This the demonization of Bitcoin's proof-of-work is much less useful than campaigning for a carbon tax To answer the original question, I see no way that one

This the demonization of Bitcoin's proof-of-work is much less useful than campaigning for a carbon tax To answer the original question, I see no way that one could create a "proof-of-decarbonization" consensus system for a cryptosystem. Or at least such a system would be harder to implement than a carbon tax.