Incident velocity and incident angle are important parameters for Martian aeolian research. In this paper we have established a model for investigating the saltation of sand in steady state, mainly considering the hopping of sand in the air and sand-bed collision process. The model proves to be able to predict sand motion in steady-state saltation on Earth well both qualitatively and quantitatively. Thus, it was applied to the study of sand saltation on Mars. With the help of the model, we found incident velocities and incident angles of Martian grains in steady-state saltation in cases of various wind strengths. Then, these predicted velocities and angles were compared with previous studies. Besides, the model also can show information on lift-off parameters of saltating particles. Therefore, it allows us to study other features in aeolian processes such as the saltation length and sand transport rate.

The studies on wind‐blown sand are crucial for understanding the change of climate and landscape on Mars. However, the disadvantages of the saltation models may result in unreliable predictions. In this paper, the saltation model has been improved from two main aspects, the aerodynamic surface roughness and the lift‐off parameters. The aerodynamic surface roughness is expressed as function of particle size, wind strength, air density, and air dynamic viscosity. The lift‐off parameters are improved through including the dependence of restitution coefficient on incident parameters and the correlation between saltating speed and angle. The improved model proved to be capable of reproducing the observed data well in both stable stage and evolution process. The modeling of wind‐blown sand is promoted by all improved aspects, and the dependence of restitution coefficient on incident parameters could not be ignored. The constant restitution coefficient and uncorrelated lift‐off parameter distributions would lead to both the overestimation of the sand transport rate and apparent surface roughness and the delay of evolution process. The distribution of lift‐off speed and the evolution of lift‐off parameters on Mars are found to be different from those on Earth. This may thus suggest that it is inappropriate to predict the evolution of wind‐blown sand by using the lift‐off velocity obtained in steady state saltation. And it also may be problematic to predict the wind‐blown sand on Mars through applying the lift‐off velocity obtained upon terrestrial conditions directly.

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