Atmospheric Methane Removal as a Third Climate Intervention: Termination Risks and Air Pollutant Effects

TL;DR

Atmospheric Methane Removal (AMR) offers a potential climate intervention, but its effects are temporary and influenced by air pollution levels, with unique termination risks compared to other methods.

Contribution

This paper highlights the transient nature of AMR's warming mitigation and its interaction with air quality, providing a comparative analysis with other climate interventions.

Findings

AMR's avoided warming is not durable due to methane's short lifetime.

Termination of AMR leads to a temperature rebound less abrupt than SRM.

AMR's impact on surface ozone varies with background pollution levels.

Abstract

Atmospheric Methane Removal (AMR) is a third class of climate intervention, along with Carbon Dioxide Removal (CDR) and Solar Radiation Management (SRM). We show that, unlike CDR, the avoided warming by AMR is not durable due to methane's short atmospheric lifetime, although its temperature rebound upon termination is less abrupt than that of SRM. AMR's impact on air quality (surface ozone) can be further modulated by background pollutant levels.