Short answers, pulled from the story.
Integrated assessment modelling combines society, economy and the climate system into one single framework. Scientists use these tools to accommodate informed policy-making within the context of climate change.
Cost-benefit integrated assessment models such as DICE, PAGE, and FUND serve as main tools for calculating the social cost of carbon. The US Interagency Working Group uses these figures for regulatory impact analysis.
Scientists at the Potsdam Institute for Climate Impact Research released a dataset in 2022 showing annual greenhouse gas emissions across various NGFS climate scenarios. This data comes from the REMIND-MAgPIE model which links economic processes with atmospheric changes.
Critics point out reliance on economic models inappropriate to the specific problem at hand leading to overestimated cost-benefit ratios. Nicholas Stern argued in an October 2021 working paper that existing IAMs cannot capture economic realities under rapid progress.
Non-equilibrium models take a different approach by using econometric equations or evolutionary economics concepts instead of assuming rational agents. Examples include the E3ME model based on econometrics and the agent-based DSK-model which simulate shared socioeconomic pathways.