Contrail radiative dependence on ice particle number concentration

Abstract Recent studies on low aromatic fuels have shown that lower soot number emissions may reduce contrail ice particle concentrations (Nice). Here we implemented, in a sophisticated radiative transfer model, two size distribution (PSD) schemes order to estimate the forcing’s (RF) dependence these prospective Nice reductions resulting from introduction of sustainable aviation fuels. The results show an 85% reduction produces 35% smaller RF, while neglecting all non-radiative effects. This RF only considers effects change assumed here, and neglects other potentially important microphysical mechanisms relationship between Nice. A comparison our with previous published estimates full climate model simulations, shows similar those which also take into account mechanisms, evidencing need for more allocate contribution changes, as this would guide possible mitigation implementations. Despite modeled being largely independent IWC, it is through simultaneous improvement IWC representation models can be better constrained. because calculated varied by factor 3 when assuming ±30% range; 5 if a, still conservative, ±60% range was prescribed, suggesting differences prescribed values different explain large discrepancies amongst estimates. higher values, IWCs found contrails even after several hours, compared surrounding cirrus under atmospheric conditions, were assessed conclude mainly make young linear year 2006 65%.