Abstract. Different treatments of the Kelvin effect in LES modeling of early contrails are shown to cause variations in the survival rate of ice particles by up to a factor of 4 and in optical depth and mean particle size by up to 50 %. The Kelvin effect which varies exponentially with particle size, can reduce or even suppress the impact of other important ambient parameters, such as ice supersaturation, on particle survival rate. Lowering or neglecting the Kelvin effect is shown to substantially alter the evolution of the ice particle size distribution and delay the onset of particle loss. A strongly Kelvin effect dependent exponential relation between particle survival rate and particle size is shown for high EI_soot (O(10¹⁵)).