There is growing evidence that anthropogenic carbon dioxide (CO2) emissions as a by-product of the combustion of fossil fuels for energy use is raising the earth's temperatures and potentially leading to irreversible climate change. Additionally the growth in global emissions is likely to rise at an increasing rate due economic growth, especially in developing countries. Leading climate change mitigation strategies require a global CO2 emission permit trading regime which is postulated to facilitate the lowest cost emission reduction options and technologies. However, given the technologies are still maturing the economic considerations appear to dictate slow initial reductions which will then grow at an increasing rate as technologies such as wind, solar and carbon capture and storage mature. These economic considerations however may be in conflict with longer-term optimization of costs and benefits, which may be better addressed by earlier intervention. In this paper we present a Modelica model designed to allow exploration of the tradeoffs between least cost emission cuts and early stabilization of atmospheric carbon dioxide.