existence of civilization impossible there.

1. The temperatures are going to get higher, and nothing is going to reverse the trend in the near future.

2. Yes, people can survive. But I assume most time is spent surviving instead of living. You can’t be very productive at 35+ degrees.

3. Many people in India survive without a toilet. Doesn’t mean it’s how it should be. And their lives will be much better if they didn’t have to defecate on the streets. I’d argue same applies to ACs.

> not using AC in the summer

Can you expand on this?

AC is 100% matched by the curve of solar energy input (sun -> heat -> AC cooling but also sun -> solar power), so presumably as we transition towards more and more solar, we should be using AC more.

AC is still using a lot more energy (x50-x100) than a basic fan

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