Identifying, investigating and mitigating non-CO2 emissions

Burning kerosene creates both carbon dioxide (CO₂) and non-CO₂ emissions. The latter are composed primarily of water vapour, gaseous species such as nitrogen oxides, and various aerosols.  In certain conditions, these non-CO₂ emissions can cause condensation trails, widely known as contrails. Contrails are essentially ice cirrus clouds. Although they both reflect incoming solar radiation and trap outgoing heat, contrails have a net warming effect.

Non-CO₂ emissions can be mitigated using accurate climate impact forecasting models. This allows flights to navigate around, under or above areas favouring contrail formation with air traffic management permission. However alternative trajectories can be longer, increasing both CO₂ emissions and the cost of operating the flight. It is a delicate trade-off.  

Our panelists discussed the current status of non-CO₂ research and how it contributes to more accurate climate impact models. The discussion included results about operational mitigation and the use of different fuel types and aromatics.