Does a food carbon tax increase animal deaths and/or the total time of suffering of cows, pigs, chickens, and fish? Theoretically, this is possible, as a carbon tax could lead consumers to substitute, for example, beef with chicken. However, this is not per se the case, as animal products are not perfect substitutes.

I'm presenting the results of my master's thesis in Environmental Economics, which I re-worked and published on SSRN as a pre-print. My thesis develops a model of animal product substitution after a carbon tax, slaughter tax, and a meat tax. When I calibrate^[1] this model for the U.S., there is a decrease in animal deaths and duration of suffering following a carbon tax. This suggests that a carbon tax can reduce animal suffering.

Key points

Some animal products are carbon-intensive, like beef, but causes relatively few animal deaths or total time of suffering because the animals are large. Other animal products, like chicken, causes relatively many animal deaths or total time of suffering because the animals are small, but cause relatively low greenhouse gas emissions.
A carbon tax will make some animal products, like beef, much more expensive. As a result, people may buy more chicken. This would increase animal suffering, assuming that farm animals suffer. However, this is not per se the case. It is also possible that the direct negative effect of a carbon tax on chicken consumption is stronger than the indirect (positive) substitution effect from carbon-intensive products to chicken.
I developed a non-linear market model to predict the consumption of different animal products after a tax, based on own-price and cross-price elasticities.
When calibrated for the United States, this model predicts a decrease in the consumption of all animal products considered (beef, chicken, pork, and farmed fish). Therefore, the modelled carbon tax is actually good for animal welfare, assuming that animals live net-negative lives.
A slaughter tax (a tax per slaughtered animal) would be more tax-efficient if the death of an animal is valued at ~10% or more of the Social Cost of Carbon (SCC), assuming that all animal deaths are valued equally. (The SCC is approximately $185, so the threshold is about $18.5.)
Anticipating tax effects is difficult, and this approach has its limitations. The takeaway from this post should not be "carbon taxation is great for ani

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Small Animal Replacement Problem