Since any UBI schedule can be adjusted to be more or less progressive, you simply sum the impact of carbon tax + UBI as a package and tweak until you get the de

Since any UBI schedule can be adjusted to be more or less progressive, you simply sum the impact of carbon tax + UBI as a package and tweak until you get the desired net result. By the way, this is already a very standard analysis that economists do, and the Congressional Budget Office (CBO) is well-funded, non-partisan, and is probably the best institution in the world for doing this sort of work. Obamacare, the Trump tax cuts, tweaks to Social Security, all these proposals get evaluated over a long time frame by the CBO and the results are public (for example https://www.cbo.gov/publication/45447 https://www.cbo.gov/publication/45447).