Social Cost of Greenhouse Gases -- OPTiMEM and the Heat Conjecture(s)
This study addresses the disconnect between climate science and economics by proposing a physically grounded framework for estimating the social cost of greenhouse gases (SCGHG). To this end, the authors develop OPTiMEM, a coupled physical–macroeconomic model that, for the first time, integrates an ocean heat content (OHC) physics module with macroeconomic analysis. The model simulates fossil fuel emissions, atmospheric CO₂ concentrations, surface warming, and oceanic heat uptake through a carbon-consumption-driven climate component, constrained by state-of-the-art radiative forcing equations and an energy production model. OPTiMEM successfully reproduces historical records of emissions, temperature, and OHC, offering a verifiable and physically consistent SCGHG assessment framework. This approach overcomes key limitations of conventional purely economic models and provides a robust scientific foundation for climate policy design.