Sustained Neutralization of the Warming Response to Emissions through a Portfolio of GHG Mitigation Strategies

Both emissions abatement and carbon dioxide removal will play a critical role in achieving a global net-zero scenario under which temperatures are stabilized. In the near term, organizations pursuing their own net-zero targets may use superpollutant emission abatement and both shorter- and longer-durability carbon dioxide removal to compensate for their remaining emissions. Because these mitigation strategies have climate impacts across distinct timescales, they can serve as powerful and complementary tools to address both the acute near-term and long-term equilibrium warming response to emissions. However, the distinct timescales of these impacts mean that, if accounting approaches are to ensure emissions remain compensated across all time horizons, they must explicitly evaluate the impact of each mitigation strategy as a function of time. We propose one such accounting approach, based on sustained warming neutralization. By translating the climate impacts of both emissions and mitigation into a single metric - the continuous global mean surface temperature response - the approach aims to ensure the neutralization of the warming response to an emission in both the near- and long-term. Ultimately, this warming neutralization approach structurally aligns emission compensation claims with global goals for temperature stabilization. We then introduce a specific method through which an organization can use the approach to design mitigation portfolios to compensate for its emissions. We invite future work to consider how the warming neutralization approach could be operationalized in a way that ensures impactful, accessible, and widely recognized emissions claims.