A) We've already passed the expected point of no return for 0.5 (warned about as early as the 1960s as I recall) and 1.0. As of 2023 we have already experienced

A) We've already passed the expected point of no return for 0.5 (warned about as early as the 1960s as I recall) and 1.0. As of 2023 we have already experienced years at as much as 1.2 degrees (above pre-industrial average). B) The 1.5 degree budget, as I recall is the "best wish" case of the 2015 Paris agreement. C) The 2 degree budget is the "worst case" allowable by the 2015 Paris agreement. D) The Paris agreement was based on previous IPCC reports on some of the expected outcomes at 1.5 degree and 2 degree budgets. The Paris agreement was largely trying to pick the smallest number that still seemed feasible in 2015.