AIRIC - Aviation Impacts on climate via aerosol-Radiation and Interactions with Clouds

AIRIC represents a timely effort to close a critical knowledge gap in aviation climate science. The project will use state-of-the-art climate modelling to deliver robust, actionable insights that support the transition to a more sustainable aviation sector.

Despite substantial recent improvements in aviation climate impacts research, the specific role of aerosols emitted by aircraft, particularly their interactions with radiation and clouds, remains poorly constrained. This uncertainty significantly hampers our ability to quantify aviation’s total climate impact and to design effective mitigation strategies. Aircraft-emitted aerosols have been identified as potentially major contributors to aviation-induced radiative forcing, primarily through complex aerosol-radiation interactions (ARI) and aerosol-cloud interactions (ACI). However, the magnitude and mechanisms of these effects are not well understood, largely due to limitations in current observational data and modelling capabilities.

This knowledge gap is especially concerning in light of the ambitious climate targets set for the aviation sector, including commitments to achieve net-zero CO₂ emissions. Achieving these goals requires a step-change in our scientific understanding of aviation-induced aerosol effects and the development of advanced modelling tools to inform policy and technological innovation.

AIRIC will address these challenges by focusing on how the two key processes, ARI and ACI, relate to aviation aerosols. Building on our team’s extensive expertise in aerosol, cloud, and aviation climate modelling, the project will advance the capabilities of the UK Met Office unified model (UM) to more accurately represent the chemistry, microphysics, and radiative properties of aviation aerosols. This will involve the integration of improved parameterisations and the application of observational constraints to better simulate the interactions between aviation aerosols, radiation, and clouds.

Impact

AIRIC will substantially reduce the largest source of uncertainty in aviation climate impact assessments. The project’s outcomes will directly inform the development of future aviation technologies and climate policies.

The findings will be highly relevant to policymakers and industry stakeholders, providing a robust scientific basis for investment decisions and regulatory frameworks aimed at reducing aviation’s climate impact.