Most quantitative scenarios used by the #IPCC are based on the #SharedSocioeconomicPathways (or #SSP), implemented in process-based #IntegratedAssessment models - these are not DICE-style models.
Here explained well by #CarbonBrief:
https://www.carbonbrief.org/qa-how-integrated-assessment-models-are-used-to-study-climate-change/
Carbon Brief · Q&A: How 'integrated assessment models' are used to study climate changeWorking out the best ways to tackle climate change is one of the key challenges facing policymakers both today and in the decades ahead. To inform these decisions, scientists and economists have developed a suite of tools known as “Integrated assessment models” (IAMs).