Read on Twitter
Here's the Michigan University study that came up in the recent (overblown) #Biden/ #beef controversy: http://css.umich.edu/sites/default/files/publication/CSS20-01.pdf What would the carbon footprint reduction be when Americans would reduce beef intake with 90% (VERY hypothetical)?
Let's look at the numbers... THREAD
Let's look at the numbers... THREAD
Here are the scenarios (converted to yearly data):
- baseline: Americans diets = 1.8 tCO2-eq/p/y
- halving animal foods = ?
- additional reduction of beef to 10% = ?
- baseline: Americans diets = 1.8 tCO2-eq/p/y
- halving animal foods = ?
- additional reduction of beef to 10% = ?
Here are the predicted savings (per person, per year):
- halving animal foods = 1.2 t CO2-eq/p/y --> -0.6 t
- + beef restriction (to 10%) = 0.9 t --> -0.9 t
- halving animal foods = 1.2 t CO2-eq/p/y --> -0.6 t
- + beef restriction (to 10%) = 0.9 t --> -0.9 t
In other words, on a TOTAL carbon footprint of 17 t CO2-eq/p/y for an average American, the dietary change would result in a % saving of:
- halving animal foods: 4%
- + beef restriction (to 10%): 5%
- halving animal foods: 4%
- + beef restriction (to 10%): 5%
On aggregate, this would mean a 224/330 MMT saving for the entire US, which on a TOTAL CO2-emission output of 6600 MMT equals 3-5% savings in national emissions.
This, by the way, is not all that far from the estimate by White & Hall in their 2017 PNAS modelling paper, using a different methodological perspective: if we would make the US livestock free, emissions would drop with some 3%.
https://www.pnas.org/content/114/48/E10301
https://www.pnas.org/content/114/48/E10301
Time & again, studies report the same footprint reduction for Western diets that severely restrict meat & dairy: 1-6%
Something, but not really a game changer. Plus, it undermines food traditions & the restrictiveness may come with nutritional trade-offs.
https://aleph-2020.blogspot.com/2019/06/greenhouse-gas-emissions.html
Something, but not really a game changer. Plus, it undermines food traditions & the restrictiveness may come with nutritional trade-offs.
https://aleph-2020.blogspot.com/2019/06/greenhouse-gas-emissions.html
Moreover, these calculations are based on several assumptions that need there own contextualization. An overview can be found here: https://aleph-2020.blogspot.com/2019/06/greenhouse-gas-emissions.html
If you read all of the above, you'll see that the "cows vs cars" comparison that the folks from Minnesota University are making in their document is very misleading. And yet, this comparison is recycled over & over again as a slogan, especially by people with anti-livestock bias.
