Paul and I have been hard at work on our book
. We have one little section of one chapter left to write. Just a little section, but one that seems super important so we're spending a lot of time trying to get it right.
One of the big problems that we tackle in the book is carbon footprint. We talk about solutions that we can implement at home and in our backyard that make a huge impact in this space. Solutions that could go so far as to entirely offset our carbon footprint. Or even put it in the minus.
Paul and I recently watched "Cowspiracy." In this movie they suggested that the #1 best thing you can do for the environment is to become a vegan. I think that the movie raised some very good points, but I also think that it drew the wrong conclusions from those points.
Before I go any further, I want to say explicitly that I am totally 100% okay with it if people choose to eat a vegan diet. No problem. That's going to be the best option for some people - for all sorts of reasons. On the other hand, I think that it is not going to be the best option for all people - for all sorts of reasons. So let's explore how a vegan can lower their carbon footprint and how an omnivore can lower their carbon footprint without becoming a vegan.
Maybe someone will someday throw millions of dollars at in-depth (somehow unbiased) research into this. Until then, please excuse me while I ramble away with some numbers, some of which might be a bit squishy.
The biggest claim made in the movie was that livestock and their byproducts cause at least 51% of all greenhouse gas emissions worldwide. I have all sorts of things I wish to say about this, but instead I want to share a quote from this article
which is written by Danny Chivers, a climate change researcher who is also a vegan:
There’s only one problem with this eye-grabbing stat: it’s a load of manure. Emissions from livestock agriculture – including the methane from animals’ digestive systems, deforestation, land use change and energy use – make up around 15 per cent of global emissions, not 51 per cent. I’ve been vegan for 14 years and have been asked to justify my dietary weirdness at more friend and family meals than I can count, so believe me – I’ve looked into it. If meat and dairy really were the biggest cause of global climate change I’d be trumpeting that statistic myself every chance I got.
There were a whole bunch of other numbers shared during the movie but it felt like the main thrust of the whole argument was this 51% figure. So it seems to me that it's a bit of a blow to their argument to say that their big point was drastically exaggerated by a factor of more than 3.
A big point that they were making in the movie is that everyone is focused on fossil fuels and reducing fossil fuels to reduce carbon footprint. And they were trying to point out that no one ever brings up animal agriculture, which they claimed was an even bigger factor. I think that we've already seen that there are some issues with the numbers, but I think it's good to remember as well that a lot of the emissions from conventional animal agriculture are also from fossil fuels used for feed production and transportation.
Still, even though I disagree with their numbers, I am thankful that they are trying to draw attention to the fact that our food has a footprint. Because that's not talked about nearly often enough. In this thread
I talked about how, after many hours of debate, Paul and I agreed that if you consider all direct and indirect sources, food might make up 35% of all carbon emissions, which I think does put food at the #1 most important thing to work on - just not in the way that the movie suggests.
The average adult footprint in America is 30 tons. 35% of that is 10.5 tons. Given the significant proportion of people who follow the Standard American Diet (SAD), I think it is fair to say that the food footprint of the average person on the SAD is 10.5 tons per year.
Next, let’s look at the vegan diet, keeping in mind that a vegan diet can consist of diet cola and “cookies” just as much as the SAD. It just swaps out animal products for plant-based proteins. One of the more powerful things that some vegans like to point out (though surprisingly Cowspiracy did not), is that with conventional agriculture it takes roughly 10 calories of animal feed to produce 1 calorie of animal food. And that feed has roughly the same direct footprint as conventional agriculture-raised human food.
To massively oversimplify, let’s say that 30% of an omnivore’s diet comes from animal products. That way, if a vegan diet is 100 units of footprint, an omnivore diet is 70 + 10*30 = 370 units of footprint. The direct (and some of the indirect) footprints are almost 4 times greater! Unfortunately, a huge portion of food footprint comes from indirect sources, most of which are not significantly affected by whether or not the food is animal-based or plant-based. Looking at the figures and trying to be generous in the direction of the vegans, my rough estimate would be that switching from the SAD to a vegan diet could cut up to 15% off of the average overall footprint - nearly half of the average food footprint! So where the food footprint of the SAD is 10.5 tons per year, the food footprint of the vegan diet would be around 6 tons per year. That’s pretty significant!
