Hello Karl, many thanks for this excellent article. I would be interested to learn more about the mathematical side of the models as well as the modelling techniques used; I probably follow the links given.

The figure of $1.5T presented as an annual cost reminds me of David McKay's "Renewable Energy - Without the hot air", in particular https://www.withouthotair.com/c28/page_220.shtml putting expenditure for climate change mitigation in perspective by comparing with various costs such as the UK bail-out of banks ($1T) or the Iraq war ($2T).