In a recent article (open access) in Environmental Research Letters, N.P. Myhrvold & Ken Caldeira lay out the case for why a transition to low-carbon electrical sources is likely to prove a long haul due to the inertia of the climatic system.
Among the take-aways from the article:
- The larger contribution (relative to during operation) of greenhouse gas emissions during construction of nuclear and renewable power plants (vs. fossil fuel power plants) results in a sawtooth trend in atmospheric greenhouse gas concentrations for a constant output of electricity;
- Because of the long residence time of atmospheric carbon dioxide and ocean thermal inertia, idealized energy conservation takes 20 years to achieve a 25% reduction in warming associated with high greenhouse gas-emitting sources, and 40 years to achieve a 50 year reduction;
- A transition to natural gas would by no means be a panacea to climatic issues in the short term, requiring more than a century or longer to reduce warming associated with high greenhouse gas emitting sources by 25%;
- Replacement of conventional coal-fired power plants with coal plants fitted with carbon capture and sequestration technology (CCS) would only reduce warming associated with high greenhouse gas emitting sources by7 25% after 26-110 years, or a 50% reduction in 52 years under optimistic assumptions, or several centuries under more pessimistic assumptions:
- While a transition to low carbon sources doesn’t substantially bend the warming curve in the short or medium term, a failure to do so could threaten even more serious environmental impacts in the second half of this century and beyond.
Among the class discussion questions that this article might invite are the following:
- What are the implications of the study for prioritization of resources for adaptation initiatives?;
- Do the results of this study provide any additional impetus for climate geoengineering interventions?;
- Does the study suggest that we should not be aggressively pursuing a transition to natural gas and/or a commitment to CCS?