Of course, we can do better than that…
Let’s look at “next step” for omnivores - pastured meat. I’m going to oversimplify by focusing on cows. Researching for this book, I read a section written by Eric Toensmeier in Steve Gabriel’s book “Silvopasture: A Guide to Managing Grazing Animals, Forage Crops, and Trees in a Temperate Farm Ecosystem.” In this section, Mr. Toensmeier shared that there is a lot of skepticism of some of the big claims of managed grazing and silvopasture. To illustrate the points he was making, he chose to use numbers that were 10 times smaller and closer to the “accepted” numbers with the hopes that maybe someday we’ll have enough evidence that it is indeed way better. I’m choosing to do the same here. Using data that Mr. Toensmeier shared from the IPCC in that section, I believe that by switching from grain fed to managed grazing, each person can sequester roughly 0.4 tons of CO2 per year. PLUS! We can also remove almost all of the direct and many of the indirect footprints of raising grain fed animals. Taking these things into consideration, and trying to be conservative, I think that an omnivore eating the SAD except with well managed pastured meat (still bought from a supermarket) would weigh in with a diet footprint of around 4.5 tons per year.
But wait, there’s more! This is permies. This is where we talk about permaculture and working in a symbiotic relationship with nature. It is true that today it’s hard to find permaculture food at the grocery store, but I dream that I may live to see such a day come. As we were working on the book we wanted a new word to label food that is “permaculture food”… but that means a lot of different things to different people. So we came up with “Virgin and strictly Organic and Rich soil and Polyculture/Permaculture” (VORP). And since we made the word up we get to define what it means!
- low processing, low packaging
- foods are grown in aged soil with a high organic matter level
- polyculture of at least 12 species
- harvested with minimal soil disturbance
- harvested by hand (no harvesting by machine)
- human to acre ratio is very high: more like gardening than farming
- super localized inputs
- minimal irrigation
- seasonal foods
- minimized grafting
- super localized plant and animal varieties
- no cardboard or newspaper in horticultural endeavors
- no pesticides, even OMRI approved pesticides
- growing plants in a space that suits them as opposed to adding fertilizers and using pesticides to force an artificial environment
- pampered animals (bye bye CAFO)
Let’s talk about a world where VORP food is available at the grocery store. I imagine VORP food would come out of something that at least somewhat resembles silvopasture. Silvopasture sequesters at least 3 times the carbon as managed grazing alone, so rather than 0.4 tons of CO2 sequestered per person, we’d be looking at something closer to 1.2 tons. The net direct emissions would be -1.2 tons per person. Further, there would be many further reductions in the indirect emissions category. I think that a person buying VORP food at the grocery store would have a food footprint of around 2 tons per year.
Time to return to the vegans. A vegan diet bought from the store might be around 6 tons per year. If instead vegans would grow most of their own food in their backyard, even if they still use petroleum-based machinery and fertilizers and pesticides and such (all permitted under the vegan umbrella), they will have eliminated a huge portion of the indirect footprint of their diet. So much so that their food footprint could reasonably be less than half a ton per year!
But of course at permies we are trying to get away from all that petroleum-based machinery and fertilizers and pesticides and such. And it gets really cool when you look at the potential footprint of an omnivore’s VORP forest garden… -1 tons per person! Yes that’s right, net sequestration!
|diet||CO2 equivalent footprint (in tons)|
|SAD - purchased||10.5|
|vegan - purchased||6|
|SAD w pastured meat - purchased||4.5|
|VORP omni - purchased||2|
|VORP omni forest garden||-1|
Rather than switching to a vegan diet to lower your carbon footprint, it would be far more impactful to grow your own food.