Coupled evolution of the economy and the atmosphere

Introduction Conclusions References Tables Figures Back Close Full Screen / Esc This discussion paper is/has been under review for the journal Earth System Dynamics (ESD). Please refer to the corresponding final paper in ESD if available. Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract In a prior study (Garrett, 2011), I introduced a simple thermodynamics-based economic growth model. By treating civilization as a whole, it was found that the global econ-omy's current rate of energy consumption can be tied through a constant to its current accumulation of wealth. The value of the constant is λ = 9.7 ± 0.3 milliwatts per 1990 5 US dollar. Here, this model is coupled to a linear formulation for the evolution of atmospheric CO 2 concentrations. Despite the model's extreme simplicity, multi-decadal hindcasts of trajectories in gross world product (GWP) and CO 2 agree closely with recent observations. Extending the model to the future, the model implies that the well-known IPCC SRES scenarios substantially underestimate how much CO 2 levels 10 will rise for a given level of future economic prosperity. Instead, what is shown is that, like a long-term natural disaster, future greenhouse warming should be expected to retard the real growth of wealth through inflationary pressures. Because wealth is tied to rates of energy consumption through the constant λ, it follows that dangerous climate change should be a negative feedback on CO 2 emission rates, and therefore the ulti-15 mate extent of greenhouse warming. Nonetheless, if atmospheric CO 2 concentrations are to remain below a " dangerous " level of 450 ppmv (Hansen et al., 2007), there will have to be some combination of an unrealistically rapid rate of energy decarboniza-tion and a near immediate collapse of civilization wealth. Effectively, civilization is in a double-bind. If civilization does not collapse quickly this century, then CO 2 levels 20 will likely end up exceeding 1000 ppmv; but, if CO 2 levels rise by this much, then the danger is that civilization will gradually tend towards collapse.