The impact pulse and restoration curves: Going beyond mitigation and stabilization

Mitigation measures proposed as a response to the carbon and climate problem represent only the first half of a complete solution. Proactively repairing the damage through restoration represents the remaining half, which must entail the capture and storage of trillions of tons of carbon dioxide (CO2). Given that the time required for natural processes to restore the concentration of atmospheric CO2 to its baseline level is on the order of centuries, timely removal must involve carbon dioxide removal (CDR) geoengineering. Idealized impact and restoration scenarios, which build upon earlier conceptions of stabilization wedges, are proposed as conceptual tools with which to frame policy responses. These scenarios suggest that climate policy must weigh tradeoffs between nearer-term mitigation measures and longer-term CDR interventions. The tradeoffs depend on whether we wish to minimize the magnitude (peak CO2 concentration) or duration (time to reach pre-industrial CO2 levels) of the impact. Generalizing beyond the specific example of climate change, more rigorous consideration of technology-dependent impact and restoration scenarios can help provide a much-needed reality check for both environmental alarmism and technological optimism. This check is important as humanity transitions from the unintentional Anthropocene to the intentional Anthropocene over the course of this century. The prospect of the intentional Anthropocene also raises important ethical questions about the human-nature relationship.