And others are benefitting from positive externalities of warmer weather, reducing need for heating, increases yields due to increased CO2 concentration etc. Thing is, it’s incredibly hard to put a number on net costs on climate change. The most serious recent attempt to do that had its author, William Nordhaus, a Nobel Prize in Economics. The estimated figure, by the way, is very low compared to the zeal of the activists.

Now, of course, the carbon tax proponents are not really interested in the actual costs. They either ideologically hate emissions, and their desire to institute carbon tax is vindictive in its nature, and all talk about “externalities” is for them just a distraction, or they are politicians who use carbon tax as an excuse to increase their political power and tax revenues. Nobody is motivated by actual economic efficiency, and calling them Pigouvian taxes is a distraction.

William's Nordhaus models for which he has received the Nobel prize predate the millennium, and have been superceded since then by much better models. His models are highly problematic, now that we know that you cannot extrapolate the average temperature on GDP due to increased amplitude, and for many other reasons. That is why the Nobel committee awarded it not for the current relevance of the results, but for the pioneering nature of the research.

[0] https://www.umweltbundesamt.de/sites/default/files/medien/14...

Once you fix energy production, vehicles transport and heating most of those things are gone.

If we looked air air-travel in isolation it would be a lot lower.