Numerical simulations of contrail-to-cirrus transition – Part 1: An extensive parametric study

摘要: Abstract. Simulations of contrail-to-cirrus transition over up to 6 h were performed using a LES-model. The sensitivity microphysical, optical and geometric contrail properties relative humidity RHi, temperature T vertical wind shear s was investigated in an extensive parametric study. dominant parameter for evolution is humidity. Substantial spreading only visible RHi≳120%. Vertical has smaller effect on than human observers might expect from the visual impression. Our model shows that after few hours water vapour removed by falling ice crystals layer can be several times higher mass actually present at any instance.