Simulation Study of the Applicability of the “Slice” Approach to Assessing the Water Content in Clouds from the Radar Return Signal
Round 1
Reviewer 1 Report
General Comments
This paper is about the possible coherent scattering from clouds, which is an interesting and possibly useful in some cases subject. Actually, it is a validation of Eq. (7) and indirectly Eq. (1) using simulated data with specific distributions of droplet number and water content per slice. The slice volume method to study the coherent scattering is indeed a very promising approach. A non-Poisson distribution of number of droplets per slice (a modified gamma distribution was used) implies correlated small scale fluctuations of this number, which is not certain for droplets with significant inertia like raindrops but possible for cloud droplets. Thus, it should be mentioned in the introduction that this research is mainly applicable to non-precipitating clouds.
Specific Comments
l. 166, Eq. (19): It is not well understood what this equation means. Does this mean to replace x drawn from a gamma distribution with x+(<x>-p) in order to modify its mean value?
l. 250, Table 1: It seems that the χ values given in Table 1with prescribed ξΝ are for a slice volume of 1cm3. Considering that a number of 3000-12000 slices per pulse length was used and a typical radar beam width is 1 deg probably the final radar volume is very small? Thus, the χ value in these simulations may correspond to quite higher values compared e.g. to the estimated value of χ using aircraft data of 4.25 for 100 cm3 (slice) volumes as used in Yurchak 2009?
Fig. 2: These figures should be made more clear.
Fig. 3: It would be useful to the reader to show also the difference from the Poisson (incoherent scattering) case, so that the importance of coherent scattering can be understood.
Author Response
Dear reviewer,
Please read my responses in the attached file.
Thank you!
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The radar cross section of rain is considered using the “slice” approach. Radar receives electric fields (sometimes called voltages) from the slices, not powers. The electric fields should be summed up with phases depending on the positions of slices in a volume of radar wavelength deep. The power (RCS) must be calculated from the sum of the fields, which include the phases. I do not see such a summation in the manuscript. This is my major concern. I think such a summation should be discussed I the manuscript.
Author Response
Dear reviewer,
Please read my responses in the attached file.
Thank you!
Author Response File: Author Response.pdf
Reviewer 3 Report
Dear Author,
Please find attached my comments
Best regards
Comments for author File: Comments.pdf
Author Response
Dear reviewer,
Please read my responses in the attached file.
Thank you!
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The author replied satisfactorily in most of the comments and made the corresponding additions and changes.
Regarding Table 1, the reply that "Values χ in Table 1 are not specified, but obtained as a result of direct calculation based on the simulation results" could be added too in the manuscript. However, according to the definitions of χ and ξN in sections 1 and 2 and Eq. (8): χ=ξN2<Ns>=ξN2<no>V(R)s which gave my estimation of the same value V(R)s=1cm3 (which means 100 droplets per slice volume according to <n0>) for all reported χ in the table. I guess the slice volume (i.e. the slice length Δs<<λ) can be made as small as needed and not only Δs=λ/8 (or λ/50 for Vs=30.6 m3 at 10 km range mentioned in the reply). Thus, I would expect that such a small slice volume could be chosen and simply increase the slice number in the radar volume to get a typical value for it.
Author Response
Dear reviewer,
Please read my response in the attached file.
Thank you!
Author Response File: Author Response.pdf
