Dear Fifi,

First, apologies for the delay in responding. I have now considered the referees' comments and your responses to address them. I am very pleased to say that I think the manuscript will now be suitable for publication in The Cryosphere after some minor changes to grammar and phrasing that I have listed below. Congratulations on this work. This is a very interesting and illuminating investigation of the near surface properties of the Antarctic Ice Sheet.

Yours sincerely,

Robert Arthern

Change “Spaceborne radar altimeters is a valuable tool” to “Spaceborne radar altimeters are a valuable tool”

Change “To explain this contrasted behaviour” to “To explain this contrasting behavior”

Change “At Ku band, the seasonal cycle is in the Region 1 dominated by the volume echo and by the surface echo in the other one.” to “At Ku band, the seasonal cycle is dominated by the volume echo in Region 1 and by the surface echo in Region 2”.

Change “more accurate correction” to “more accurate corrections”.

Change “laser altimeter beam that not penetrates” to “laser altimeter beam that does not penetrate”

Re. “Zwally et al. (2005) used an empirical linear relationship between the surface elevation residuals and the backscattering coefficient residuals at a crossover points of the satellite tracks (data points where satellite tracks cross)” Note that Wingham et al. (1998) describe a similar correction.

Line 115. Change “This model account for the surface and the volume echoes.” to “This model accounts for the surface and the volume echoes.”

Change “a randomly rough surfaces” to “a randomly rough surface”

Change “snow the density” to “the snow density”

Properly subscript “Am and Tm”

Change “assumed equals to an average” to “assumed equal to an average”

Line 310 Change “allowed to carry out this spatial and temporal comparatives analysis” to “carries out spatial and temporal comparative analysis”

Change “dependence to radar frequency” to “dependence on radar frequency”

Change “build robust correction” to “build a robust correction”

Please also make sure to double check in the final proofs that the modified title is used (Antarctic Ice Sheet rather than Antarctica Ice Sheet)