The authors present a relatively comprehensive snow drift model, taking into consideration of vertical diffusion of humidity.The results are compared with published data.It is shown that the results are at least qualitatively consistent with the observations and in some aspect also quantitatively consistent.I see considerable value in the further development of the model to a full scale comprehensive model.This model is a very good starting point, as it already has all the ingredients.The text can be improved.The introduction can be shorter.The very first sentence in the abstract is a very long sentence trying to say too much.Also, the model formulation can be made more concise, e.g., Equation (1).It is unnecessary to write it in such a